Journal articles: 'Porphyrin'

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Stölzel, Ulrich, Thomas Stauch, and Ilja Kubisch. "Porphyrien." Der Internist 62, no. 9 (June 29, 2021): 937–51. http://dx.doi.org/10.1007/s00108-021-01066-1.

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ZusammenfassungPorphyrien werden durch Enzymdefekte der Hämbiosynthese hervorgerufen und anhand spezifischer biochemischer Muster von Porphyrinen und deren Vorläufern in Urin, Stuhl und Blut diagnostiziert. Das jeweilige Muster der akkumulierten Porphyrine, Vorläufer und Derivate ist verbunden mit der klinischen Ausprägung, die abdominale, neurologische, psychiatrische, endokrine, kardiovaskuläre Symptome, Leberschaden und/oder Lichtempfindlichkeit der Haut umfassen kann. Klinisch werden akute und nichtakute Porphyrien unterschieden. Bei symptomatischen (klinisch aktiven), akuten hepatischen Porphyrien – hierzu gehören akute intermittierende Porphyrie, Porphyria variegata, hereditäre Koproporphyrie und Doss-Porphyrie – kommt es aufgrund einer Regulationsstörung zur Kumulation der Porphyrinvorläufer 5‑Aminolävulinsäure und Porphobilinogen. Bei den nichtakuten Formen – u. a. Porphyria cutanea tarda, erythropoetische und X‑chromosomale Protoporphyrie sowie kongenitale erythropoetische Porphyrie – führen akkumulierte Porphyrine zu Lichtempfindlichkeit (Fotodermatose) und mitunter auch zu schweren Leberschäden. Zur Therapie der Porphyrien stehen sowohl bewährte und sichere als auch innovative Optionen zur Verfügung.

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Hindmarsh, J. Thomas, Linda Oliveras, and Donald C. Greenway. "Plasma Porphyrins in the Porphyrias." Clinical Chemistry 45, no. 7 (July 1, 1999): 1070–76. http://dx.doi.org/10.1093/clinchem/45.7.1070.

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Abstract Background: As an aid in the diagnosis and management of porphyria we have developed a method to fractionate and quantify plasma porphyrins and have evaluated its use in various porphyrias. Methods: We used HPLC with fluorometric detection to measure plasma concentrations of uroporphyrin I and III, heptacarboxyl III, hexacarboxyl III, pentacarboxyl III, and coproporphyrin I and III. We studied 245 healthy subjects, 32 patients with classical porphyria cutanea tarda (PCT), 12 patients with PCT of renal failure, 13 patients with renal failure, 8 patients with pseudoporphyria of renal failure, 3 patients with acute intermittent porphyria, 5 patients with variegate porphyria, 5 patients with hereditary coproporphyria, and 4 patients with erythropoietic protoporphyria. Results: Between-run CVs were 5.4–13%. The recoveries of porphyrins added to plasma were 71–114% except for protoporphyrin, which could not be reliably measured with this technique. Plasma porphyrin patterns clearly identified PCT, and its clinical sensitivity equaled that of urine porphyrin fractionation. The patterns also allowed differentiation of PCT of renal failure from pseudoporphyria of renal failure. Conclusions: The assay of plasma porphyrins identifies patients with PCT and appears particularly useful for differentiating PCT of renal failure from pseudoporphyria of renal failure.

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Woolf, Jacqueline, Joanne T. Marsden, Timothy Degg, Sharon Whatley, Paul Reed, Nadia Brazil, M. Felicity Stewart, and Michael Badminton. "Best practice guidelines on first-line laboratory testing for porphyria." Annals of Clinical Biochemistry: International Journal of Laboratory Medicine 54, no. 2 (January 19, 2017): 188–98. http://dx.doi.org/10.1177/0004563216667965.

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The porphyrias are disorders of haem biosynthesis which present with acute neurovisceral attacks or disorders of sun-exposed skin. Acute attacks occur mainly in adults and comprise severe abdominal pain, nausea, vomiting, autonomic disturbance, central nervous system involvement and peripheral motor neuropathy. Cutaneous porphyrias can be acute or chronic presenting at various ages. Timely diagnosis depends on clinical suspicion leading to referral of appropriate samples for screening by reliable biochemical methods. All samples should be protected from light. Investigation for an acute attack: • Porphobilinogen (PBG) quantitation in a random urine sample collected during symptoms. Urine concentration must be assessed by measuring creatinine, and a repeat requested if urine creatinine <2 mmol/L. • Urgent porphobilinogen testing should be available within 24 h of sample receipt at the local laboratory. Urine porphyrin excretion (TUP) should subsequently be measured on this urine. • Urine porphobilinogen should be measured using a validated quantitative ion-exchange resin-based method or LC-MS. • Increased urine porphobilinogen excretion requires confirmatory testing and clinical advice from the National Acute Porphyria Service. • Identification of individual acute porphyrias requires analysis of urine, plasma and faecal porphyrins. Investigation for cutaneous porphyria: • An EDTA blood sample for plasma porphyrin fluorescence emission spectroscopy and random urine sample for TUP. • Whole blood for porphyrin analysis is essential to identify protoporphyria. • Faeces need only be collected, if first-line tests are positive or if clinical symptoms persist. Investigation for latent porphyria or family history: • Contact a specialist porphyria laboratory for advice. Clinical, family details are usually required.

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Puzikova, А. I., Е. А. Litvin, D. А. Kildyushkin, and А. Е. Druy. "Application of high-performance liquid chromatography in porphyrias diagnostics." Pediatric Hematology/Oncology and Immunopathology 20, no. 3 (October 8, 2021): 140–44. http://dx.doi.org/10.24287/1726-1708-2021-20-3-140-144.

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Porphyrias are distinguished by the stage of heme synthesis at which a failure occurs, leading to the accumulation of intermediate products – porphyrins. Due to the low specificity of clinical manifestations of porphyria and the latent course of the disease, their timely diagnosis is difficult. This article substantiates the effectiveness of high-performance liquid chromatography method in the determination of porphyrins. The method is suitable for porphyrin determination in urine, blood and feces of patients. Examples of its work are shown.

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Krivosheev, Alexander B., L. Ya Kupriyanova, and M. A. Kondratova. "DOUBLE PORPHYRIA: LITERATURE REVIEW AND ANALYSIS OF CLINICAL OBSERVATION." Russian Journal of Skin and Venereal Diseases 21, no. 2 (April 15, 2018): 120–24. http://dx.doi.org/10.18821/1560-9588-2018-21-2-120-124.

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A brief review of the literature on the problem of double porphyria and analysis of its own observation is presented. For more than 10 years patient B was observed for more than 10 years with a verified diagnosis of acute intermittent porphyria, which manifested with acute pain abdominal syndrome, neurological disorders in the form of peripheral polyneuropathy and hemiparesis of lower extremities, and hypertension syndrome was also noted. The observed clinical symptoms corresponded to an acute porphyrin crisis in the manifestation and / or relapse of acute intermittent porphyria. The diagnosis was confirmed by a quantitative determination of the excretory profile of porphyrin precursors (δ-aminocaproic acid, porphobilinogen) and porphyrin fractions (uroporphyrin, coproporphyrin). Their concentrations are significantly (especially porphyrin precursors) exceeding the control values, which is the cardinal diagnostic criterion of acute intermittent porphyria. Against the backdrop of persistent clinical and biochemical remission of acute intermittent porphyria, symptoms of photosensitization of the skin (blisters, erosion, pigment spots) on the dorsal surface of the hands began to appear in 4 years. Later, hypertrichosis was formed in the temporo-periorbital region. The constellation type of the excretory profile of porphyrins began to change. Against the backdrop of persistent increased excretion of porphyrin precursors (δ-aminolevulinic acid and porphobilinogen), a progressive increase in the excretion of the fraction of uroporphyrin was observed, which became dominant (up to 58% of the total content of porphyrins). Such a prolonged observation in the dynamics allowed us to state the appearance of a new variant of the porphyrin exchange disturbance, which, taking into account clinical symptoms, corresponded to another form of hepatic porphyria, namely, late cutaneous porphyria. The clinical and biochemical changes in the excretory profile of the parameters of porphyrin metabolism registered in the dynamics of observation may indicate the occurrence of a combined enzymatic defect characteristic of double porphyria. In our case, a manifestation of late cutaneous porphyria was noted against a background of compensated acute intermittent porphyria.

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Carson, R. W., E. J. Dunnigan, T. D. DuBose, D. E. Goeger, and K. E. Anderson. "Removal of plasma porphyrins with high-flux hemodialysis in porphyria cutanea tarda associated with end-stage renal disease." Journal of the American Society of Nephrology 2, no. 9 (March 1992): 1445–50. http://dx.doi.org/10.1681/asn.v291445.

