Journal articles: 'Spectroscopic and physicochemical techniques'

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Tirkkonen, B., A. Aukrust, E. Couture, D. Grace, Y. Haile, K. M. Holm, H. Hope, Å. Larsen, H. Sivertsen Lunde, and C. E. Sjøgren. "Physicochemical characterisation of mangafodipir trisodium." Acta Radiologica 38, no. 5 (September 1997): 780–89. http://dx.doi.org/10.1080/02841859709172411.

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Purpose: To determine the structure and various physicochemical properties of man-gafodipir (MnDPDP) trisodium, the active ingredient of Teslascan, a new organ-specific contrast medium for MR imaging. Material and Methods: The structure of MnDPDP trisodium crystals was determined by X-ray crystallography. The possible existence of polymorphism in MnDPDP trisodium was evaluated by powder X-ray diffraction, optical microscopy, thermal analysis and IR spectroscopy. In addition, various spectroscopic techniques and physicochemical measurements were used for characterisation of MnDPDP trisodium. Results: The crystallographic data obtained for MnDPDP trisodium show that the general core structure of the MnDPDP anion is similar to that seen in related substances. The metal coordination geometry is a distorted octahedron defined by 2 phenolate oxygens, 2 carboxylate oxygens and 2 amine nitrogens. The unit cell contains 2 MnDPDP anions, 6 sodium ions and 50 water molecules. The various spectroscopic data are consistent with the structure determined by X-ray crystallography. The product (Teslascan) has low viscosity, is isotonic with blood and has a physiological pH. Conclusion: MnDPDP trisodium is a crystalline, hygroscopic solid which is readily soluble in water. No evidence of polymorphism was seen in the samples studied.

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Chavan, Jotiram K., and Raju M. Patil. "Microwave assisted Synthesis and Characterization of Novel Acylhydrazoneoximes." Research Journal of Chemistry and Environment 27, no. 12 (November 5, 2023): 31–34. http://dx.doi.org/10.25303/2712rjce031034.

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The present study deals with microwave assisted synthesis of novel acylhydrazoneoximes using para-substituted isonitrosoacetophenones and terephthalohydrazide. The compounds have been characterized by physicochemical and spectroscopic techniques. TheUV-Visible spectroscopy has been used for electronic excitation to characterize each of these new acylhydrazoneoximes. FTIR spectroscopy is used to conduct the functional group study. 1H and 13C-NMR spectroscopy, mass spectrometry has also been used.

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Alrooqi, Arwa, Zahra M. Al-Amshany, Laila M. Al-Harbi, Tariq A. Altalhi, Moamen S. Refat, Ali M. Hassanien, Gaber A. M. Mersal, and Ahmed A. Atta. "Spectroscopic and Physicochemical Studies on 1,2,4-Triazine Derivative." Coatings 12, no. 5 (May 23, 2022): 714. http://dx.doi.org/10.3390/coatings12050714.

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A novel 5-(5-Bromo-2-hydroxybenzylidene)-6-oxo-3-phenyl-5,6-dihydro-1,2,4-triazine-2(1H)-carbothioamide (4) “compound 4” was synthesized. The chemical structure of compound 4 was confirmed with spectroscopic techniques. Thermal analysis (TGA/dTGA) studies were conducted for identifying the kinetic thermodynamic parameters and the thermal stability of the synthesized compound 4. Cyclic voltammetric studies were performed for recognizing electrochemical characteristics of the synthesized compound 4. The calculated highest occupied molecular orbital (HOMO), lowest unoccupied molecular orbital (LUMO), and the band gap were found to be −3.61, −5.32, and 1.97 eV, respectively. Using a diffused reflectance spectroscopy (DRS) technique, the estimated values of the optical band transitions of compound 4 in powder form were found to be 2.07 and 2.67 eV. The structural properties of thermally evaporated compound 4 thin films were analyzed using field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), and Fourier transform infrared (FTIR) spectroscopy. It was found that compound 4 has a triclinic crystal structure. The optical transitions and the optical dispersion factors of compound 4 thin films were investigated using a UV-Vis spectroscopy technique. From the UV-Vis spectroscopy technique, Egind=3.6 V was estimated for both the as-deposited and annealed thin films. For the as-deposited film, there were two photoluminescence (PL) emission peaks centered at 473 and 490 nm with a shoulder at 422 nm. For the annealed film at 423 K, there were five PL emission peaks centered at 274, 416, 439, 464, and 707 nm with a shoulder at 548 nm. The dark electrical conduction of compound 4 thin film was through a thermally activated process with activation energy equaling 0.88 eV.

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Irgi, Evgenia P., George D. Geromichalos, Sofia Balala, Jakob Kljun, Stavros Kalogiannis, Athanasios Papadopoulos, Iztok Turel, and George Psomas. "Cobalt(ii) complexes with the quinolone antimicrobial drug oxolinic acid: structure and biological perspectives." RSC Advances 5, no. 46 (2015): 36353–67. http://dx.doi.org/10.1039/c5ra05308k.

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Inoue, Hidenari. "SPECTROSCOPIC AND PHYSICOCHEMICAL METHODS FOR STUDYING THE INTERACTION OF METALLOPORPHYRIN WITH DNA." Indonesian Journal of Chemistry 2, no. 3 (June 9, 2010): 131–34. http://dx.doi.org/10.22146/ijc.21907.

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In recent years studies on the interaction of porphyrin with DNA have received much attention because of the importance in DNA-probing and photodynamic therapy of cancer. A variety of spectroscopic methods, e.g. NMR, ESR, Mössbauer, UV-visible absorption, circular dichroism (CD), magnetic circular dichroism (MCD), IR and Raman spectroscopy, have been employed for studying interactions between porphyrin and DNA. Of these spectroscopic methods, only a few instrumental analytical techniques applicable to an aqueous buffer solution of DNA have been particularly developed to investigate porphyrin-DNA interactions. On the other hand, a number of physicochemical methods, e.g. gel electrophoresis, melting temperature measurements and hydrodynamic methods such as viscosity and sedimentation measurements, have been also used for determining the binding modes of porphyrin to DNA. The present lecture will focus on the application of visible absorption, CD and MCD spectroscopy as well as melting temperature and viscosity measurements to studies of porphyrin-DNA interactions.

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Gieroba, Barbara, Grzegorz Kalisz, Mikolaj Krysa, Maryna Khalavka, and Agata Przekora. "Application of Vibrational Spectroscopic Techniques in the Study of the Natural Polysaccharides and Their Cross-Linking Process." International Journal of Molecular Sciences 24, no. 3 (January 30, 2023): 2630. http://dx.doi.org/10.3390/ijms24032630.

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Polysaccharides are one of the most abundant natural polymers and their molecular structure influences many crucial characteristics—inter alia hydrophobicity, mechanical, and physicochemical properties. Vibrational spectroscopic techniques, such as infrared (IR) and Raman spectroscopies are excellent tools to study their arrangement during polymerization and cross-linking processes. This review paper summarizes the application of the above-mentioned analytical methods to track the structure of natural polysaccharides, such as cellulose, hemicellulose, glucan, starch, chitosan, dextran, and their derivatives, which affects their industrial and medical use.

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Banipal, Tarlok Singh, Amandeep Kaur, Imran Ahmd Khan, and Parampaul Kaur Banipal. "Exploring the thermodynamics and conformational aspects of nicotinic acid binding with bovine serum albumin: a detailed calorimetric, spectroscopic and molecular docking study." RSC Advances 6, no. 41 (2016): 34754–69. http://dx.doi.org/10.1039/c5ra28028a.

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An attempt to obtain a physicochemical and conformational outlook on the binding interaction of vitamin B₃ (NA) with a model transport protein BSA using calorimetry, light scattering, molecular docking, and spectroscopic techniques.

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Segers, Karen, Sven Declerck, Debby Mangelings, Yvan Vander Heyden, and Ann Van Eeckhaut. "Analytical techniques for metabolomic studies: a review." Bioanalysis 11, no. 24 (December 2019): 2297–318. http://dx.doi.org/10.4155/bio-2019-0014.

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Metabolomics is the comprehensive study of small-molecule metabolites. Obtaining a wide coverage of the metabolome is challenging because of the broad range of physicochemical properties of the small molecules. To study the compounds of interest spectroscopic (NMR), spectrometric (MS) and separation techniques (LC, GC, supercritical fluid chromatography, CE) are used. The choice for a given technique is influenced by the sample matrix, the concentration and properties of the metabolites, and the amount of sample. This review discusses the most commonly used analytical techniques for metabolomic studies, including their advantages, drawbacks and some applications.

