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Articles de revues sur le sujet "LC-DS/MS"
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Nemutlu, Emirhan, Gokcen Orgul, Tuba Recber, Emine Aydin, Ece Ozkan, Mert Turgal, Mehmet Alikasifoglu, Sedef Kir et Mehmet Sinan Beksac. « Metabolic Infrastructure of Pregnant Women With Trisomy 21 Fetuses ; Metabolomic Analysis ». Zeitschrift für Geburtshilfe und Neonatologie 223, no 05 (27 mai 2019) : 297–303. http://dx.doi.org/10.1055/a-0877-7869.
Texte intégralRésumé :
AbstractWe aimed to configure impaired/altered metabolomic profiles of pregnant women carrying Down syndrome (DS) fetuses. The study involved 21 and 32 pregnant women with DS and euploid fetuses, respectively, as determined by prenatal screening and diagnosis as part of an antenatal care program. Metabolomic analyses were carried out using gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-quadrupole time-of-flight mass spectrometry (LC-qTOF-MS) methods. A total of 95 metabolites were identified. GC-MS analysis indicated that levels of 2-hydroxybutyric acid, benzoic acid, nonanoic acid, 3-hydroxybutyric acid, and 2-ketoisocaproic acid were increased in the DS group, where beta-alanine, threonic acid, oxalic acid, alpha-tocopherol, uracil, 2-piperidone, and creatinine were decreased. However, LC-qTOF-MS analysis showed that lipid-related metabolites were decreased in women carrying DS fetuses, whereas creatine, N4-phosphoagmatine, citrate, 2,5-dioxopentanoate, 2-furoate, pyruvate, and fructose levels were increased. Pathway analysis was also performed using metabolites whose levels were significantly altered (p<0.05) between the groups, and the findings indicated that the biosynthesis pathways of aminoacyl-tRNA and “valine-leucine-isoleucine”, and metabolism pathways of “glycine-serine-threonine”, nitrogen, “alanine-aspartate-glutamate”, propanoate, glycerophospholipid, cysteine, methionine, and phenylalanine were significantly altered. Our findings indicate a special type of metabolic status/syndrome in pregnant women with Down syndrome fetuses. It could be speculated that altered metabolic status might influence both gametogenesis and embryogenesis. Down syndrome is a complex genetic disorder that is important to detect prenatally, but may also be prevented by taking necessary precautions prior to pregnancy.
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Hu, Wei, Ning Liu, Yuhua Tian et Lianxue Zhang. « Molecular Cloning, Expression, Purification, and Functional Characterization of Dammarenediol Synthase fromPanax ginseng ». BioMed Research International 2013 (2013) : 1–7. http://dx.doi.org/10.1155/2013/285740.
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The objective of this study is to clone and charecterize the expression of dammarenediol synthase gene and then to determine the relationship between the expression of dammarenediol synthase gene that is involved in the ginsenoside biosynthetic pathway and the ginsenoside content. A cDNA phage library was constructed from a five-year-old ginseng root. The cDNA library was screened for the dammarenediol synthase gene by using its specific primers. It was further cloned and expressed in pET-30a vector. The recombinant plasmid pET-30a-DS was expressed in RosettaE. coli. The recombinant DS protein was purified by affinity chromatography. The production of dammarenediol was detected by liquid chromatography-mass spectrometry (LC-MS). Results showed that dammarenediol synthase gene was cloned from the cDNA library and was expressed in RosettaE. coliand the SDS-PAGE analysis showed the presence of purified DS protein. LS-MS showed the activity of DS protein, as the protein content increases the dammarenediol increases. Our results indicate that the recombinant dammarenediol synthase protein could increase the production of dammarenediol and the expression of DS played a vital role in the biosynthesis of ginsenosides inP. ginseng.
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Polo, Giulia, Daniela Gueraldi, Antonella Giuliani, Laura Rubert, Chiara Cazzorla, Leonardo Salviati, Antonio Marzollo, Alessandra Biffi, Alessandro P. Burlina et Alberto B. Burlina. « The combined use of enzyme activity and metabolite assays as a strategy for newborn screening of mucopolysaccharidosis type I ». Clinical Chemistry and Laboratory Medicine (CCLM) 58, no 12 (26 novembre 2020) : 2063–72. http://dx.doi.org/10.1515/cclm-2020-0064.