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Plasma porphyrin levels are markedly increased in patients with porphyria cutanea tarda (PCT) associated with end-stage renal disease. Conventional hemodialysis (CHD) with lower blood flow rates (less than 250 mL/min) and cuprophan or cellulose acetate membranes is ineffective in removing significant amounts of porphyrins in this condition. Changes in plasma porphyrin levels and porphyrin clearances during hemodialysis with higher blood flow rates and more-permeable, high-efficiency cellulose acetate and high-flux polysulfone dialyzers were evaluated in a chronic hemodialysis patient with PCT and markedly elevated plasma porphyrins. The polysulfone membrane achieved significantly better fractional porphyrin removal (P = 0.02) and porphyrin clearances (P less than 0.01) than did the high-efficiency cellulose acetate membrane. After conversion from maintenance CHD with a standard cellulose acetate dialyzer to a 4-wk period of high-flux hemodialysis (HFHD) with a polysulfone dialyzer, predialysis plasma porphyrins fell by 37%. After returning to CHD, plasma porphyrins returned to the higher prestudy levels. These observations suggest that HFHD with more permeable membranes and higher blood flow rates removes porphyrins more effectively than does CHD. HFHD may be a useful adjunct to other measures used in treating dialysis patients with PCT.

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Egemen, Gamze, Mustafa Hayvalı, Zeynel Kılıç, A. Osman Solak, and Zafer Üstündağ. "Phosphorus-nitrogen compounds Part 17: The synthesis, spectral and electrochemical investigations of porphyrino-phosphazenes." Journal of Porphyrins and Phthalocyanines 14, no. 03 (March 2010): 227–34. http://dx.doi.org/10.1142/s1088424610001945.

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The reactions of unsymmetrical porphyrins (1 and 2) with Ni(OAc)2·4H2O in boiling DMF produce porphyrin complexes (3 and 4). From the reactions of free porphyrin ligands 1 and 2 with hexachlorocyclotriphosphazatriene, N3P3Cl6 , the new free porphyrino-phosphazene derivatives (5 and 6) are obtained. On the other hand, the reactions of N3P3Cl6 with porphyrin complexes (3 and 4) afford the new porphyrino-phosphazene complexes (7 and 8). In the literature there are a few examples of the porphyrino-phosphazene architectures. The structural investigations of all the compounds have been made by elemental analyses, MS, FTIR, 1H NMR, 31P NMR and UV-visible techniques. The cyclic voltammograms (CVs) are examined in acetonitrile (MeCN) containing 0.1 M tetrabutylammonium-tetrafluoroborate (TBATFB) to investigate the surface attachment properties at the glassy carbon electrode (GCE) and the influence of the presence of metal cations in the porphyrin ring.

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Hindmarsh, J. T. "The porphyrias: recent advances." Clinical Chemistry 32, no. 7 (July 1, 1986): 1255–63. http://dx.doi.org/10.1093/clinchem/32.7.1255.

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Abstract Recent research has elucidated several of the hitherto poorly understood steps in heme synthesis. This review describes this metabolic pathway and pinpoints the enzymatic blockages in the various porphyrias. Recent advances in the understanding of the etiology of porphyria cutanea tarda are discussed, as are the abnormalities of porphyrin metabolism seen in chronic renal failure and in lead poisoning. An outline is given of the clinical and biochemical abnormalities seen in the porphyrias. Included is an algorithm to aid in the differential diagnosis of these diseases, and a brief review of the new analytical techniques available for the identification and quantification of porphyrins and their precursors in body fluids.

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Lockwood, W. H., V. Poulos, E. Rossi, and D. H. Curnow. "Rapid procedure for fecal porphyrin assay." Clinical Chemistry 31, no. 7 (July 1, 1985): 1163–67. http://dx.doi.org/10.1093/clinchem/31.7.1163.

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Abstract Hydrochloric acid extraction of feces in the presence of ether yields an extract suitable for spectrophotometric estimation of total porphyrin and for further separation by "high-performance" liquid chromatography (HPLC) or thin-layer chromatography. A total porphyrin reference interval of less than 200 nmol/g dry weight of feces was established from data on 106 normal subjects on an unrestricted diet. Total fecal porphyrin values in 11 porphyria cutanea tarda patients were considerably higher than given by the widely used Rimington method (respective means, 652 and 239 nmol/g dry weight). Our HPLC method for separation of porphyrin methyl esters on a silica column, with quantification by fluorescence, is described. HPLC separations performed on 23 porphyria cutanea tarda patients gave the following mean proportions of total fecal porphyrins: dicarboxylics 21%, coproporphyrin 9%, isocoproporphyrins 28%, pentacarboxylporphyrin 9%, hexacarboxylporphyrin 11%, heptacarboxylporphyrin 18%, and uroporphyrin 4%.

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Perkins, S. L., and P. M. Johnson. "Loss of porphyrins from solution during analysis: effect of sample pH and matrix on porphyrin quantification in urine by "high-performance" liquid chromatography." Clinical Chemistry 35, no. 7 (July 1, 1989): 1508–12. http://dx.doi.org/10.1093/clinchem/35.7.1508.

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Abstract We report the effect of sample matrix and pH on quantification of porphyrins by HPLC with fluorimetric detection. For aqueous solutions of pH less than 2.5, HPLC peak heights of the porphyrins increased with decreasing pH, reaching a plateau at pH less than 1.0. This loss of porphyrins from solutions with pH greater than 1.0 appeared to be due to a combination of microprecipitation and aggregation effects. No such "pH effect" was observed for urine samples supplemented with mixed-porphyrin standards. Addition of trace amounts of albumin to aqueous solutions also decreased these pH-related losses. These findings suggest a porphyrin-protein interaction that prevents microprecipitation and aggregation processes. We conclude that standard solutions of porphyrins for HPLC analysis should be prepared in a urine matrix. If aqueous solutions are used, then the pH must be adjusted to less than 1.0. Urine samples from normal individuals require only adjustment of pH to less than 2 before analysis; however, porphyric urines requiring dilution should be prepared with porphyrin-free urine diluent.

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Ricci, Andrea, Claudio Carmine Guida, Paola Manzini, Chiara Cuoghi, and Paolo Ventura. "Kidney Involvement in Acute Hepatic Porphyrias: Pathophysiology and Diagnostic Implications." Diagnostics 11, no. 12 (December 10, 2021): 2324. http://dx.doi.org/10.3390/diagnostics11122324.

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Porphyrias are a group of rare disorders originating from an enzyme dysfunction in the pathway of heme biosynthesis. Depending on the specific enzyme involved, porphyrias manifest under drastically different clinical pictures. The most dramatic presentation of the four congenital acute hepatic porphyrias (AHPs: acute intermittent porphyria—AIP, ALAD deficiency, hereditary coproporphyria—HCP, and porphyria variegata—VP) consists of potentially life-threatening neurovisceral attacks, for which givosiran, a novel and effective siRNA-based therapeutic, has recently been licensed. Nonetheless, the clinical manifestations of acute porphyrias are multifaceted and do not limit themselves to acute attacks. In particular, porphyria-associated kidney disease (PAKD) is a distinct, long-term degenerating condition with specific pathological and clinical features, for which a satisfactory treatment is not available yet. In PAKD, chronic tubule-interstitial damage has been most commonly reported, though other pathologic features (e.g., chronic fibrous intimal hyperplasia) are consistent findings. Given the relevant role of the kidney in porphyrin metabolism, the mechanisms possibly intervening in causing renal damage in AHPs are different: among others, δ-aminolevulinic acid (ALA)-induced oxidative damage on mitochondria, intracellular toxic aggregation of porphyrins in proximal tubular cells, and derangements in the delicate microcirculatory balances of the kidney might be implicated. The presence of a variant of the human peptide transporter 2 (PEPT2), with a greater affinity to its substrates (including ALA), might confer a greater susceptibility to kidney damage in patients with AHPs. Furthermore, a possible effect of givosiran in worsening kidney function has been observed. In sum, the diagnostic workup of AHPs should always include a baseline evaluation of renal function, and periodic monitoring of the progression of kidney disease in patients with AHPs is strongly recommended. This review outlines the role of the kidney in porphyrin metabolism, the available evidence in support of the current etiologic and pathogenetic hypotheses, and the known clinical features of renal involvement in acute hepatic porphyrias.

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Richeter, Sébastien, Christophe Jeandon, Christian Sauber, Jean-Paul Gisselbrecht, Romain Ruppert, and Henry J. Callot. "Preparation, mass spectrometry and electrochemical studies of metal connected porphyrin oligomers." Journal of Porphyrins and Phthalocyanines 06, no. 06 (June 2002): 423–30. http://dx.doi.org/10.1142/s108842460200052x.