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Singha, Uttam Kumar, Sudarshan Pradhan, Dipu Kumar Mishra, Pritika Gurung, Anmol Chettri, and Biswajit Sinha. "Synthesis, physicochemical characterisation and DNA binding study of a novel azo Schiff base Ni(II) complex." European Journal of Chemistry 14, no. 2 (June 30, 2023): 280–86. http://dx.doi.org/10.5155/eurjchem.14.2.280-286.2375.

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The azo Schiff base ligand was synthesised, along with its Ni(II) complex, by diazotisation of salicylaldehyde with 4-nitroaniline in accordance with the accepted literature approach. Using a variety of spectroscopic techniques, the resulting complex is analysed both quantitatively and qualitatively (Elemental analysis, FT-IR spectroscopy, UV-VIS spectroscopy, 1H NMR, etc.). Spectral measurements of the complex revealed a mole ratio of 1:1. The non-electrolytic nature of the complex is confirmed by molar conductance investigation. The unique azo compound had a tetrahedral shape as a result of the tetra coordination of two phenolic oxygen and two imine nitrogen. The ability of the metal complexes to bind DNA was examined using absorption spectroscopy, fluorescence spectroscopy, viscosity tests, and thermal denaturation methods. Experimental research suggests that complexes bind to DNA through intercalation.

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Mac, Hoa Xuan, Thanh Tung Pham, Nga Thi Thanh Ha, Lien Le Phuong Nguyen, László Baranyai, and László Friedrich. "Current Techniques for Fruit Juice and Wine Adulterant Detection and Authentication." Beverages 9, no. 4 (October 9, 2023): 84. http://dx.doi.org/10.3390/beverages9040084.

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Fruit juice and wine are important beverages that are consumed all over the world. Due to their constantly increasing demand and high value, fruit juice and wine are one of the most frequent targets of adulteration. Since adulterated foods are proven to have harmful effects on health, several approaches have been utilized for the detection of fruit juice and wine adulteration. Based on the requirement for sample destruction, analytical techniques to assess food authenticity can be classified into 2 main categories, i.e., destructive and non-destructive techniques. This paper provides an overview on the principle of adulteration detection, its application and performance, and the advantages and limitations of various analytical techniques. Destructive approaches, such as physicochemical methods, isotope analysis, elemental analysis, chromatographic techniques, and DNA-based techniques, are reviewed. Furthermore, non-destructive approaches, including spectroscopic-based techniques, nuclear magnetic resonance spectroscopic technique, electronic techniques, and imaging-based techniques, are discussed.

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Bhatti, Manisha, Jitender Singh, and Divya Dhawal Bhandari. "Compendium of P. Scrobiculatum: Phytochemical, Physicochemical, Antioxidant, Antiulcer, and Spectroscopic Analysis." Biomedical and Pharmacology Journal 16, no. 2 (June 30, 2023): 885–97. http://dx.doi.org/10.13005/bpj/2671.

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Background: Paspalum Scrobiculatum (Kodomillet) plant is found in various regions of India and possesses several pharmacological activities such as nutritive, anti-fungal, anti-diabetic, etc. The researchers are more focused these days on exploring other potential activities of this plant and the constituents present. Methods: Present study emphasized preliminary analysis such as macroscopic study, phytochemical analysis, Physicochemical investigation, determination of ash content, (Total flavonoid content), antioxidant property and characterization of extracted components with different spectral techniques and antiulcer potential. later, this study will be helpful in the determination of its medicinal importance in Pharmacy. Results: In macroscopic analysis, it was studied that paspalum scrobiculatum seeds are light brown to dark brown colored, round to oval shaped grain having a size approximately 4mm. Further, the seeds were analyzed for determination of the extractive values and found to be 2.82 % w/w, 0.79 %w/w, 4.26 % w/w 2.40 % w/w in pet. ether, chloroform, ethanol, and water extracts respectively, and extractive value was found highest in ethanol extract. Furthermore, phytochemical analysis of all the different extracts revealed the presence of phenolic components, flavonoids amino acids, protein, and carbohydrates in ethanolic extract, whereas in aqueous extract there was the presence of saponins and carbohydrates. Then, spectral characterization analysis was done with Infrared spectroscopy, Nuclear magnetic resonance, and Mass spectroscopy techniques and revealed the presence of different active metabolites in the ethanolic extract which may be considered for numerous pharmacological properties, thus further processed for anti-ulcer potential. The ethanolic extract has given promising results as an antiulcer agent against the standard drug omeprazole. The present research concluded from various parameters such as macroscopic evaluation, successive extraction, physicochemical investigation, phytochemical investigation, and spectral analysis that ethanolic extract of plant P. Scrobiculatum contains the maximum amount of secondary metabolites and was further investigated for anti-ulcer potential at a dose of 250 mg/kg and 500 mg/kg and the % Ulcer protection was found to be 26.81% and 49.24 % respectively against the standard drug omeprazole.

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Godzo, Hrisanta, Olga Gigopulu, Nikola Geskovski, Jelena Acevska, Natalija Nakov, Jasmina Tonic-Ribarska, Ana Poceva-Panovska, and Katerina Brezovska. "PLS based quantitative determination of insulin aspart in solution using Raman spectroscopy." Arhiv za farmaciju 74, no. 2 (2024): 206–15. http://dx.doi.org/10.5937/arhfarm74-49901.

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The complex structure of medicines containing polypeptide active substances requires the implementation of challenging analytical approaches, based on physicochemical methods, and, where necessary, biological assays for quality control, as well as for the detection of substandard and falsified products. Vibrational spectroscopic techniques, including Raman spectroscopy, are fast, powerful, and non-destructive techniques which, when combined with multivariate chemometric modelling, can provide specific identification, quantitative determination, and insight into the secondary structure of proteins and peptides. The aim of this study was to investigate the possibility of using Raman spectroscopy as a screening method for quantification of pharmaceutical products containing active substances with polypeptide structures. For that purpose, a model based on partial least square (PLS) analysis for quantitative determination of insulin aspart in solution was developed using Raman spectroscopy. The proposed model enables the establishment of a rapid approach for screening of the quality of formulations containing active substances with polypeptide structure, providing the selection of suspected samples that should be further analysed using routine techniques, which are time-consuming and costly.

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Gieroba, Barbara, Anna Sroka-Bartnicka, Paulina Kazimierczak, Grzegorz Kalisz, Izabela S. Pieta, Robert Nowakowski, Marcin Pisarek, and Agata Przekora. "Effect of Gelation Temperature on the Molecular Structure and Physicochemical Properties of the Curdlan Matrix: Spectroscopic and Microscopic Analyses." International Journal of Molecular Sciences 21, no. 17 (August 26, 2020): 6154. http://dx.doi.org/10.3390/ijms21176154.

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In order to determine the effect of different gelation temperatures (80 °C and 90 °C) on the structural arrangements in 1,3-β-d-glucan (curdlan) matrices, spectroscopic and microscopic approaches were chosen. Attenuated total reflection Fourier transform infrared spectroscopy (ATR FT-IR) and Raman spectroscopy are well-established techniques that enable the identification of functional groups in organic molecules based on their vibration modes. X-ray photoelectron spectroscopy (XPS) is a quantitative analytical method utilized in the surface study, which provided information about the elemental and chemical composition with high surface sensitivity. Contact angle goniometer was applied to evaluate surface wettability and surface free energy of the matrices. In turn, the surface topography characterization was obtained with the use of atomic force microscopy (AFM) and scanning electron microscopy (SEM). Described techniques may facilitate the optimization, modification, and design of manufacturing processes (such as the temperature of gelation in the case of the studied 1,3-β-d-glucan) of the organic polysaccharide matrices so as to obtain biomaterials with desired characteristics and wide range of biomedical applications, e.g., entrapment of drugs or production of biomaterials for tissue regeneration. This study shows that the 1,3-β-d-glucan polymer sample gelled at 80 °C has a distinctly different structure than the matrix gelled at 90 °C.

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Martín, Andrés Pérez-San, Frutos C. Marhuenda-Egea, Maria Angeles Bustamante, and Gustavo Curaqueo. "Spectroscopy Techniques for Monitoring the Composting Process: A Review." Agronomy 13, no. 9 (August 27, 2023): 2245. http://dx.doi.org/10.3390/agronomy13092245.