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AbstractObjectivesMucopolysaccharidosis type I (MPS I) was added to our expanded screening panel in 2015. Since then, 127,869 newborns were screened by measuring α-L-iduronidase (IDUA) enzyme activity with liquid chromatography tandem mass spectrometry (LC-MS/MS). High false positives due to frequent pseudodeficiency alleles prompted us to develop a second-tier test to quantify glycosaminoglycan (GAG) levels in dried blood spot (DBS).MethodsHeparan-sulfate (HS) and dermatan-sulfate (DS) were measured with LC-MS/MS after methanolysis. DBSs were incubated with methanolic-HCl 3 N at 65 °C for 45 min. Chromatographic separation used an amide column with a gradient of acetonitrile and water with 10 mM ammonium acetate in a 9-min run. The method was validated for specificity, linearity, lower limit of quantification (LOQ), accuracy and precision.ResultsIntra- and inter-day coefficients of variation were <15% for both metabolites. Reference values in 40 healthy newborns were: HS mean 1.0 mg/L, 0–3.2; DS mean 1.5 mg/L, 0.5–2.7). The two confirmed newborn MPS I patients had elevated HS (4.9–10.4 mg/L, n.v. <3.2) and DS (7.4–8.8 mg/L, n.v. <2.7). Since its introduction in February 2019, the second-tier test reduced the recall rate from 0.046% to 0.006%. Among 127,869 specimens screened, the incidence was 1:63,935 live births. Both patients started enzyme replacement therapy (ERT) within 15 days of birth and one of them received allogenic hematopoietic stem cell transplantation (HSCT) at ht age of 6 months.ConclusionsGAGs in DBS increased the specificity of newborn screening for MPS I by reducing false-positives due to heterozygosity or pseudodeficiency. Early diagnosis and therapeutical approach has improved the outcome of our patients with MPS I.
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Mancini, Ilaria, Guido Domingo, Marcella Bracale, Francesco Loreto et Susanna Pollastri. « Isoprene Emission Influences the Proteomic Profile of Arabidopsis Plants under Well-Watered and Drought-Stress Conditions ». International Journal of Molecular Sciences 23, no 7 (30 mars 2022) : 3836. http://dx.doi.org/10.3390/ijms23073836.
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Isoprene is a small lipophilic molecule synthesized in plastids and abundantly released into the atmosphere. Isoprene-emitting plants are better protected against abiotic stresses, but the mechanism of action of isoprene is still under debate. In this study, we compared the physiological responses and proteomic profiles of Arabidopsis which express the isoprene synthase (ISPS) gene and emit isoprene with those of non-emitting plants under both drought-stress (DS) and well-watered (WW) conditions. We aimed to investigate whether isoprene-emitting plants displayed a different proteomic profile that is consistent with the metabolic changes already reported. Only ISPS DS plants were able to maintain the same photosynthesis and fresh weight of WW plants. LC–MS/MS-based proteomic analysis revealed changes in protein abundance that were dependent on the capacity for emitting isoprene in addition to those caused by the DS. The majority of the proteins changed in response to the interaction between DS and isoprene emission. These include proteins that are associated with the activation of secondary metabolisms leading to ABA, trehalose, and proline accumulations. Overall, our proteomic data suggest that isoprene exerts its protective mechanism at different levels: under drought stress, isoprene affects the abundance of chloroplast proteins, confirming a strong direct or indirect antioxidant action and also modulates signaling and hormone pathways, especially those controlling ABA synthesis. Unexpectedly, isoprene also alters membrane trafficking.
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Lin, Lee, Lo, Tu, Chang, Chang, Chiu et al. « An At-Risk Population Screening Program for Mucopolysaccharidoses by Measuring Urinary Glycosaminoglycans in Taiwan ». Diagnostics 9, no 4 (5 octobre 2019) : 140. http://dx.doi.org/10.3390/diagnostics9040140.