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Oligomers built from metal ions and porphyrins bearing enaminoketones at the ring periphery were prepared. These dimers or trimers, where all porphyrinic rings are coplanar, show large interactions in the ground state between the individual porphyrin cores, as shown by their optical properties and electrochemical studies. In particular, a spectacular decrease of the HOMO-LUMO gap (with values as low as 1.32 eV) was observed for monomeric porphyrins metalated on the external sites. Along with standard analytical methods, APPI (Atmospheric Pressure PhotoIonization) mass spectrometry was found to be a very powerful tool to characterize these metal connected porphyrin oligomers.

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Zuijderhoudt, F. M. J., and J. Dorresteijn-de Bok. "Comparison of the Bio-Rad Porphyrin Column Test with a Simple Spectrophotometric Test for Total Urine Porphyrin Concentration." Annals of Clinical Biochemistry: International Journal of Laboratory Medicine 35, no. 3 (May 1998): 418–21. http://dx.doi.org/10.1177/000456329803500312.

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We compared two screening methods for increased urine porphyrin concentration and compared the results with a high-performance liquid chromatography (HPLC) method. The screening methods were the Bio-Rad (Porphyrin) Column Test and a simple spectrophotometric method. Results were obtained for urines with three different porphyrin patterns. Both screening methods were easy to perform. The accuracy and precision of the spectrophotometric method were both slightly better than that of the Bio-Rad Column Test. Recovery measurements in samples with different porphyrin patterns varied between 73% and 59% ( n = 12) for the spectrophotometric method and between 82% and 116% ( n = 12) for the Bio-Rad Column Test as compared to HPLC. Between batch precision measurements revealed coefficients of variation for spectrophotometric and Bio-Rad methods for 2%–4% and 4%–10%, respectively. The recovery of the porphyrins illustrates the Bio-Rad Column Test to be more susceptible to variation in urine porphyrin composition. Both methods will show satisfactory results in cases of overt porphyria because of the high urine porphyrin concentration.

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Ruggian, J. C., S. Fishbane, F. J. Demento, J. K. Maesaka, and G. L. Frei. "Porphyria cutanea tarda in a patient on chronic ambulatory peritoneal dialysis." Journal of the American Society of Nephrology 7, no. 3 (March 1996): 397–402. http://dx.doi.org/10.1681/asn.v73397.

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Porphyria cutanea tarda is a disorder of heme biosynthesis resulting from a defect or deficiency in the enzyme uroporphyrinogen decarboxylase. Heme precursors accumulate in the blood, urine, stool, and skin, where exposure to sunlight results in the clinical manifestations. Porphyria cutanea tarda has been described in adult hemodialysis patients. The pathogenesis of porphyria cutanea tarda in this population is thought to be related to the inability of hemodialysis to adequately clear porphyrin precursors, resulting in increased precursor serum levels, precursor skin deposition, and subsequent clinical manifestations. A proper diagnosis of porphyria cutanea tarda in hemodialysis patients requires fractionation of serum porphyrins. Normalization of the porphyrin profile and reversal of the dermal manifestations require the withdrawal of hepatotoxic agents and the reversal of hepatic iron overload. A case of porphyria cutanea tarda in an adult ESRD patient treated with continuous ambulatory peritoneal dialysis is described. In this patient, the disease was related to elevated serum levels of phenytoin, which had been administered for seizure disorder.

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Schoenfeld, N., and R. Mamet. "Interference of ofloxacin with determination of urinary porphyrins." Clinical Chemistry 40, no. 3 (March 1, 1994): 417–19. http://dx.doi.org/10.1093/clinchem/40.3.417.

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Abstract The second-generation quinolone ofloxacin interferes with the screening test of porphyrins. We observed a 20-fold increase in the porphyrin concentration measured in urine of an ofloxacin-treated patient, compared with drug-free normal urine. Two other fluorinated 4-quinolones tested, norfloxacin and ciprofloxacin, had a less marked effect (a twofold increase), whereas the first-generation quinolone, nalidixic acid, did not affect the measured porphyrin concentration at all. The interference is probably due to the overlap in the emission fluorescence spectra of ofloxacin and urinary porphyrins at approximately 600 nm. To avoid a false-positive diagnosis of porphyria, we suggest using HPLC to separate ofloxacin (10-min retention time) from urinary porphyrins (which only start to elute at 12 min). Nonetheless, given a threefold increase in urinary porphyrins observed in the urine of an ofloxacin-treated patient, we also discuss a possible interference of the drug with the metabolism of porphyrins.

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Sánchez-Muñoz, Esteban, José L. Gárate-Morales, Jacinto Sandoval-Lira, Julio M. Hernández-Pérez, and Rocío Aguilar-Sánchez. "Porphyrin Supramolecular Arrays Formed by Weakly Interacting Meso-Functional Groups on Au(111)." Molecules 24, no. 18 (September 12, 2019): 3326. http://dx.doi.org/10.3390/molecules24183326.

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The formation of a binary porphyrinic self-assembled system between meso-tetrakis(4-carboxyphenyl) porphyrin (TCPP) and meso-tetrakis(4-dimethyl amino) porphyrin (TDAP) was easily designed through non-covalent interactions in solution and adsorbed on a gold substrate. It was found that non-covalent interactions and geometrical conformations between porphyrins allow their self-assembly into a well-defined arrangement, which was confirmed by UV-Vis spectroscopy, electrochemistry, atomic force microscopy and density functional theory (DFT) studies.

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Beukeveld, G. J., B. G. Wolthers, J. J. van Saene, T. H. de Haan, L. W. de Ruyter-Buitenhuis, and R. H. van Saene. "Patterns of porphyrin excretion in feces as determined by liquid chromatography; reference values and the effect of flora suppression." Clinical Chemistry 33, no. 12 (December 1, 1987): 2164–70. http://dx.doi.org/10.1093/clinchem/33.12.2164.

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Abstract While determining reference values for porphyrins in feces as measured by liquid chromatography, we observed strong fluctuations in fecal porphyrin contents. To explain these fluctuations, we selectively suppressed the intestinal flora of healthy persons. Suppression of aerobic flora had no effect on fecal porphyrin excretions, whereas suppression of anaerobic flora completely inhibited the transformation of protoporphyrin to pempto- and deuteroporphyrin for as long as five days after stopping medication. During this latter, the conversion to mesoporphyrin was clearly increased in one person and in others partly affected or decreased. During complete suppression of flora for prolonged periods, the production of proto- and coproporphyrins was decreased and deutero-, pempto-, and mesoporphyrins were absent. We conclude that the nature of fecal porphyrins is mostly affected by action of anaerobic bacteria, different kinds of bacteria having different effects. Some, like aerobic Gram-negative bacteria, have little or no effect on porphyrins; some cause production of mesoporphyrin; some promote a conversion to pempto- and deuteroporphyrin; and some mainly cause production of copro- and protoporphyrin. We give examples in which normal to slightly increased excretions of fecal porphyrin do not exclude a diagnosis of porphyria, and relatively high concentrations do not confirm one.

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Dawe, Robert. "An overview of the cutaneous porphyrias." F1000Research 6 (October 30, 2017): 1906. http://dx.doi.org/10.12688/f1000research.10101.1.

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This is an overview of the cutaneous porphyrias. It is a narrative review based on the published literature and my personal experience; it is not based on a formal systematic search of the literature. The cutaneous porphyrias are a diverse group of conditions due to inherited or acquired enzyme defects in the porphyrin–haem biosynthetic pathway. All the cutaneous porphyrias can have (either as a consequence of the porphyria or as part of the cause of the porphyria) involvement of other organs as well as the skin. The single commonest cutaneous porphyria in most parts of the world is acquired porphyria cutanea tarda, which is usually due to chronic liver disease and liver iron overload. The next most common cutaneous porphyria, erythropoietic protoporphyria, is an inherited disorder in which the accumulation of bile-excreted protoporphyrin can cause gallstones and, rarely, liver disease. Some of the porphyrias that cause blistering (usually bullae) and fragility (clinically and histologically identical to porphyria cutanea tarda) can also be associated with acute neurovisceral porphyria attacks, particularly variegate porphyria and hereditary coproporphyria. Management of porphyria cutanea tarda mainly consists of visible-light photoprotection measures while awaiting the effects of treating the underlying liver disease (if possible) and treatments to reduce serum iron and porphyrin levels. In erythropoietic protoporphyria, the underlying cause can be resolved only with a bone marrow transplant (which is rarely justifiable in this condition), so management consists particularly of visible-light photoprotection and, in some countries, narrowband ultraviolet B phototherapy. Afamelanotide is a promising and newly available treatment for erythropoietic protoporphyria and has been approved in Europe since 2014.

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Bell, Toby D. M., Sheshanath V. Bhosale, Kenneth P. Ghiggino, Steven J. Langford, and Clint P. Woodward. "Synthesis and Photophysical Properties of a Conformationally Flexible Mixed Porphyrin Star-Pentamer." Australian Journal of Chemistry 62, no. 7 (2009): 692. http://dx.doi.org/10.1071/ch09142.