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Composting is described as a sustainable alternative to organic waste reuse from the agricultural and household sectors. The organic matter degradation and stabilization product presents great variability due to the waste composition used. Thus, the use of techniques that allow the monitoring of the decomposition process is necessary to determine the quality of the final product. Therefore, this review critically analyzes and updates the chemical spectroscopy methods described for the evaluation of the organic matter transformation in the composting process to optimize and generate amendments for agricultural use. This review examines spectroscopic techniques such as ultraviolet-visible (UV-Vis), infrared (IR), fluorescence, and 13C NMR reported for the evolution and maturation of carbonate structures in composting. In addition, they are used in the study of indicators for monitoring the degradation of complex structures, such as sugars and proteins, for the formation of precursors that are responsible for the formation of highly stabilized substances such as humic and fulvic compounds. Finally, these parameters may be used to elucidate organic matter degradation and its stabilization process, establish patterns that characterize each stage of composting along with its physicochemical characteristics, and monitor potential phytotoxicity levels.

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Haroun, Mahdi, Azni Idris, and Syed Omar. "Analysis of heavy metals during composting of the tannery sludge using physicochemical and spectroscopic techniques." Journal of Hazardous Materials 165, no. 1-3 (June 15, 2009): 111–19. http://dx.doi.org/10.1016/j.jhazmat.2008.09.092.

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Udrescu, Lucreţia, Laura Sbârcea, Adriana Fuliaş, Ionuţ Ledeţi, Titus Vlase, Paul Barvinschi, and Ludovic Kurunczi. "Physicochemical characterization of zofenopril inclusion complex with hydroxypropyl-β-cyclodextrin." Journal of the Serbian Chemical Society 80, no. 4 (2015): 485–97. http://dx.doi.org/10.2298/jsc140828118u.

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Zofenopril calcium (ZOF)is one of the newest angiotensin converting enzyme (ACE) inhibitor, is one of the highly lipophilic newest angiotensin and with low water solubility. This research investigates the interaction between ZOF and a ?-cyclodextrin chemically modified derivative, 2-hydroxypropyl-?-cyclodextrin (HPBCD), in order to prove the formation of an inclusion complex with an enhanced water solubility profile of ZOF. In this research is reported for the first time the physicochemical characterization and the solubility profile of an inclusion complex between ZOF and HPBCD. Different spectroscopic techniques (UV absorption spectrometry, powder X-ray diffraction, attenuated total reflectance Fourier transform IR spectroscopy) were applied in order to prove the formation of the ZOF/HPBCD inclusion complex, both in water and in solid state, backed by thermal analysis (TGA/DTG/HF). The obtained results confirm that the physicochemical properties of the ZOF/HPBCD binary system, prepared using the kneading method, are different in comparison both with the parent substances and the corresponding physical mixture, thus suggesting that an inclusion complex was formed. After the formation of the inclusion complex with HPBCD, the solubility test indicated that the water solubility of ZOF was increased by 5 times.

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Caamal-Fuentes, Edgar, Daniel Robledo, and Yolanda Freile-Pelegrín. "Physicochemical Characterization and Biological activities of Sulfated Polysaccharides from Cultivated Solieria filiformis Rhodophyta." Natural Product Communications 12, no. 6 (June 2017): 1934578X1701200. http://dx.doi.org/10.1177/1934578x1701200601.

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Crude and alkali treated carrageenan from the cultivated marine alga Solieria filiformis (Rhodophyta) were obtained, characterized and evaluated for their cytotoxic and antiprotozoal activities. Yields, molecular weights and chemical composition of carrageenans were determined. Their structures were elucidated through spectroscopic techniques including FT-IR and CP-MAS 13C NMR spectra. Crude and alkali treated carrageenan seems to be chemically similar to the iota-family carrageenan. Crude carrageenan showed antiprotozoal activity against Giardia intestinalis.

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Naglah, Ahmed M., Mohamed A. Al-Omar, Abdulrahman A. Almehizia, Ahmad J. Obaidullah, Mashooq A. Bhat, Nasser S. Al-Shakliah, Kaouther Belgacem, Badriah M. Majrashi, Moamen S. Refat, and Abdel Majid A. Adam. "Synthesis, Spectroscopic, and Antimicrobial Study of Binary and Ternary Ruthenium(III) Complexes of Ofloxacin Drug and Amino Acids as Secondary Ligands." Crystals 10, no. 3 (March 20, 2020): 225. http://dx.doi.org/10.3390/cryst10030225.

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This article aimed to synthesis, spectroscopic, physicochemical characterizations, and catalytic studies on some ofloxacin (OFL) complexes with ruthenium(III) [Ru(III)] metal ions. The Ru(III)-OFL complex, [Ru(OFL)2(Cl)2]Cl and two mixed-ligand complexes, [Ru(OFL)(AA)(H2O)2]Cl2 derived from OFL as the primary ligand and amino acids [AA; either glycine (Gly) or alanine (Ala)] as the secondary ligands, were synthesized and characterized using microanalytical, spectroscopic, and physical techniques including element composition, molar conductivity, infrared, electronic spectra, thermal, X-ray powder diffraction (XRD), Energy dispersive X-ray spectroscopy (EDX), Scanning electron microscopy (SEM), and Transmittance electron microscopy (TEM) analyses. The element analysis data describe the formation of 1:2 [Ru(III):OFL] and 1:1:1 [Ru(III):OFL:AA] complexes. The octahedral geometry of the complexes was confirmed by their magnetic moment and diffused reflectance. Fourier Transform Infrared spectroscopic (FTIR) measurements suggested that the ligands chelated with Ru(III) ions through the nitrogen atoms of the piperazine ring. In vitro antibacterial efficiency of the OFL compounds was evaluated by paper disc diffusion method. Significant antimicrobial activities were observed for some compounds of the series.

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Algarra, Manuel, Ana L. Cuevas, Ma Valle Martínez de Yuso, Rocío Romero, Beatriz Alonso, Carmen M. Casado, and Juana Benavente. "Optical and Physicochemical Characterizations of a Cellulosic/CdSe-QDs@S-DAB5 Film." Nanomaterials 12, no. 3 (January 29, 2022): 484. http://dx.doi.org/10.3390/nano12030484.

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CdSe quantum dots nanoparticles were coated with the thiolated (DiAminoButane based dendrimer) DAB dendrimer of fifth generation (S-DAB5) and embedded in a highly hydrophilic regenerated cellulose (RC) film by simple dip-coating method (immersion in QD-dendrimer aqueous solution) as a way to get a flexible nano-engineered film (RC-4/CdSe-QDs@S-DAB5) with high transparency and photoluminescence properties for different applications. Optical changes in the RC film associated with QDs inclusion were determined by spectroscopic ellipsometry (SE) measurements, which provide information on changes caused in the refraction index and the extinction coefficients of the film, as well as by light transmittance/reflectance curves and photoluminescence (PL) spectra. Impedance spectroscopy (IS) and other typical physicochemical techniques for material characterization (TEM, SEM and XPS) have also been used in order to have more complete information on film characteristics. A comparison of RC-4/CdSe-QDs@S-DAB5 film optical characteristics with those exhibited by other RC-modified films depending on the type of dendrimer was also carried out.

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Kostelidou, Alexandra, Franc Perdih, Jakob Kljun, Foteini Dimou, Stavros Kalogiannis, Iztok Turel, and George Psomas. "Metal(II) Complexes of the Fluoroquinolone Fleroxacin: Synthesis, Characterization and Biological Profile." Pharmaceutics 14, no. 5 (April 20, 2022): 898. http://dx.doi.org/10.3390/pharmaceutics14050898.

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A series of complexes of divalent transition metals (Cu(II), Mn(II), Zn(II), Co(II) and Ni(II)) with the quinolone antibacterial agent fleroxacin, in the absence or presence of an α-diimine such as 2,2′-bipyridine, 1,10-phenanthroline or 2,2′-bipyridylamine, were prepared and characterized. The complexes were characterized by various physicochemical and spectroscopic techniques and by single-crystal X-ray crystallography. The in vitro antibacterial activity of the complexes was studied against the bacterial strains Staphylococcus aureus, Bacillus subtilis and Xanthomonas campestris and was higher than that of free quinolone. The affinity of the complexes for bovine and human serum albumin was studied by fluorescence emission spectroscopy and the determined binding constants showed tight and reversible binding to the albumins. The interaction of the complexes with calf-thymus DNA was studied by various techniques, which showed that intercalation was the most plausible mode of interaction.

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Hassoun, Abdo, Maria Carpena, Miguel A. Prieto, Jesus Simal-Gandara, Fatih Özogul, Yeşim Özogul, Özlem Emir Çoban, et al. "Use of Spectroscopic Techniques to Monitor Changes in Food Quality during Application of Natural Preservatives: A Review." Antioxidants 9, no. 9 (September 17, 2020): 882. http://dx.doi.org/10.3390/antiox9090882.

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Consumer demand for food of high quality has driven research for alternative methods of food preservation on the one hand, and the development of new and rapid quality assessment techniques on the other hand. Recently, there has been a growing need and interest in healthier food products, which has led to an increased interest in natural preservatives, such as essential oils, plant extracts, and edible films and coatings. Several studies have shown the potential of using biopreservation, natural antimicrobials, and antioxidant agents in place of other processing and preservation techniques (e.g., thermal and non-thermal treatments, freezing, or synthetic chemicals). Changes in food quality induced by the application of natural preservatives have been commonly evaluated using a range of traditional methods, including microbiology, sensory, and physicochemical measurements. Several spectroscopic techniques have been proposed as promising alternatives to the traditional time-consuming and destructive methods. This review will provide an overview of recent studies and highlight the potential of spectroscopic techniques to evaluate quality changes in food products following the application of natural preservatives.

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Muniyappan, Srinivasan, Yuxi Lin, Young-Ho Lee, and Jin Hae Kim. "17O NMR Spectroscopy: A Novel Probe for Characterizing Protein Structure and Folding." Biology 10, no. 6 (May 21, 2021): 453. http://dx.doi.org/10.3390/biology10060453.

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Oxygen is a key atom that maintains biomolecular structures, regulates various physiological processes, and mediates various biomolecular interactions. Oxygen-17 (17O), therefore, has been proposed as a useful probe that can provide detailed information about various physicochemical features of proteins. This is attributed to the facts that (1) 17O is an active isotope for nuclear magnetic resonance (NMR) spectroscopic approaches; (2) NMR spectroscopy is one of the most suitable tools for characterizing the structural and dynamical features of biomolecules under native-like conditions; and (3) oxygen atoms are frequently involved in essential hydrogen bonds for the structural and functional integrity of proteins or related biomolecules. Although 17O NMR spectroscopic investigations of biomolecules have been considerably hampered due to low natural abundance and the quadruple characteristics of the 17O nucleus, recent theoretical and technical developments have revolutionized this methodology to be optimally poised as a unique and widely applicable tool for determining protein structure and dynamics. In this review, we recapitulate recent developments in 17O NMR spectroscopy to characterize protein structure and folding. In addition, we discuss the highly promising advantages of this methodology over other techniques and explain why further technical and experimental advancements are highly desired.

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Grieser, Franz, and Calum J. Drummond. "The physicochemical properties of self-assembled surfactant aggregates as determined by some molecular spectroscopic probe techniques." Journal of Physical Chemistry 92, no. 20 (October 1988): 5580–93. http://dx.doi.org/10.1021/j100331a012.

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Jana, Snehasis. "Physicochemical, Thermal and Spectroscopic Characterization of the Energy of Consciousness Healing Treated Withania somnifera (Ashwagandha) Root Extract." Journal of Natural & Ayurvedic Medicine 5, no. 1 (2021): 1–10. http://dx.doi.org/10.23880/jonam-16000296.

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Ashwagandha root extract is widely used in nutraceutical preparations due to its broad range of pharmacological activities. The objective of this study was to analyse the impact of Biofield Energy Treatment (The Trivedi Effect ® ) on the physico- chemical, thermal and spectral properties of ashwagandha root extract by using various analytical techniques. The sample of ashwagandha root extract was divided into two parts in which one part was kept untreated and called as control sample; while the other part was provided with the Consciousness Energy Healing Treatment remotely by the Biofield Energy Healer, Mr. Mahendra Kumar Trivedi and termed as Biofield Energy Treated sample. The study reported that the particle size values at d 10 , d 50 , d 90 , and D (4,3) in the Biofield Energy Treated sample was significantly decreased by 9.23%, 9.04%, 11.86%, and 10.59%, respectively compared with the control sample. Thus, the surface area of the treated sample was significantly increased by 10.75% compared to the control sample. The PXRD analysis showed that the control as well as the Biofield Energy Treated samples was amorphous in nature. The DSC analysis showed that the onset evaporation temperature and latent heat of vaporization were significantly altered by 2.18% and-10.29%, respectively in the Biofield Energy Treated sample compared with the control sample. The TGA analysis indicated the four step thermal degradation of both the samples. The 1 st , 2 nd , 3 rd , and 4 th steps of thermal degradation of the treated sample showed an alteration in the weight loss by -6.59%, 1.97%, -1.80%, and -8.65%, respectively along with 0.81% reduction in the total weight loss, compared with the control sample. Besides, the maximum thermal degradation temperature (T max ) in the control sample was observed at 234.17°C and 365.12°C for the two broad peaks, which was decreased by 1.73% and 0.82%, respectively compared to the control sample. The overall analysis suggests that the Energy of Consciousness Healing Treatment might enhance the solubility, absorption, and bioavailability profile of ashwagandha root extract along with altered thermal stability. Such altered properties might help in designing better pharmaceutical and nutraceutical preparations; thereby provide better therapeutic response against various diseases such as amnesia, arthritis, anxiety, cancer, impotence, neurodegenerative, and cardiovascular diseases.

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Vázquez-Nambo, Manuel, José-Antonio Gutiérrez-Gnecchi, Enrique Reyes-Archundia, Wuqiang Yang, Marco-A. Rodriguez-Frias, Juan-Carlos Olivares-Rojas, and Daniel Lorias-Espinoza. "Experimental Study of Electrical Properties of Pharmaceutical Materials by Electrical Impedance Spectroscopy." Applied Sciences 10, no. 18 (September 21, 2020): 6576. http://dx.doi.org/10.3390/app10186576.

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The physicochemical characterization of pharmaceutical materials is essential for drug discovery, development and evaluation, and for understanding and predicting their interaction with physiological systems. Amongst many measurement techniques for spectroscopic characterization of pharmaceutical materials, Electrical Impedance Spectroscopy (EIS) is powerful as it can be used to model the electrical properties of pure substances and compounds in correlation with specific chemical composition. In particular, the accurate measurement of specific properties of drugs is important for evaluating physiological interaction. The electrochemical modelling of compounds is usually carried out using spectral impedance data over a wide frequency range, to fit a predetermined model of an equivalent electrochemical cell. This paper presents experimental results by EIS analysis of four drug formulations (trimethoprim/sulfamethoxazole C14H18N4O3-C10H11N3O3, ambroxol C13H18Br2N2O.HCl, metamizole sodium C13H16N3NaO4S, and ranitidine C13H22N4O3S.HCl). A wide frequency range from 20 Hz to 30 MHz is used to evaluate system identification techniques using EIS data and to obtain process models. The results suggest that arrays of linear R-C models derived using system identification techniques in the frequency domain can be used to identify different compounds.

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J. Kumar, P. Kumar, S. Kumar, R. Langyan, and R. Kumar. "TEMPLATE DIRECTED SYNTHESIS AND CHARACTERIZATION OF MACROCYCLIC COMPLEXES: In-silico DOCKING AND ANTIMICROBIAL STUDIES." Rasayan Journal of Chemistry 14, no. 04 (2021): 2567–76. http://dx.doi.org/10.31788/rjc.2021.1446465.

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A new series of macrocyclic complexes have been synthesized by template condensation between 3,4- diaminotoluene and acetylacetone in the presence of trivalent metal ions to form macrocyclic complexes having four coordination sites. Different spectroscopic and physicochemical techniques were used to establish the geometry and structural framework of the synthesized macrocyclic complexes. Further, these complexes were also investigated for their antibacterial, antifungal and antioxidant activities. Removal of methylene blue dye from the aqueous by iron complexes was also investigated.

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J. Kumar, P. Kumar, S. Kumar, R. Langyan, and R. Kumar. "TEMPLATE DIRECTED SYNTHESIS AND CHARACTERIZATION OF MACROCYCLIC COMPLEXES: In-silico DOCKING AND ANTIMICROBIAL STUDIES." Rasayan Journal of Chemistry 14, no. 04 (2021): 2567–76. http://dx.doi.org/10.31788/rjc.2021.1446465.