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The synthesis of a porphyrin star-pentamer bearing a free-base porphyrin core and four zinc(ii) metalloporphyrins, which are tethered by a conformationally flexible linker about the central porphyrin’s antipody, is described. The synthetic strategy is highlighted by the use of olefin cross metathesis to link the five chromophores together in a directed fashion in high yield. Photoexcitation into the Soret absorption band of the zinc porphyrin chromophores at 425 nm leads to a substantial enhancement of central free-base porphyrin fluorescence, indicating energy transfer from the photoexcited zinc porphyrin (outer periphery) to central free-base porphyrin. Time-resolved fluorescence decay profiles required three exponential decay components for satisfactory fitting. These are attributed to emission from the central free-base porphyrin and to two different rates of energy transfer from the zinc porphyrins to the free-base porphyrin. The faster of these decay components equates to an energy-transfer rate constant of 3.7 × 109 s–1 and an efficiency of 83%, whereas the other is essentially unquenched with respect to reported values for zinc porphyrin fluorescence decay times. The relative contribution of these two components to the initial fluorescence decay is ~3:2, similar to the 5:4 ratio of cis and trans geometric isomers present in the pentamer.

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Dinache, Andra, Simona Nistorescu, Tatiana Tozar, Adriana Smarandache, Mihai Boni, Petronela Prepelita, and Angela Staicu. "Spectroscopic Investigations of Porphyrin-TiO2 Nanoparticles Complexes." Molecules 28, no. 1 (December 30, 2022): 318. http://dx.doi.org/10.3390/molecules28010318.

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This study presents the spectral characterization of TiO2 nanoparticles (NPs) functionalized with three porphyrin derivatives: 5,10,15,20-(Tetra-4-aminophenyl) porphyrin (TAPP), 5,10,15,20-(Tetra-4-methoxyphenyl) porphyrin (TMPP), and 5,10,15,20-(Tetra-4-carboxyphenyl) porphyrin (TCPP). UV-Vis absorption and Fourier transform infrared spectroscopy–attenuated total reflection (FTIR-ATR) spectroscopic studies of these porphyrins and their complexes with TiO2 NPs were performed. In addition, the efficiency of singlet oxygen generation, the key species in photodynamic therapy, was investigated. UV-Vis absorption spectra of the NPs complexes showed the characteristic bands of porphyrins. These allowed us to determine the loaded porphyrins on TiO2 NPs functionalized with porphyrins. FTIR-ATR revealed the formation of porphyrin-TiO2 complexes, suggesting that porphyrin adsorption on TiO2 may involve the pyrroles in the porphyrin ring, or the radicals of the porphyrin derivative. The quantum yield for singlet oxygen generation by the studied porphyrin complexes with TiO2 was higher compared to bare porphyrins for TAPP and TMPP, while for the TCPP-TiO2 NPs complex, a decrease was observed, but still maintained a good efficiency. The TiO2 NPs conjugates can be promising candidates to be tested in photodynamic therapy in vitro assays.

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Thunell, S. "Porphyrins, porphyrin metabolism and porphyrias. I. Update." Scandinavian Journal of Clinical and Laboratory Investigation 60, no. 7 (January 2000): 509–40. http://dx.doi.org/10.1080/003655100448310.

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Sooambar, Chloé, Vincent Troiani, Hongjin Qiu, Sunichi Fukuzumi, Lucia Flamigni, Régis Rein, and Nathalie Solladié. "Chirality and spatially pre-organized multi-porphyrinoids." Journal of Porphyrins and Phthalocyanines 22, no. 04 (April 2018): 291–302. http://dx.doi.org/10.1142/s1088424618500396.

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We report herein that chiral and enantiopure compounds such nucleosides and peptides can pre-organize multi-porphyrinic systems and influence their properties. The first example given concerns star-shaped mutli-porphyrins with chiral and enantiopure nucleosidic linkers. If the configuration is indeed a star-shaped nanomolecule, it appears that the induced conformation is nothing as expected. The four peripheral Zn(II) porphyrins collapse over the free-base central one, inducing totally different photo-physical properties. Despite a minor expected light energy harvesting behavior, the principal capability of this system is to quench the collected light energy and convert it from radiative to non-radiative de-activation. The second example concerns polypeptides with pendant porphyrins. The peptidic backbone confers to the systems, after a certain degree of oligomerization, a 3[Formula: see text] right handed helical conformation which induces cavities within the multi-porphyrinc architecture, ready to welcome guests and render, for example, the complexation of C[Formula: see text] much easier. We thus have constructed novel organic photovoltaic systems using supramolecular complexes of porphyrin–peptide oligomers with fullerene clusters. The composite cluster OTE/SnO[Formula: see text] electrode prepared with (P(ZnP)[Formula: see text] C[Formula: see text], exhibits an impressive incident photon-to-photocurrent efficiency (IPCE) with values reaching as high as 56%. The power conversion efficiency of the (P(H[Formula: see text]P)[Formula: see text] C[Formula: see text] modified electrode reaches 1.6%, which is 40 times higher than the value (0.043%) of the porphyrin monomer (P(H[Formula: see text]P)[Formula: see text] [Formula: see text] C[Formula: see text] modified electrode. Thus, the organization approach between porphyrins and fullerenes with polypeptide structures is promising, and may make it possible to further improve the light energy conversion properties by using a larger number of porphyrins in a polypeptide unit.

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23

Kaczynski, Jerzy, Göran Hansson, and Sven Wallerstedt. "Increased Porphyrins in Primary Liver Cancer Mainly Reflect a Parallel Liver Disease." Gastroenterology Research and Practice 2009 (2009): 1–6. http://dx.doi.org/10.1155/2009/402394.

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Hepatic porphyries have been associated with an increased risk of primary liver cancer (PLC), which on the other hand may cause an increased porphyrin production. To evaluate the role of an underlying liver disorder we analyzed porphyrins in patients with hepatocellular carcinoma (HCC)(n=65), cholangiocellular carcinoma(n=3), or suspected PLC, which turned out to be metastases(n=18)or a benign disorder(n=11). None of the patients had a family history of porphyry or clinical signs of porphyry. Increased aminolevulinic acid or porphyrin values were common not only in patients with PLC (43%) but also in metastatic (50%) and benign (64%) liver disorders. The corresponding proportion for HCC patients with liver cirrhosis (55%) was higher(P<.05)than in those without cirrhosis (17%). We conclude that symptomatic porphyries are unusual in PLC, whereas elevated urinary and/or faecal porphyrins are common, primarily reflecting a parallel liver disease and not the PLC.

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24

Uemori, Yoshio, Masato Sakurai, Atsuko Osada, Hiroki Munakata, Hiroyasu Imai, and Shigeo Nakagawa. "Synthesis and properties of water-soluble porphyrins bearing multidentate ligands." Journal of Porphyrins and Phthalocyanines 08, no. 08 (August 2004): 1047–54. http://dx.doi.org/10.1142/s1088424604000416.

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Water-soluble porphyrins bearing multidentate ligands were prepared by covalent binding of nitrilotriacetic acid to 5,10,15,20-tetrakis(4-aminophenyl)porphyrin or three atropisomers of 5,10,15,20-tetrakis(2-aminophenyl)porphyrin. The acid-base properties and monomer-dimer behavior of the porphyrins were affected by the positions of the multidentate ligands with respect to the porphyrin plane. Among the porphyrins, the porphyrin bearing multidentate ligands at the para position of the phenyl groups dimerized in an aqueous solution. The association constants of the porphyrins with various aromatic compounds were studied in water at pH 7.4 containing 10 mM HEPES at 25°C. These values varied with the structure and charges of both the porphyrins and the aromatic compounds. The association constants of the porphyrin bearing multidentate ligands at the 2-position of the phenyl groups were small compared to those of the porphyrin bearing multidentate ligands at the 4-position.

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25

Bakali, E. El, H. Kerrouch, R. El Chafi, T. Hanafi, Y. Zemmez, R. Frikh, and N. Hjira. "PORPHYRIA CUTANEATARDA: A CASE REPORT." International Journal of Advanced Research 11, no. 03 (March 31, 2023): 997–1000. http://dx.doi.org/10.21474/ijar01/16524.

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Porphyria cutaneatarda (PCT) is a rare disease of porphyrin metabolism, related to a deficiency of Uroporphyrinogen decarboxylase activity. Clinically, it manifests itself by a skin fragility in photo-exposed areas. The characteristic biochemical profile of PCT, with elevated levels of urinary and plasma porphyrins, establishes the diagnosis. Treatment is based on phlebotomy, hydroxychloroquine (100 to 200 mg twice weekly) and control of susceptibility factors. We report a case of porphyria cutaneatarda in a male coast guard by profession.