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A new series of macrocyclic complexes have been synthesized by template condensation between 3,4- diaminotoluene and acetylacetone in the presence of trivalent metal ions to form macrocyclic complexes having four coordination sites. Different spectroscopic and physicochemical techniques were used to establish the geometry and structural framework of the synthesized macrocyclic complexes. Further, these complexes were also investigated for their antibacterial, antifungal and antioxidant activities. Removal of methylene blue dye from the aqueous by iron complexes was also investigated.

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Salvador, Lorena, Michelle Guijarro, Daniela Rubio, Bolívar Aucatoma, Tanya Guillén, Paul Vargas Jentzsch, Valerian Ciobotă, et al. "Exploratory Monitoring of the Quality and Authenticity of Commercial Honey in Ecuador." Foods 8, no. 3 (March 20, 2019): 105. http://dx.doi.org/10.3390/foods8030105.

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Honey is one of the oldest sweetening foods and has economic importance, making this product attractive to adulteration with cheap sugars. This can cause a critical problem in the honey industry and a possible health risk. The present work has the aim of evaluating the authenticity of honey commercialized in two different provinces of Ecuador (Pichincha and Loja) by performing physicochemical and spectroscopic analyses. For this study 25 samples were collected from different places and markets and characterized by water, sucrose, reducing sugars and electric conductivity measurement. Also, their Raman and Infrared (IR) spectra were recorded and analysed using a Principal Component Analysis (PCA) in order to verify the quality of the honeys. In addition, a screening of several pesticides was performed in order to verify possible chemical threats to human health and honey bees. It was found that 8 samples have a deviation from the Standard established parameters. Two of them have a high difference in the content of sucrose and reducing sugars, which are located deviated from all the other samples in the PCA of the applied vibrational spectroscopy (IR/Raman), shaping two clear clusters. The results show that Raman and IR spectroscopy is appropriate techniques for the quality control of honey and correlates well with the physicochemical analyses.

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Marques, Ana, Paulo Costa, Sérgia Velho, and Maria Amaral. "Analytical Techniques for Characterizing Tumor-Targeted Antibody-Functionalized Nanoparticles." Life 14, no. 4 (April 10, 2024): 489. http://dx.doi.org/10.3390/life14040489.

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The specific interaction between cell surface receptors and corresponding antibodies has driven opportunities for developing targeted cancer therapies using nanoparticle systems. It is challenging to design and develop such targeted nanomedicines using antibody ligands, as the final nanoconjugate’s specificity hinges on the cohesive functioning of its components. The multicomponent nature of antibody-conjugated nanoparticles also complicates the characterization process. Regardless of the type of nanoparticle, it is essential to perform physicochemical characterization to establish a solid foundation of knowledge and develop suitable preclinical studies. A meaningful physicochemical evaluation of antibody-conjugated nanoparticles should include determining the quantity and orientation of the antibodies, confirming the antibodies’ integrity following attachment, and assessing the immunoreactivity of the obtained nanoconjugates. In this review, the authors describe the various techniques (electrophoresis, spectroscopy, colorimetric assays, immunoassays, etc.) used to analyze the physicochemical properties of nanoparticles functionalized with antibodies and discuss the main results.

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Hada, Alexandru-Milentie, Nina Burduja, Marco Abbate, Claudio Stagno, Guy Caljon, Louis Maes, Nicola Micale, et al. "Supramolecular assembly of pentamidine and polymeric cyclodextrin bimetallic core–shell nanoarchitectures." Beilstein Journal of Nanotechnology 13 (November 18, 2022): 1361–69. http://dx.doi.org/10.3762/bjnano.13.112.

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Advanced nanoscale antimicrobials, originated from the combination of noble metal nanoparticles (NPs) with conventional antimicrobial drugs, are considered the next generation of antimicrobial agents. Therefore, there is an increasing demand for rapid, eco-friendly, and relatively inexpensive synthetic approaches for the preparation of nontoxic metallic nanostructures endowed with unique physicochemical properties. Recently, we have proposed a straightforward synthetic strategy that exploits the properties of polymeric β-cyclodextrin (PolyCD) to act as both the reducing and stabilizing agent to produce monodispersed and stable gold-based NPs either as monometallic (nanoG) structures or core–shell bimetallic (nanoGS) architectures with an external silver layer. Here, we describe the preparation of a supramolecular assembly between nanoGS and pentamidine, an antileishmanial drug endowed with a wide range of therapeutic properties (i.e., antimicrobial, anti-inflammatory, and anticancer). The physicochemical characterization of the supramolecular assembly (nanoGSP) in terms of size and colloidal stability was investigated by complementary spectroscopic techniques, such as UV–vis, ζ-potential, and dynamic light scattering (DLS). Furthermore, the role of PolyCD during the reduction/stabilization of metal NPs was investigated for the first time by NMR spectroscopy.

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Saraswat, Nikita, Neetu Sachan, and Phool Chandra. "Standardization Using Analytical Techniques (UV, NMR, FTIR, HPLC, Mass) and Pharmacognostic Evaluation of the Roots of Selinum vaginatum: A Rare Himalayan Plant of the Rohtang Region." Current Biotechnology 9, no. 2 (November 16, 2020): 89–103. http://dx.doi.org/10.2174/2211550109666200303111411.

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Introduction: Selinum vaginatum is an endemic Indian plant present on high altitude and is known as “Bhootkeshi,” by the locals. The root of plant Selinum vaginatum commonly known as “Bhootkeshi” from the family Umbellifercae is an aromatic herbal drug. Selinum vaginatum has been used traditionally for curing seizures, epilepsy, mental illness, and hysteria. This plant has shown therapeutic effects as used by the locals. There is no data available regarding standardization of the roots of Selinum vaginatum. It is a novel work as the plant is rarely found and shows medicinal values but no quality control work has been performed. Objective: The aim of this paper is to study quality control and carry out physicochemical analysis and standardization of the roots of Selinum vaginatum for determining its quality and purity. As no work has been performed on the roots of this plant, so standardization will help in keeping a record of the parameters exhibited during the evaluation of the roots of Selinum vaginatum. Methods: The organoleptic characteristics were studied and physicochemical tests, phytochemical analysis, fluorescence analysis, TLC, UV, FTIR, NMR, and Electrospray Ionisation - Mass spectroscopy, HPLC and other parameters were carried out for the standardization of the test drug. The procedures were carried out as per the WHO standards. The total ash values, swelling index, foaming index, moisture content, alcohol, and water-soluble extractive values were calculated. The TLC profile of Selinum vaginatum was observed and the UV, FTIR, HPLC, NMR and Mass spectroscopies of the plant were also performed. Results: The microscopic results showed the presence of schizogenous canals in abundance, cork cells, oil and globules, while medullary rays and pith were absent and around 10-17 layers of cells were seen. The presence of active compounds like phenols, terpenoids, alkaloids, coumarins, essential oils, tannins, saponins, carbohydrates, and acids was reported by phytochemical tests, TLC, UV, NMR, HPLC, Mass, and FTIR spectroscopy methods. These compounds can be studied in detail for understanding the potential pharmacological benefits and decoding the traditional uses. The spectroscopic analysis and physicochemical tests have shown the presence of phenols, esters, organic halogens, carbohydrate, carboxylic acids, alcohols, ethers, and glycosides which must be responsible for the medicinal properties of the plant. Conclusion: This study has provided a set of information that will be useful for the identification of fresh batches of the roots of Selinum vaginatum and this can be used as a reference set of information for accessing the purity, quality and identification, and analysis of the authenticity of the plant roots. Spectroscopic techniques have shown peaks, which on interpretation have reported the presence of active compounds - (coumarins like selenidin, angelicin, vaginidine, furocoumarin - oroselol and coumarin derivative- lomatin, isovaleric acid, Valeranone, Tricyclene, p-Cymene, α-Pinene, β-Pinene, Camphene, Borneol, p- Camphene, cholorgenic acid, β-Myrcene, Limonene and α-Pineneoxide which can be studied for understanding and identifying the pharmacological actions of the rhizomatous roots of S. vaginatum. All the information collected by research on the roots of S. vaginatum will help in the identification of crude drugs and also in the development of a standard for the drug Selinum vaginatum.

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Bala, Suman, Neha Sharma, Anu Kajal, and Sunil Kamboj. "Design, Synthesis, Characterization, and Computational Studies on Benzamide Substituted Mannich Bases as Novel, Potential Antibacterial Agents." Scientific World Journal 2014 (2014): 1–9. http://dx.doi.org/10.1155/2014/732141.

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A series of benzamide substituted Mannich bases(1–7)were synthesized. The synthesized derivatives were authenticated by TLC, UV-Visible, FTIR, NMR, and mass spectroscopic techniques and further screened forin vitroantibacterial activity by test tube dilution method using amoxicillin and cefixime as standard drugs. The compounds5,6, and7were found to be the most active antibacterial agents among all the synthesized compounds. The physicochemical similarity of the compounds with standard drugs was assessed by calculating various physicochemical properties using software programs. The percent similarity of synthesized compounds was found to be good and compound1was found to have higher percentage of similarity. The compounds were subjected to QSAR by multilinear regression using Analyze it version 3.0 software, and four statistically sound models were developed withR2(0.963–0.997),Radj2(0.529–0.982), andQ2(0.998–0.999) with goodF(2.35–65.56) values.

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33

Ahmed, Ayman H. "Zeolite-encapsulated transition metal chelates: synthesis and characterization." Reviews in Inorganic Chemistry 34, no. 3 (October 1, 2014): 153–75. http://dx.doi.org/10.1515/revic-2013-0013.

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AbstractThis article reviews some important recent works on the synthesis and characterization of zeolite-encapsulated transition metal complexes containing different organic ligands. Distinct methodologies of preparation, including the in situ one-pot template (IOPT) and flexible ligand methods (FLM) are described. The mode of bonding, composition, overall geometry and surface characteristics have been inferred by various physicochemical characterization techniques. Chemical analysis, spectroscopic methods [Fourier transform infrared spectroscopy (FT-IR), diffuse reflectance spectroscopy (DRS) and ultraviolet-visible (UV-Vis)], scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), energy-dispersive spectroscopy analysis of X-ray (EDAX), magnetic measurements, N2-adsorption-desorption and thermogravimetric studies have been proven to be powerful techniques to specify these host-guest nanocomposite materials (HGNM). In some cases, Mössbauer, photoluminescence and cyclic voltammetric data are informative. Recent results dealing with the immobilization of complexes concerning aza, heterocyclic, Schiff base and hydrazone ligands are presented. A comprehensive survey of the investigated materials manifested the successful incorporation of the complexes into the zeolite matrix, without collapsing the crystalline structure of zeolite. Occasionally, some of the encapsulated complexes showed structural properties and chemical behavior which are different from those of the neat complex owing to the zeolite constraints.

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Harkut, Neelam, and Padam N. Nagar. "Synthesis and Properties of N-Bromosuccinimide Derivatives of Ammonium Dialkyl/Alkylene Dithiophosphates." Bioinorganic Chemistry and Applications 2007 (2007): 1–6. http://dx.doi.org/10.1155/2007/24742.

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Reaction of N-bromosuccinimide with ammonium salt of alkylene (dialkyl) dithiophosphates, [OGOPS2NH4; G=–CMe2CMe2–CH2CMe2CH2–, CMe2CH2CHMe2–, CH2CH2CHMe2–; (RO)2PS2NH4; R=C2H5, n–C3H7, i–C3H7], in 1: 1 molor ratio in refluxing benzene solution yields red/brown-colored sticky liquids. These newly synthesized complexes have been characterised by physicochemical and spectroscopic techniques (MW, IR, NMR [H1andP31]). The computational semiempirical calculations (MOPAC6P/c) have also been studied for these complexes. On the basis of the above studies, the formation of P–S–N chemical linkage has been established.

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35

Trivedi, Mahendra Kumar, Neena Dixit, Parthasarathi Panda, Kalyan Kumar Sethi, and Snehasis Jana. "In-depth investigation on physicochemical and thermal properties of magnesium (II) gluconate using spectroscopic and thermoanalytical techniques." Journal of Pharmaceutical Analysis 7, no. 5 (October 2017): 332–37. http://dx.doi.org/10.1016/j.jpha.2017.03.006.

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36

Pratik, Panshu, and Prem Mohan Mishra. "Study of Isolation, Characterisation and Antimicrobial Activity of High Value Bioactive Compounds from Methanolic Extract of Leaves of Tilkor (Momordica Monadelpha)." Oriental Journal of Chemistry 34, no. 6 (December 17, 2018): 3145–52. http://dx.doi.org/10.13005/ojc/340662.

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In this paper an attempt has been made to highlight the physicochemical study of methnolic extract of leaves of Tilkor carried out by soxhlet extraction process, phytochemical analysis of the extract, separations, isolation of bioactive components through Thin Layer Chromatography (TLC) as well as column chromatography respectively and characterisation of isolated compound by the means of several spectral analysis such as 1H NMR, 13C NMR, IR, U.V. Mass spectroscopy. The methanolic extract of leaves of the plant (in tropical conditions of Mithilanchal, Bihar, India) reveal the presence of phytochemicals like alkaloids, flavanoids, tannins, saponins, cardiac glycosides, steroids, terpenoids etc. The secondary metaboilities showed antimicrobial activity. The two isolated compounds were characterised by spectroscopic techniques which revealed the structure of compound A as - stigmosterol and compound B as tritriaconatane and is also found to have antimicrobial activity.

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37

Kshirsagar, Prakash G., Valeria De Matteis, Sudipto Pal, and Shiv Shankar Sangaru. "Silver–Gold Alloy Nanoparticles (AgAu NPs): Photochemical Synthesis of Novel Biocompatible, Bimetallic Alloy Nanoparticles and Study of Their In Vitro Peroxidase Nanozyme Activity." Nanomaterials 13, no. 17 (September 1, 2023): 2471. http://dx.doi.org/10.3390/nano13172471.

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Facile synthesis of metal nanoparticles with controlled physicochemical properties using environment-friendly reagents can open new avenues in biomedical applications. Nanomaterials with controlled physicochemical properties have opened new prospects for a variety of applications. In the present study, we report a single-step photochemical synthesis of ~5 nm-sized silver (Ag) and gold (Au) nanoparticles (NPs), and Ag–Au alloy nanoparticles using L-tyrosine. The physicochemical and surface properties of both monometallic and bimetallic NPs were investigated by analytical, spectroscopic, and microscopic techniques. Our results also displayed an interaction between L-tyrosine and surface atoms that leads to the formation of AgAu NPs by preventing the growth and aggregation of the NPs. This method efficiently produced monodispersed NPs, with a narrow-sized distribution and good stability in an aqueous solution. The cytotoxicity assessment performed on breast cancer cell lines (MCF-7) revealed that the biofriendly L-tyrosine-capped AgNPs, AuNPs, and bimetallic AgAu NPs were biocompatible. Interestingly, AgAu NPs have also unveiled controlled cytotoxicity, cell viability, and in vitro peroxidase nanozyme activity reliant on metal composition and surface coating.

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Charczuk, Natalia, Nicole Nowak, and Rafal J. Wiglusz. "Synthesis and Investigation of Physicochemical Properties and Biocompatibility of Phosphate–Vanadate Hydroxyapatite Co-Doped with Tb3+ and Sr2+ Ions." Nanomaterials 13, no. 3 (January 23, 2023): 457. http://dx.doi.org/10.3390/nano13030457.

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Searching for biocompatible materials with proper luminescent properties is of fundamental importance, as they can be applied in fluorescent labeling and regenerative medicine. In this study, we obtained new phosphate–vanadate hydroxyapatites (abbr. HVps) co-doped with Sr2+ and Tb3+ ions via the hydrothermal method. We focused on examining the effect of various annealing temperatures (500, 600 and 700 °C) on the spectroscopic properties and morphology of the obtained HVps. To characterize their morphology, XRPD (X-ray powder diffraction), SEM-EDS (scanning electron microscopy–energy-dispersive spectrometry), FT-IR (Fourier transform infrared) spectroscopy and ICP-OES (inductively coupled plasma–optical emission spectrometry) techniques were used. A further study of luminescent properties and cytocompatibility showed that the obtained HVps co-doped with Sr2+ and Tb3+ ions are highly biocompatible and able to enhance the proliferation process and can therefore be potentially used as fluorescent probes or in regenerative medicine.

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39

Hafeez, Abdul, Zareen Akhter, John F. Gallagher, Nawazish Ali Khan, Asghari Gul, and Faiz Ullah Shah. "Synthesis, Crystal Structures, and Spectroscopic Characterization of Bis-aldehyde Monomers and Their Electrically Conductive Pristine Polyazomethines." Polymers 11, no. 9 (September 13, 2019): 1498. http://dx.doi.org/10.3390/polym11091498.