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26

Lai, C. K., C. W. Lam, and Y. W. Chan. "High-performance thin-layer chromatography of free porphyrins for diagnosis of porphyria." Clinical Chemistry 40, no. 11 (November 1, 1994): 2026–29. http://dx.doi.org/10.1093/clinchem/40.11.2026.

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Abstract In this simple high-performance thin-layer chromatographic technique for evaluating porphyrin excretion, porphyrins rapidly extracted from urine or feces are separated on reversed-phase octadecylsilyl (C18)-bonded silica thin-layer chromatography plates. We observed > 12 distinct bands of different porphyrins by viewing the plates under long-wave ultraviolet light. Positive screening tests can readily be characterized by the relative fluorescence of various free porphyrins. The two patients presented in this paper are possibly the first two cases of porphyria cutanea tarda reported in Hong Kong Chinese.

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27

Zuijderhoudt, F. M. J., J. Dorresteijn-De Bok, and K. Te Velde. "Evaluation of a First-Line Spectrophotometric Screening Test for Increased Urine Porphyrin Excretion." Annals of Clinical Biochemistry: International Journal of Laboratory Medicine 32, no. 2 (March 1995): 186–89. http://dx.doi.org/10.1177/000456329503200209.

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We compared a spectrophotometric screening test for urine porphyrin concentration with a high performance liquid chromatography (HPLC) method. The screening test gave lower values than those obtained by HPLC, but the overall correlation was good. Occasionally, spectrophotometry failed to detect porphyrins in the urine which were detected by HPLC. The type of porphyria had no influence on the efficacy of the screening method. Receiver operating characteristic plot analysis of the screening test led to a cut-off value of 110 nmol/24 h with a sensitivity of 96% and a specificity of 86%. We conclude that the spectrophotometric screening method is useful for detection of increased total urine porphyrin concentration.

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28

Buraga, Ioan, and Adrian-Florin Dobrescu. "19-year-old female with abdominal pain." Romanian Journal of Neurology 12, no. 1 (March 31, 2013): 30–36. http://dx.doi.org/10.37897/rjn.2013.1.4.

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Porphyria is a group of at least 8 diseases that differ greatly between them. Common feature of these diseases is the accumulation in the body of porphyrins or porphyrin precursors, due to defects of specific enzymes in the biosynthesis of hem. Many symptoms of porphyria are nonspecific and therefore the diagnosis is often delayed. Laboratory tests can confirm or exclude the diagnosis of porphyria. However, certain diagnosis requires demonstration of specific enzyme deficiency. The presented case demonstrates the difficulty in diagnosis of acute intermittent porphyria (AIP) in a young woman without a history of significant pathology.

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29

Teplyuk, N. P., Ekaterina Yu Vertieva, D. V. Ignatyev, and I. S. Dzhavakhishvili. "Porphyria cutanea tarda concomitant with chronic hepatitis C." Russian Journal of Skin and Venereal Diseases 19, no. 1 (February 15, 2016): 17–20. http://dx.doi.org/10.18821/1560-9588-2016-19-1-17-20.

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Porphyrias form a group of rare metabolic diseases associated with disorders in the heme biosynthesis enzymes, leading to porphyrin accumulation in tissues. The disease is rare and is often diagnosed too late. The most incident is porphyria cutanea tarda. All patients with this condition should be tested for viral hepatites and hemochromatosis. A clinical case is presented: a patient with porphyria cutanea tarda associated with alcohol abuse and viral hepatitis C.

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30

Gao, Yi, Ji Gang Pan, Yue Jun Huang, Shuang Yan Ding, and Meng Liang Wang. "Microwave-assisted synthesis of fluorine substituted porphyrins and kinetics of formation of zinc porphyrin complexes in acetic acid." Journal of Porphyrins and Phthalocyanines 19, no. 12 (December 2015): 1251–55. http://dx.doi.org/10.1142/s1088424615501096.

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Three mono-fluorine substituted porphyrin compouds were synthesized under microwave irradiation. The effects of catalysts and oxidants on the yields of mono-fluorine substituted porphyrins also were investigated. The yields of 5,10,15,20-tetrakis(4-fluorophenyl)porphyrin, 5,10,15,20-tetrakis(3-fluorophenyl)porphyrin, 5,10,15,20-tetrakis(2-fluorophenyl)porphyrin in a use of nitrobenzene in propionic acid were 36%, 30% and 28%, respectively. In addition, the zinc(II) ion incorporation reactions into porphyrins to form the zinc porphyrin complexes have been kinetically investigated in acetic acid.

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31

Qi, Zhen-Li, Yun-Hui Cheng, Zhou Xu, and Mao-Long Chen. "Recent Advances in Porphyrin-Based Materials for Metal Ions Detection." International Journal of Molecular Sciences 21, no. 16 (August 14, 2020): 5839. http://dx.doi.org/10.3390/ijms21165839.

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Porphyrins have planar and conjugated structures, good optical properties, and other special functional properties. Owing to these excellent properties, in recent years, porphyrins and their analogues have emerged as a multifunctional platform for chemical sensors. The rich chemistry of these molecules offers many possibilities for metal ions detection. This review mainly discusses two types of molecular porphyrin and porphyrin composite sensors for metal ions detection, because porphyrins can be functionalized to improve their functional properties, which can introduce more chemical and functional sites. According to the different application materials, the section of porphyrin composite sensors is divided into five sub-categories: (1) porphyrin film, (2) porphyrin metal complex, (3) metal–organic frameworks, (4) graphene materials, and (5) other materials, respectively.

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32

Shee, Nirmal Kumar, Min Kyoung Kim, and Hee-Joon Kim. "Supramolecular Porphyrin Nanostructures Based on Coordination-Driven Self-Assembly and Their Visible Light Catalytic Degradation of Methylene Blue Dye." Nanomaterials 10, no. 11 (November 22, 2020): 2314. http://dx.doi.org/10.3390/nano10112314.

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A series of porphyrin triads (1–4), in which each triad is composed of a Sn(IV) porphyrin and two free-base (or Zn(II)) porphyrins, was synthesized and their self-assembled nanostructures were studied. Depending on the substituent on porphyrin moieties, each triad was self-assembled into a different nanostructure. In particular, the cooperative coordination of 3-pyridyl groups in the Sn(IV) porphyrin with the axial Zn(II) porphyrins in triad 4 leads to forming uniform nanofibers with an average width of 10–22 nm. Other triads without the coordinating interaction between the central Sn(IV) porphyrin and the axial porphyrins formed irregularly shaped aggregates in contrast. The morphologies of nanofiber changed drastically upon the addition of pyrrolidine, in which pyrrolidine molecules break down the self-assembly process by coordinating with the axial Zn(II) porphyrins. All porphyrin aggregates exhibited efficient photocatalytic performances on the degradation of methylene blue dye under visible light irradiation. The degradation efficiencies after 2 h were observed to be between 70% and 95% for the aggregates derived from the four triads.

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33

Gross, Ulrich, Shigeru Sassa, Karl Jacob, Jean-Charles Deybach, Yves Nordmann, Margareta Frank, and Manfred O. Doss. "5-Aminolevulinic acid dehydratase deficiency porphyria: a twenty-year clinical and biochemical follow-up." Clinical Chemistry 44, no. 9 (September 1, 1998): 1892–96. http://dx.doi.org/10.1093/clinchem/44.9.1892.

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Abstract 5-Aminolevulinic acid dehydratase (ALAD) activity in two patients with compound heterozygous 5-aminolevulinic acid dehydratase deficiency porphyria was studied over the last 20 years. The patients’ enzyme activity was <10% from 1977 to 1997. An acute crisis in each patient was successfully treated by infusion of glucose and heme arginate. After this therapy both urinary 5-aminolevulinic acid (ALA) and total porphyrins were diminished to 65% in patient B. In patient H, ALA was decreased to 80%, and total porphyrins were reduced to 15% after treatment with heme arginate and glucose. The patients remained free of symptoms after this therapy. Family studies of patient B showed cross-reactive immunological material (CRIM), in which the maternal mutation is CRIM(+), whereas the paternal mutation is CRIM(−). Incubation of erythrocyte lysates with ALA decreased porphyrin formation, whereas incubation with porphobilinogen produced porphyrin concentrations within reference values in both patients, confirming that ALAD activity is rate-limiting in these cells.

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34

YUAN, HONGPING, and L. KEITH WOO. "Synthesis and Characterization of Thiol-Derivatized Porphyrins and Metalloporphyrin complexes." Journal of Porphyrins and Phthalocyanines 01, no. 02 (April 1997): 189–200. http://dx.doi.org/10.1002/(sici)1099-1409(199704)1:2<189::aid-jpp23>3.0.co;2-g.