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Bis-aldehyde monomers 4-(4′-formyl-phenoxy)benzaldehyde (3a), 3-methoxy-4-(4′-formyl-phenoxy)benzaldehyde (3b), and 3-ethoxy-4-(4′-formyl-phenoxy)benzaldehyde (3c) were synthesized by etherification of 4-fluorobenzaldehyde (1) with 4-hydroxybenzaldehyde (2a), 3-methoxy-4-hydroxybenzaldehyde (2b), and 3-ethoxy-4-hydroxybenzaldehyde (2c), respectively. Each monomer was polymerized with p-phenylenediamine and 4,4′-diaminodiphenyl ether to yield six poly(azomethine)s. Single crystal X-ray diffraction structures of 3b and 3c were determined. The structural characterization of the monomers and poly(azomethine)s was performed by FT-IR and NMR spectroscopic techniques and elemental analysis. Physicochemical properties of polymers were investigated by powder X-ray diffraction, thermogravimetric analysis (TGA), viscometry, UV–vis, spectroscopy and photoluminescence. These polymers were subjected to electrical conductivity measurements by the four-probe method, and their conductivities were found to be in the range 4.0 × 10−5 to 6.4 × 10−5 Scm−1, which was significantly higher than the values reported so far.

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Śmigiel-Kamińska, Daria, Jan Pośpiech, Joanna Makowska, Piotr Stepnowski, Jolanta Wąs-Gubała, and Jolanta Kumirska. "The Identification of Polyester Fibers Dyed with Disperse Dyes for Forensic Purposes." Molecules 24, no. 3 (February 10, 2019): 613. http://dx.doi.org/10.3390/molecules24030613.

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In forensic laboratories, the most commonly analyzed microtraces are microscopic fragments of single fibers. One of the main goals of the examination of fragments of fibers a few millimeters long is to determine their characteristic physicochemical properties and compare them with fibers originating from a known source (e.g., a suspect’s clothes). The color and dyes of fiber microtraces play an important role in their research and evaluation, being analyzed by means of microscopic, spectroscopic, and chromatographic methods. The results of examinations conducted with the use of spectroscopic techniques might be ambiguous due to overlapping bands of absorption and the transmission and dispersion of electromagnetic radiation corresponding to the specific chemical structure of the fibers and their dyes. For this reason, it is very important to improve currently available spectroscopic methods and/or to propose new ones that allow evidential materials to be analyzed in a much more reliable way. In this review, the possibility of the use of chromatographic techniques with different detection systems for such analyses is underlined. This review covers the different analytical methods used in the forensic analysis of polyester fibers dyed with disperse dyes. Polyester fibers occupy the first position among synthetic fibers in their use for a variety of purposes, and disperse dyes are commonly applied for dyeing them.

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Hasan, Hamad M. I., Aaza I. Yahiya, Safaa S. Hassan, and Mabrouk M. Salama. "Biological Study of Transition Metal Complexes with Adenine Ligand." Proceedings 41, no. 1 (November 14, 2019): 77. http://dx.doi.org/10.3390/ecsoc-23-06601.

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Adenine complexes were prepared with some of the first series transition metals in a stoichiometric ratio of 1: 2 (Mn+: L), where Mn+ = Mn2+, Fe3+, Co2+, Ni2+, Cu2+, Zn2+, and Cd2+ ions. The Complexes were characterized by the physicochemical and spectroscopic techniques as electric conductivity, metal contents, IR, UV–Visible, and molar conductance techniques. The stoichiometric ratios of the synthesized complexes were confirmed by using molar ratio method. The dissociation constant of adenine ligand was determined spectrophotometrically. Solvent effect on the electronic spectra of the adenine ligand was examined using solvents with different polarities. The biological activity of adenine ligand and its metal complexes were tested in vitro against some selected species of fungi and bacteria. The results showed a satisfactory spectrum against the tested organisms.

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Patel, R. N., S. P. Rawat, and Mukesh Choudhary. "Synthesis, Electrochemical, Spectroscopic, Antimicrobial, and Superoxide Dismutase Activity of Nickel (II) Complexes with Bidentate Schiff Bases." International Journal of Inorganic Chemistry 2013 (December 19, 2013): 1–8. http://dx.doi.org/10.1155/2013/617837.

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Five new nickel (II) complexes, namely, [Ni(L1)2](ClO4)2(1); [Ni(L2)2](ClO4)2(2); [Ni(L3)2](ClO4)2(3); [Ni(L4)2](ClO4)2(4); [Ni(L5)2](ClO4)2(5), where L1 = benzoylhydrazide; L2 = N-[(1)-1-(2-methylphenyl)ethylidene]benzohydrazide; L3=N-[(1)-1-(4-methylphenyl)ethylidene]benzohydrazide; L4=N-[(1)-1-(2-methoxyphenyl)ethylidene]benzohydrazide; L5 = N-[(1)-1-(4-methoxy-phenyl)ethylidene]benzohydrazide, have been synthesized and characterized by various physicochemical and spectroscopic techniques. The synthesized complexes are stable powders, insoluble in common organic solvents such as ethanol, benzene, carbon tetrachloride, chloroform, and diethyl ether, and are nonelectrolytes. The magnetic and spectroscopic data indicate a distorted square planar geometry for all complexes. The superoxide dismutase activity of these complexes has been measured and discussed. Antibacterial and antifungal properties of these complexes were also tested.

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Botto, Irma Lia, María Elena Canafoglia, Delia Gazzoli, and María José González. "Spectroscopic and Microscopic Characterization of Volcanic Ash from Puyehue-(Chile) Eruption: Preliminary Approach for the Application in the Arsenic Removal." Journal of Spectroscopy 2013 (2013): 1–8. http://dx.doi.org/10.1155/2013/254517.

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Volcanic ash from Puyehue Cordon Caulle Volcanic Complex (Chile), emitted on June 4, 2011, and deposited in Villa La Angostura at ~40 km of the source, was collected and analyzed by Raman spectroscopy, optical and scanning electron microscopy (SEM-EDS), X-ray diffraction (XRD), surface area (BET), and chemical analysis (ICP-AES-MS technique). The mineralogical and physicochemical study revealed that the pyroclastic mixture contains iron oxides in the form of magnetite and hematite as well as pyroxene and plagioclase mineral species and amorphous pumiceous shards. Carbonaceous material was also identified. Physicochemical techniques allow us to select two representative samples (average composition and Fe-rich materials) which were used to analyze their performances in the adsorption process to remove arsenic from water. Additional iron activation by means of ferric salts was performed under original sample. Results showed that the low-cost feedstock exhibited a good adsorption capacity to remove the contaminant, depending on the iron content and the water pH.

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Arul, Velusamy, Kothalam Radhakrishnan, Natarajan Sampathkumar, Jothi Vinoth Kumar, Natarajan Abirami, and Baskaran Stephen Inbaraj. "Detoxification of Toxic Organic Dye by Heteroatom-Doped Fluorescent Carbon Dots Prepared by Green Hydrothermal Method Using Garcinia mangostana Extract." Agronomy 13, no. 1 (January 9, 2023): 205. http://dx.doi.org/10.3390/agronomy13010205.

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In this work, nitrogen- and oxygen-doped fluorescent carbon dots (NOFCDs) were prepared using a simple green hydrothermal carbonization technique. Aqueous ammonia and the plant extract of Garcinia mangostana were used as a source of nitrogen and carbon, respectively. The prepared NOFCDs were examined using a variety of microscopic and spectroscopic techniques for physicochemical characterization. Fluorescence and UV–visible spectroscopy measurements were used to analyze the NOFCDs’ excitation-dependent fluorescent emission and absorption nature. It is observed that fluorescence intensity was excited at 320 nm and the strongest emission peak absorbed at 405 nm. The HRTEM imaging revealed NOFCDs to be spherical in shape with particle size at 3.58 nm. Moreover, the amorphous nature of NOFCDs was verified by X-ray diffraction, Raman spectroscopy, and SAED pattern techniques. Through FTIR, XPS, and EDS investigations, the doping of nitrogen and oxygen over the surface of the NOFCDs was evaluated and validated. The presence of carboxylic, amine, hydroxyl, and carbonyl functional groups on NOFCDs’ surface was shown by XPS and FTIR investigations. By using NaBH4, the obtained NOFCDs were demonstrated to possess excellent catalytic activity in the detoxification of methylene blue. Overall, this study revealed that the NOFCDs synthesized from green sources could be a promising material for catalytic and environmental remediation applications.

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Salman, Abbas Washeel, Zainab Nashaat Al-Saadi, Hayder Dawood Arkawazi, and Michaele J. Hardie. "Synthesis, Characterization and Antibacterial Activity of Some Transition Metal Complexes Derived from the Ligand N-Benzylimidazole Against Methicillin-Resistantt Staphylococcus Aureus (Mrsa)." International Journal of Drug Delivery Technology 9, no. 04 (December 25, 2019): 666–70. http://dx.doi.org/10.25258/ijddt.9.4.25.

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Metal complexes of the ligand N-benzylimidazole (BnIm) and their in vitro antibacterial study are reported. The complexes of Co(II), Ni(II), Cu(II), Zn(II), and Ag(I) were synthesized by the reaction of the ligand with appropriate metal salt in 1:4 metal to ligand mole ratio. All the synthesized ligand and their complexes were characterized by physicochemical and spectroscopic techniques. Further, the compounds were screened for their antibacterial activity against a multi-resistance strain of Staphylococcus aureus (MRSA) using ciprofloxacin as a standard antibiotic. In general, all the tested compounds showed antibacterial activities at minimum inhibition concentration (MIC) level.

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Cheng, Hang, Jiangliang Hu, Dongxia Wu, Weiren Bao, Changming Hou, Xianyan Lv, Liping Chang, and Jiancheng Wang. "Effect of Interaction between Pt and Different Crystalline Phases of TiO2 on Benzene Oxidation." Catalysts 14, no. 4 (March 31, 2024): 234. http://dx.doi.org/10.3390/catal14040234.

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To evaluate the effects of different TiO2 crystalline phases on the catalytic oxidation performance of benzene on Pt-loaded TiO2 catalysts, physicochemical examinations were conducted using several spectroscopic and analytical techniques. Obvious effects on the valence state and morphology of Pt were exhibited by different crystalline phases. The rutile phase favored the formation of specific Pt(111) crystal faces, which enhanced the amount of surface-active oxygen species. Moreover, the àPt-O-Ti species was formed between Pt4+ and Ti at the edge of the Pt nanoparticles, promoting both electron flow and the transfer of reactive oxygen species, thus accounting for catalytic activity.

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Moreira, Leonardo Marmo, Alessandra Lima Poli, Juliana Pereira Lyon, Flávio Aimbire, José Carlos Toledo, Antonio José Costa-Filho, and Hidetake Imasato. "Ligand changes in ferric species of the giant extracellular hemoglobin of Glossoscolex paulistus as function of pH: correlations between redox, spectroscopic and oligomeric properties and general implications with different hemoproteins." Journal of Porphyrins and Phthalocyanines 14, no. 03 (March 2010): 199–218. http://dx.doi.org/10.1142/s108842461000201x.

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The present review is focused on the relationship between oligomeric and heme properties of HbGp, emphasizing the characteristics that can be generalized to other hemoproteins. This study represents the state-of-the-art with respect to the approaches for investigating giant extracellular hemoglobins as well as the correlation between oligomeric assembly alterations and their consequent changes in the first coordination sphere. A wide introduction focused on the properties of this hemoglobin is developed. Indeed, this hemoprotein is considered an interesting prototype of blood substitute and biosensor due to its peculiar properties, such as resistance to autoxidation and oligomeric stability. Previous studies by our group employing UV-vis, EPR and CD spectroscopies have been revised in a complete approach, in agreement with recent and relevant data from the literature. In fact, a consistent and inter-related spectroscopic study is described propitiating a wide assignment of "fingerprint" peaks found in the techniques evaluated in this paper. This review furnishes physicochemical information regarding the identification of ferric heme species of hemoproteins and metallic complexes through their spectroscopic bands. This effort at the attribution of UV-vis, EPR and CD peaks is not restricted to HbGp, and includes a comparative analysis of several hemoproteins involving relevant implications regarding several types of iron-porphyrin systems.

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48

Papadopoulos, Zisis, Efstratia Doulopoulou, Ariadni Zianna, Antonios G. Hatzidimitriou, and George Psomas. "Copper(II) Complexes of 5–Fluoro–Salicylaldehyde: Synthesis, Characterization, Antioxidant Properties, Interaction with DNA and Serum Albumins." Molecules 27, no. 24 (December 15, 2022): 8929. http://dx.doi.org/10.3390/molecules27248929.

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The synthesis, characterization and biological profile (antioxidant capacity, interaction with calf-thymus DNA and serum albumins) of five neutral copper(II) complexes of 5–fluoro–salicylaldehyde in the absence or presence of the N,N’–donor co–ligands 2,2′–bipyridylamine, 2,9–dimethyl–1,10–phenanthroline, 1,10–phenanthroline and 2,2′–bipyridine are presented herein. The compounds were characterized by physicochemical and spectroscopic techniques. The crystal structures of four complexes were determined by single-crystal X-ray crystallography. The ability of the complexes to scavenge 1,1–diphenyl–picrylhydrazyl and 2,2′–azinobis(3–ethylbenzothiazoline–6–sulfonic acid) radicals and to reduce H2O2 was investigated in order to evaluate their antioxidant activity. The interaction of the compounds with calf-thymus DNA possibly takes place via intercalation as suggested by UV–vis spectroscopy and DNA–viscosity titration studies and via competitive studies with ethidium bromide. The affinity of the complexes with bovine and human serum albumins was examined by fluorescence emission spectroscopy revealing the tight and reversible binding of the complexes with the albumins.

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49

Borole, Vipin Y., and Sonali B. Kulkarni. "Correlation of pH on Soil Physicochemical Properties using Linear Regression Model for Spectral Data Analysis." International Journal of Advanced Remote Sensing and GIS 10, no. 1 (July 17, 2021): 3492–500. http://dx.doi.org/10.23953/cloud.ijarsg.504.

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Soil properties may be varied by spatially and temporally with different agricultural practices. An accurate and reliable soil properties assessment is challenging issue in soil analysis. The soil properties assessment is very important for understanding the soil properties, nutrient management, influence of fertilizers and relation between soil properties which are affecting the plant growth. Conventional laboratory methods used to analyses soil properties are generally impractical because they are time-consuming, expensive and sometimes imprecise. On other hand, Visible and infrared spectroscopy can effectively characterize soil. Spectroscopic measurements are rapid, precise and inexpensive. Soil spectroscopy has shown to be a fast, cost-effective, environmentally friendly, non-destructive, reproducible and repeatable analytical technique. In the present research, we use spectroscopy techniques for soil properties analysis. The spectra of agglomerated farming soils were acquired by the ASD Field spec 4 spectroradiometer. Different fertilizers treatment applied soil samples are collected in pre monsoon and post monsoon season for 2 year (4 season) for banana and cotton crops in the form of DS-I and DS-II respectively. The soil spectra of VNIR region were preprocessed to get pure spectra. Then process the acquired spectral data by statistical methods for quantitative analysis of soil properties. The detected soil properties were carbon, Nitrogen, soil organic matter, pH, phosphorus, potassium, moisture sand, silt and clay. Soil pH is most important chemical properties that describe the relative acidity or alkalinity of the soil. It directly effect on plant growth and other soil properties. The relationship between pH properties on soil physical and chemical parameters and their influence were analyses by using linear regression model and show the performance of regression model with R2 and RMSE. Keywords soil; physicochemical properties; spectroscopy; pH

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Princey, J. Morris, A. Nandhini A. Nandhini, G. Poojadevi G. Poojadevi, and S. Nobil Divya. "Antimicrobial Activity and Physicochemical Analysis of Bio-degradable Films from Cucurbita pepo and Musa paradisiaca." Oriental Journal Of Chemistry 37, no. 6 (December 30, 2021): 1434–39. http://dx.doi.org/10.13005/ojc/370623.

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Cucurbita pepo and Musa paradisiaca can be considered as a large source of starch which makes it appropriate to be used for the preparation of bio-plastic material. In this study, biodegradable films from Cucurbita pepo and Musa paradisiaca were developed and investigated for their properties like pH, ash, moisture content, amylose content, biodegradability, and antimicrobial activity. 1,2,3-Propanetriol, gingelly oil, and agarose gel was used to reduce the brittleness of the developed starch- based bioplastic films. The investigation of films was done by Spectroscopic and Surface Analysis techniques. The developed bio- films showed substantial properties like less engorgement and insolubility in water which makes it worth a commercial viable product for food packaging.

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Journal articles on the topic 'Spectroscopic and physicochemical techniques'

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