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A series of thiol-derivatized porphyrins and the corresponding cobalt and zinc complexes were synthesized from 5-(p-aminophenyl)-10,15,20-triphenylporphyrin ( H 2 TPP - NH 2), and 5α,15α-bis(o-aminophenyl)porphyrin ( H 2 DPE - ( NH 2)2). These derivatized porphyrins have a different number of thiol appendages attached via amide linkages at different locations. The thiol-derivatized porphyrins made from H 2 TPP - NH 2, H 2 TPP - NHC ( O )( CH 2) n SH ( n = 2, 4, 5, 10), have one alkyl-thiol appendage attached to the porphyrin through an amide linkage on the p-aminophenyl position. The derivatives made from H 2 DPE -( NH 2)2 have two alkyl-thiol appendages attached to the porphyrin through amide linkages on the o-aminophenyl positions on the same face of the porphyrin ring. These thiol-derivatized porphyrins are important adsorbates for the preparation of thiol–porphyrin monolayers on gold.

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35

Prasad, Sana Siva, Bandameeda Ramesh Naidu, Marlia M. Hanafiah, Jangam Lakshmidevi, Ravi Kumar Marella, Sivarama Krishna Lakkaboyana, and Katta Venkateswarlu. "Porphyrin N-Pincer Pd(II)-Complexes in Water: A Base-Free and Nature-Inspired Protocol for the Oxidative Self-Coupling of Potassium Aryltrifluoroborates in Open-Air." Molecules 26, no. 17 (September 4, 2021): 5390. http://dx.doi.org/10.3390/molecules26175390.

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Metalloporphyrins (and porphyrins) are well known as pigments of life in nature, since representatives of this group include chlorophylls (Mg-porphyrins) and heme (Fe-porphyrins). Hence, the construction of chemistry based on these substances can be based on the imitation of biological systems. Inspired by nature, in this article we present the preparation of five different porphyrin, meso-tetraphenylporphyrin (TPP), meso-tetra(p-anisyl)porphyrin (TpAP), tetrasodium meso-tetra(p-sulfonatophenyl)porphyrin (TSTpSPP), meso-tetra(m-hydroxyphenyl)porphyrin (TmHPP), and meso-tetra(m-carboxyphenyl)porphyrin (TmCPP) as well as their N-pincer Pd(II)-complexes such as Pd(II)-meso-tetraphenylporphyrin (PdTPP), Pd(II)-meso-tetra(p-anisyl)porphyrin (PdTpAP), Pd(II)-tetrasodium meso-tetra(p-sulfonatophenyl)porphyrin (PdTSTpSPP), Pd(II)-meso-tetra(m-hydroxyphenyl)porphyrin (PdTmHPP), and Pd(II)-meso-tetra(m-carboxyphenyl)porphyrin (PdTmCPP). These porphyrin N-pincer Pd(II)-complexes were studied and found to be effective in the base-free self-coupling reactions of potassium aryltrifluoroborates (PATFBs) in water at ambient conditions. The catalysts and the products (symmetrical biaryls) were characterized using their spectral data. The high yields of the biaryls, the bio-mimicking conditions, good substrate feasibility, evading the use of base, easy preparation and handling of catalysts, and the application of aqueous media, all make this protocol very attractive from a sustainability and cost-effective standpoint.

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36

Baytaeva, D. A., and S. S. Bessmel’tsev. "Porphyrin metabolism in secondary hepatic porphyria in patients with hereditary deficiency of glucose-6-phosphate dehydrogenase." Kazan medical journal 93, no. 3 (June 15, 2012): 451–55. http://dx.doi.org/10.17816/kmj1865.

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Aim. The study the porphyrin metabolism during the development of secondary hepatic porphyria in patients with glucose-6-phosphate dehydrogenase deficiency. Methods. Examined were 148 male patients aged 5-19 years (median 12 years) with impaired activity of glucose-6-phosphate dehydrogenase in combination with β-thalassemia and without it. Qualitative and quantitative methods of examining the activity of this enzyme were used in order to verify the diagnosis. Taking into account the varying degree of glucose-6-phosphate dehydrogenase deficiency, the indices of metabolism of the enzyme and of the porphyrins were correlated with the severity of anemia, functional liver capacities, with parameters reflecting iron content in blood serum, bone marrow, liver and urine. The markers of intoxication were also taken into account in the development of secondary hepatic porphyria and endotoxemia. Therapeutic plasmapheresis was used to correct the revealed disorders. Results. The influence of glucose-6-phosphate dehydrogenase deficiency on the metabolism of porphyrins and liver functional status has been shown, which leads to the development of anemia and endogenous intoxication. With the help of parameters, which characterize the porphyrin metabolism in patients, secondary hepatic porphyria was revealed. It was established that determination of the content of glucose-6-phosphate dehydrogenase and porphyrins makes it possible to detect disturbances in heme synthesis at an early stage and to evaluate the compensatory abilities of the liver. An important diagnostic feature for glucose-6-phosphate dehydrogenase deficiency, regardless of severity, is the impaired synthesis of the end products of metabolism of porphyrins - uro-, copro- and protoporphyrin. The effectiveness of therapeutic plasmapheresis for hemolysis, secondary hepatic porphyria and endogenous intoxication has been shown. Conclusion. Increased excretion of uro-and coproporphyrin with urine reflects the severity of endotoxemia, and is an alternative to markers of intoxication; high concentration of free protoporphyrin and low concentration of uro- and coproporphyrin in erythrocytes is an important diagnostic sign of impaired activity of glucose-6-phosphate dehydrogenase in patients.

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37

Abe, K., and R. Konaka. "Quantification of urinary porphyrins by liquid chromatography after oxidation of porphyrinogens." Clinical Chemistry 35, no. 8 (August 1, 1989): 1619–22. http://dx.doi.org/10.1093/clinchem/35.8.1619.

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Abstract A quantitative "high-performance" liquid-chromatographic method is described for determining porphyrins in human urine. Porphyrinogens in urine are first converted to the corresponding porphyrins by oxidation with iodine. Uroporphyrin, hepatacarboxylic acid porphyrin, hexacarboxylic acid porphyrin, pentacarboxylic acid porphyrin, and coproporphyrin I and III isomers are then separated on a reversed-phase column and measured by fluorometry. Analysis for the six porphyrins is complete within 24 min, including reconditioning for the next sample. The detection limit (twice the signal/noise ratio) for each porphyrin was 1 nmol/L for urine (25 fmol per 50-microL injection). Mean analytical recovery of each porphyrin ranged from 85% to 91%, within-day CVs from 1.4% to 7.3%. Normal reference intervals for porphyrins were established by assaying urine samples from 75 healthy subjects. Significant sex-related differences in coproporphyrin I and III isomers were evident when the values were expressed as nanomoles per gram of creatinine. Coproporphyrin isomer ratio was estimated for utility in the diagnosis of porphyrinurias.

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Imahori, Hiroshi, and Tomokazu Umeyama. "Porphyrin-modified electrodes for solar energy conversion." Journal of Porphyrins and Phthalocyanines 13, no. 10 (October 2009): 1063–68. http://dx.doi.org/10.1142/s1088424609001315.

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This mini review presents our recent developments in porphyrin-modified electrodes for solar energy conversion. Various porphyrins have been assembled on nanostructured semiconducting electrodes to achieve efficient photocurrent generation. First, porphyrins have been organized with fullerenes onto semiconducting electrodes to elucidate the relationship between the molecular structures, film structures, and photoelectrochemical properties of the modified electrodes. Formation of hole and electron-transporting highways in the porphyrin/fullerene composite film led to the remarkable enhancement of photocurrent generation. Second, porphyrin-modified single-walled carbon nanotubes have also been assembled onto semiconducting electrodes. The degree of chemical functionalization by the bulky porphyrins was found to have a large impact on the photoelectrochemical properties. Third, asymmetrically π-elongated porphyrins have been successfully employed in dye-sensitized solar cells to improve the cell performance as well as the light-harvesting properties. The power conversion efficiency of the fused porphyrin cell was improved by 50% compared to the reference cell using the corresponding unfused porphyrin. Finally, carboxyquinoxalino derivatives of zinc porphyrin have been further developed to extend the concept of asymmetrically π-elongated porphyrins. The maximum power conversion efficiency of 5.2% was obtained by using 5,10,15,20-tetrakis(2,4,6-trimethylphenyl)-6′-carboxyquinoxalino[2,3-b]porphyrinatozinc(II).

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39

Wenceslau, Adriana C., Guilherme L. Q. C. Ferreira, Noboru Hioka, and Wilker Caetano. "Spectroscopic studies of pyridil and methoxyphenyl porphyrins in homogeneous and Pluronic®-based nanostructured systems." Journal of Porphyrins and Phthalocyanines 19, no. 11 (November 2015): 1168–76. http://dx.doi.org/10.1142/s1088424615500996.

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Spectroscopic properties of Porphyrins TPyP (tetra(4-pyridil)porphyrin), TMPP (tetrakis(4-methoxypheny) porphyrin) and its zinc metaled derivatives porphyrins Zn-TPyP and Zn-TMPP respectively, were studied in homogeneous and micro heterogeneous systems, comprising nanostructured Pluronic® copolymeric micellar systems, as a promising drug delivery systems for the porphyrins investigated. Physico-chemical properties such as, hydrophobicity degree, self- aggregation in solvents of different polarities and water/ethanol mixtures (monofasic binary), as well as kinetics profile and isotherm binding, molecular organization, [Formula: see text] and relative localization in neutral micellar systems. The hydrophobic character was the key to relative drug location in the micellar systems. In homogenous solvents systems the porphyrins presented relatively high values of molar absorptivity and low values of [Formula: see text]. The K[Formula: see text] values obtained are modulated by the structure of porphyrins, state of aggregation, as well as, structure and macro molecular self-organization of copolymers. Fluorescence quenching studies have shown that porphyrins in F-127 are located in a less hydrophobic region than the porphyrins in P-123, which are located preferentially in a deeper micellar microenvironment. The zinc porphyrins showed high values of K[Formula: see text]. Thus, the association of the porphyrins with specific binding sites of micellar systems is strongly modulated by the presence of the metal coordinated to the porphyrinic ring.

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40

Czekaj, Aleksandra, Kinga Ruszel, Robert Dubel, Julia Dubel, and Natalia Namroży. "Acute hepatic porphyria - classification, diagnosis and treatment." Journal of Education, Health and Sport 13, no. 1 (November 25, 2022): 117–22. http://dx.doi.org/10.12775/jehs.2023.13.01.019.

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Porphyrias belong to the group of inherited metabolic diseases. Each of the four types of acute hepatic porphyria is caused by a different mutation in the gene of an enzyme involved in the heme biosynthetic pathway. The literature distinguishes between: Acute Intermittent Porphyria (AIP), Hereditary Coproporphyria (HCP), Variegate Porphyria (VP) and Aminolevulinic Dehydratic ADP (ADP) deficiency. -deficient Porphyria). Deficiency of individual enzymes leads to ineffective heme production and accumulation of neurotoxic intermediates - the so-called porphyrins. Two excess metabolites are of major importance in diagnostics - ALA (amionolevulinic acid) and PBG (porphobilinogen). In most cases, the activity of the less functional enzyme is so high that the disease never becomes apparent (latent form). Excessive accumulation of porphyrin precursors is associated with exposure to porphyrinogenic factors, leading to a seizure whose symptoms are closely related to autonomic, peripheral neuropathy, and accompanying neuropsychiatric disorders. In diagnostics, particular attention should be paid to the circumstances of the symptoms and the history of the patient's disease, which often includes numerous episodes of unexplained abdominal pain, which was so severe that it forced the patient to report to emergency departments. A severe attack of porphyria is a medical emergency and requires hospitalization. Failure to diagnose or properly treat it may result in flaccid tetraplegia, respiratory failure, brain edema, coma, and sudden circulation detention.

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41

Zvezdina, S. V., N. V. Chizhova, and N. Z. Mamardashvili. "Complex formation of halogen substituted tetraphenylporphyrins and Cd(II)-tetraphenylporphyrins with MnCl2 in DMF." Журнал органической химии 59, no. 4 (April 15, 2023): 475–85. http://dx.doi.org/10.31857/s0514749223040067.

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Reactions of complex formation of 5,10,15,20-tetra-(2,6-dichlorophenyl)porphyrin, 5,10,15,20-tetra-(2,6-difluorophenyl)porphyrin and metal exchange of their cadmium complexes with manganese chloride(II) in dimethylformamide were investigated. ortho -Substituted manganese complexes were synthesized by prolonged refluxing of the corresponding porphyrins with an excess of MnCl2 in dimethylformamide. Using the metal exchange reaction of Cd(II)-5,10,15,20-tetra-(2,6-dichlorophenyl)porphyrin and Cd(II)-5,10,15,20-tetra-(2,6-difluorophenyl) porphyrin, the corresponding Mn(III)-tetraphenylporphyrins were obtained. On the contrary, the coordination reactions of porphyrins substituted at the pyrrole and phenyl rings with manganese chloride in dimethylformamide proceed under mild conditions with the formation of complexes Mn(II)-2,3,7,8,12,13,17,18-octabromo-5,10,15,20-tetra-(2,6-dichlorophenyl)porphyrin [the compound oxidizes in air to a mixture of Mn(II) and Mn(III)-porphyrins] and Mn(II)-2,3,7,8,12,13,17,18-octachloro-5,10,15,20-tetra-(2,6-difluorophenyl)porphyrin. The synthesized compounds were identified using UV-Vis, 1H NMR spectroscopy and mass-spectrometry. Metal exchange reaction of ortho -substituted Cd(II)-porphyrins and complex formation of 2,3,7,8,12,13,17,18-octabromo-5,10,15,20-tetra-(2,6-dichlorophenyl)porphyrin with manganese chloride in dimethylformamide were studied by the spectrophotometric method. The kinetic parameters of the reactions were calculated. A strong effect of β- and ortho -substitution on the reactions of complex formation and metal exchange of the studied compounds was found.

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42

Lambie, Deborah, Chris Florkowski, Chris Sies, Anthony Raizis, Wai-Kwan Siu, and Cindy Towns. "A case of hereditary coproporphyria with posterior reversible encephalopathy and novel coproporphyrinogen oxidase gene mutation c.863T>G (p.Leu288Trp)." Annals of Clinical Biochemistry: International Journal of Laboratory Medicine 55, no. 5 (April 27, 2018): 616–19. http://dx.doi.org/10.1177/0004563218774597.

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A 21-year-old female had recurrent presentations to the emergency department with myalgia, vomiting, abdominal pain and subsequently developed generalized seizures. She was volume depleted with a plasma sodium of 125 mmol/L (reference interval: 135–145) and she had fluctuating hypertension. Acute porphyria was suspected and confirmed with raised urine porphobilinogen/creatinine ratio of 12:4 μmol/mmoL (reference interval < 1:5) and she was treated with intravenous haem arginate. Urinary porphyrin/creatinine ratio was 673 nmol/mmoL (reference interval <35) and faecal porphyrins 2430 μmol/kg dry weight (reference interval: <200) were markedly elevated, with raised faecal CIII:CI ratio, consistent with acute coproporphyria. Diagnosis was confirmed by the demonstration of a novel missense variant in the coproporphyrinogen oxidase gene c.863T > G (p.Leu288Trp) predicted to be deleterious and which segregated with three other affected family members. Although CT head was normal, magnetic resonance imaging scan revealed symmetrical signal abnormalities and swelling in the parietal and occipital lobes consistent with posterior reversible encephalopathy. Over several days, her seizures ceased and sodium and blood pressure normalized. The aetiology of the acute porphyric attack was likely multifactorial with contributions from a recent viral illness and caloric deprivation. No drug precipitant was identified. We postulate that untreated hypertension played a key role in the development of posterior reversible encephalopathy. Early clinical suspicion and urine porphobilinogen testing are the key components in preventing morbidity and mortality in acute porphyrias.

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Peng, Cheng-Liang, Ping-Shan Lai, and Ming-Jium Shieh. "INFLUENCE OF SUBSTITUTIONS IN ASYMMETRIC PORPHYRINS ON INTRACELLULAR UPTAKE, SUBCELLULAR LOCALIZATION AND PHOTOTOXICITY IN HELA CELLS." Biomedical Engineering: Applications, Basis and Communications 20, no. 01 (February 2008): 9–17. http://dx.doi.org/10.4015/s1016237208000556.

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The asymmetric porphyrins with different substituents show various bioactivities in biomedical application. In this study, a series of asymmetric porphyrins with varying proportion of substituents, such as hydroxyphenyl and aminophenyl, were synthesized and characterized to evaluate their cell uptake, intracellular localization, cytotoxicities and phototoxicities in vitro. Among these synthesized porphyrins, 5-(4-aminophenyl)-10,15,20-tri-(4-hydroxyphenyl)-21,23H-porphyrin (porphyrin 5), which was mainly localized in mitochondria and with high quantum yields of singlet oxygen, is a potential candidate for photodynamic therapy. The effective phototoxicity of porphyrin 5 is mainly due to the higher extent in the cells and the selective mitochondria-localization. Comparing the partition coefficients of porphyrin derivatives, the best cellular uptake performs apparently with a partition coefficient (log p) ranging from about 1.7 to 1.9. In summary, higher quantum yields of singlet oxygen, and more specific mitochondrial localization of porphyrin 5 demonstrate its potential application in photodynamic therapy.

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44

Cohen, Brian A., Alain E. Kaloyeros, and Magnus Bergkvist. "Nucleotide-driven packaging of a singlet oxygen generating porphyrin in an icosahedral virus." Journal of Porphyrins and Phthalocyanines 16, no. 01 (January 2012): 47–54. http://dx.doi.org/10.1142/s1088424611004324.

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Results are reported from investigations of the interactions between MS2 bacteriophages and a cationic porphyrin with potential use in photodynamic therapy. Based on the naturally strong binding between porphyrins and nucleic acids, it is suggested that this non-enveloped capsid could act as a self-loading, nanoscale carrier of porphyrins. By applying size exclusion chromatography in conjunction with UV-vis and fluorescence spectroscopy, it is demonstrated that approximately 250 porphyrin molecules could associate and co-elute with a single capsid. Additionally, there is an observed red shift in the Soret peak of the porphyrin, indicating that the majority of the cationic porphyrin is capable of interacting with RNA on the interior of the capsid. It is also observed that removal of RNA from the interior of the MS2 capsid significantly reduces loading capacity of the porphyrin. Furthermore, MS2 bacteriophages loaded with porphyrins were shown to photogenerate singlet oxygen. These findings suggest that icosahedral viruses, such as MS2 bacteriophages, are able to function as self-packaging "nanoscale containers" and efficiently load cationic porphyrins, with potential benefits in areas such as targeted photodynamic therapy.

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45

Almeida, José, Maria E. Fortună, Lucia Pricop, Andrei Lobiuc, Andreia Leite, André M. N. Silva, Rodrigo P. Monteiro, Maria Rangel, Valeria Harabagiu, and Ana M. G. Silva. "(Aminophenyl)porphyrins as precursors for the synthesis of porphyrin-modified siloxanes." Journal of Porphyrins and Phthalocyanines 23, no. 09 (September 2019): 1001–12. http://dx.doi.org/10.1142/s1088424619500573.

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The present research reports the efficient synthesis of mono- and di-(aminophenyl)porphyrins and their metalation with Zn(II) using microwave irradiation. The subsequent reaction of amino-functionalized porphyrins with siloxane moieties bearing epoxy or carboxyl functional groups provided four new porphyrin-modified siloxanes. The structure of the resulting derivatives was established by 1H-NMR and MALDI-TOF-MS. The optical properties of the porphyrin chromophores were preserved, as proven by comparing the absorption and emission spectra of the initial porphyrins to those of the porphyrin-modified siloxanes.

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46

Lamare, R., L. Ruhlmann, R. Ruppert, and J. Weiss. "Case studies of the radical cation reactivity in meso-aryl and octaethyl porphyrins." Journal of Porphyrins and Phthalocyanines 24, no. 05n07 (May 2020): 860–68. http://dx.doi.org/10.1142/s1088424619501980.

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The reactivity of porphyrin radical cationic species derived from octaethyl porphyrin (OEP) or meso-aryl porphyrins with nucleophiles, envisioned as an access route to elaborate porphyrin dimers, has been studied and optimized in the case of OEP. Standardized conditions have been applied to various spacers to show that the success of the reaction is mostly nucleophile dependent and that the method has little chances to yield non-linear bis-porphyrins.

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Blart, Errol, Franck Suzenet, Jean-Paul Quintard, and Fabrice Odobel. "Preparation of novel highly conjugated bis-porphyrin bridged with a polyene linker." Journal of Porphyrins and Phthalocyanines 07, no. 04 (April 2003): 207–13. http://dx.doi.org/10.1142/s1088424603000288.

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This paper describes the preparation of a bis free-base porphyrin and a bis-zinc porphyrin system in which the two 5,10,15-tris(3,5-ditertbutylphenyl)porphyrinyl units are connected in meso position by a tetraenic chain. The preparation of the dyad relies on the Wittig-Horner-Emmons reaction between diethyl 3-[5-[10,15,20-tris(3,5-ditert-butyl-phenyl)-porphyrinyl]] prop-2-enyl phosphonate and the aldehyde-1,3-diene[5-[10,15,20-tris(3,5-ditert-butyl-phenyl)-porphyrinyl]]. The two latter porphyrin derivatives were obtained via a Stille cross-coupling reaction between the corresponding tributyltin derivatives and the 5-iodo-10,15,20-tris(3,5-ditert-butyl-phenyl)-porphyrin. The UV-visible absorption and fluorescence spectra of the bis-porphyrin systems are measured and indicate that both the energy level and the lifetime of the porphyrin singlet excited state are reduced upon the attachment of the polyene chain to the porphyrin unit.

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48

Beyler, Maryline, Valérie Heitz, Julien Taesch, and Jean-Pierre Sauvage. "Templated synthesis of catenanes incorporating Zn(II) or Rh(III)-complexed porphyrins: the coordination chemistry-only approach." Journal of Porphyrins and Phthalocyanines 15, no. 09n10 (September 2011): 848–57. http://dx.doi.org/10.1142/s1088424611004002.

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Porphyrin-containing [2]catenanes were obtained from relatively simple organic precursors thanks to "coordination chemistry-only". When the central porphyrin metal is Zn2+ the [2]catenanes were assembled in two steps by using Cu(I)–N interactions to assemble acyclic complexes and Zn(II)–N interactions to generate rings. These sophisticated architectures were obtained in excellent yield since the formation of the thermodynamic products is favored over that of kinetic products. This also explains why a perfect fit in terms of distances and angles between the components to assemble leads to highly stable coordination chemistry-assembled species. When a second row metal with an inert coordination sphere, like Rh(III) was chosen as metal centre of the porphyrins, direct metalation of porphyrinic compounds with [Rh(CO)2Cl]2 was not met with success when the bidentate chelate used as connector was metal free. A three-step strategy was used for the synthesis of a tetra-rhodiumporphyrin[2]-catenane: (i) copper(I)-driven entwining of two free-base porphyrin-bearing bidentate chelates followed (ii) by insertion of rhodium in the porphyrin nuclei and finally (iii) cyclisation via formation of N-Rh coordination bonds.

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Alpatova, Victoria M., Evgeny G. Rys, Elena G. Kononova, and Valentina A. Ol'shevskaya. "Synthesis of new representatives of A₃B-type carboranylporphyrins based on meso-tetra(pentafluorophenyl)porphyrin transformations." Beilstein Journal of Organic Chemistry 20 (April 12, 2024): 767–76. http://dx.doi.org/10.3762/bjoc.20.70.

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A carboranylporphyrin of A3B-type bearing a single pentafluorophenyl ring was prepared through the regioselective nucleophilic aromatic substitution reaction of the p-fluorine atoms in 5,10,15,20-tetrakis(pentafluorophenyl)porphyrin with 9-mercapto-m-carborane. The reaction of this porphyrin with sodium azide led to the selective substitution of the p-fluorine atom in the pentafluorophenyl substituent with an azide functionality which upon reduction with SnCl2 resulted in the formation of the corresponding porphyrin with an amino group. Pentafluorophenyl-substituted A3B-porphyrins were studied and transformed to thiol and amino-substituted compounds allowing for the preparation of porphyrins with different reactive groups such as hydroxy and amino derivatives capable for further functionalization and conjugation of these porphyrins to other substrates. In addition, conjugates containing maleimide or biotin entities in the structure of carborane A3B-porphyrin were also synthesized based on the amino-substituted A3B-porphyrin. The structures of the prepared carboranylporphyrins were determined by UV–vis, IR, 1H, 19F, 11B NMR spectroscopic data and MALDI mass spectrometry.

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50

Yan, Guo-Ping, Kathryn E. Fairfull-Smith, Craig D. Smith, Graeme R. Hanson, and Steven E. Bottle. "Porphyrin containing isoindoline nitroxides as potential fluorescence sensors of free radicals." Journal of Porphyrins and Phthalocyanines 15, no. 04 (April 2011): 230–39. http://dx.doi.org/10.1142/s1088424611003203.

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A series of new spin-labeled porphyrin containing isoindoline nitroxide moieties were synthesized and characterized as potential free radical fluorescence sensors. Fluorescence-suppression was observed in the free-base monoradical porphyrins, whilst the free-base biradical porphyrins exhibited highly suppressed fluorescence about three times greater than the monoradical porphyrins. The observed fluorescence-suppression was attributed to enhanced intersystem crossing resulting from electronexchange between the doublet nitroxide and the excited porphyrin fluorophore. Notably, fluorescencesuppression was not as strong in the related metalated porphyrins, possibly due to insufficient spin coupling between the nitroxide and the porphyrin. Continuous wave EPR spectroscopy of the diradical porphyrins in fluid solution suggests that the nitroxyl-nitroxyl interspin distance is long enough and tumbling is fast enough not to detect dipolar coupling.

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Journal articles on the topic 'Porphyrin'

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