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Background: The mucopolysaccharidoses (MPSs) are a group of rare lysosomal storage disorders characterized by the accumulation of glycosaminoglycans (GAGs) and which eventually cause progressive damage to various tissues and organs. We developed a feasible MPS screening algorithm and established a cross-specialty collaboration platform between medical geneticists and other medical specialists based on at-risk criteria to allow for an earlier confirmative diagnosis of MPS. Methods: Children (<19 years of age) with clinical signs and symptoms compatible with MPS were prospectively enrolled from pediatric clinics between July 2013 and June 2018. Urine samples were collected for a non-specific total GAG analysis using the dimethylmethylene blue (DMB) spectrophotometric method, and the quantitation of three urinary GAGs (dermatan sulfate (DS), heparan sulfate (HS), and keratan sulfate (KS)) was performed by liquid chromatography/tandem mass spectrometry (LC-MS/MS). The subjects with elevated urinary GAG levels were recalled for leukocyte enzyme activity assay and genetic testing for confirmation. Results: Among 153 subjects enrolled in this study, 13 had a confirmative diagnosis of MPS (age range, 0.6 to 10.9 years—three with MPS I, four with MPS II, five with MPS IIIB, and one with MPS IVA). The major signs and symptoms with regards to different systems recorded by pediatricians at the time of the decision to test for MPS were the musculoskeletal system (55%), followed by the neurological system (45%) and coarse facial features (39%). For these 13 patients, the median age at the diagnosis of MPS was 2.9 years. The false negative rate of urinary DMB ratio using the dye-based method for these 13 patients was 31%, including one MPS I, two MPS IIIB, and one MPS IVA. However, there were no false negative results with urinary DS, HS and KS using the MS/MS-based method. Conclusions: We established an at-risk population screening program for MPS by measuring urinary GAG fractionation biomarkers using the LC-MS/MS method. The program included medical geneticists and other medical specialists to increase awareness and enable an early diagnosis by detecting MPS at the initial onset of clinical symptoms.
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Tyrtyshnaia, Anna, Sophia Konovalova, Arina Ponomarenko, Anastasia Egoraeva et Igor Manzhulo. « Fatty Acid-Derived N-acylethanolamines Dietary Supplementation Attenuates Neuroinflammation and Cognitive Impairment in LPS Murine Model ». Nutrients 14, no 18 (19 septembre 2022) : 3879. http://dx.doi.org/10.3390/nu14183879.
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Neuroinflammation plays a critical role in the pathogenesis of most neurological and neurodegenerative diseases and therefore represents a potential therapeutic target. In this regard, accelerating the resolution process in chronic neuroinflammation may be an effective strategy to deal with the cognitive consequences of neuropathology and generalized inflammatory processes. N-acylethanolamine (NAE) derivatives of fatty acids, being highly active lipid mediators, possess pro-resolving activity in inflammatory processes and are promising agents for the suppression of neuroinflammation and its consequences. This paper is devoted to a study of the effects played by dietary supplement (DS), containing a composition of fatty acid-derived NAEs, obtained from squid Berryteuthis magister, on the hippocampal neuroinflammatory and memory processes. By detecting the production of pro-inflammatory cytokines and glial markers, a pronounced anti-inflammatory activity of DS was demonstrated both in vitro and in vivo. DS administration reversed the LPS-induced reduction in hippocampal neurogenesis and memory deterioration. LC-MS analysis revealed an increase in the production of a range of NAEs with well-documented anti-inflammatory activity in response to the administered lipid composition. To conclude, we found that tested DS suppresses the neuroinflammatory response by reducing glial activation, positively regulates neural progenitor proliferation, and attenuates hippocampal-dependent memory impairment.
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Yang, Yan, et Jianqing Wu. « Significance of the Differential Peptidome in Multidrug-Resistant Tuberculosis ». BioMed Research International 2019 (17 janvier 2019) : 1–12. http://dx.doi.org/10.1155/2019/5653424.
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Most multidrug-resistant tuberculosis (MDR-TB) patients fail to receive a timely diagnosis and treatment. Therefore, we explored the differentially expressed peptides in MDR-TB compared with drug-susceptible tuberculosis (DS-TB) patients using LC-MS/MS and Ingenuity Pathway Analysis (IPA) to analyse the potential significance of these differentially expressed peptides. A total of 301 peptides were differentially expressed between MDR-TB and DS-TB groups. Of these, 24 and 16 peptides exhibited presented high (fold change ≥ 2.0, P < 0.05) and low (fold change ≤ −2.0, P < 0.05) levels in MDR-TB. Significant canonical pathways included the prothrombin activation system, coagulation system, and complement system. In the network of differentially expressed precursor proteins, lipopolysaccharide (LPS) regulates many precursor proteins, including four proteins correlated with organism survival. These four important differentially expressed proteins are prothrombin (F2), complement receptor type 2 (CR2), collagen alpha-2(V) chain (COL5A2), and inter-alpha-trypsin inhibitor heavy chain H4 (ITIH4). After addition of CR2 peptide, IL-6 mRNA expression in THP-1 cells decreased significantly in dose- and time-dependent manners. Cumulatively, our study proposes potential biomarkers for MDR-TB diagnosis and enables a better understanding of the pathogenesis of MDR-TB. The functions of differentially expressed peptides, especially CR2, in MDR-TB require further investigation.
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Wagener, Felicitas, Sven Guddat, Christian Görgens, Yiannis S. Angelis, Michael Petrou, Andreas Lagojda, Dirk Kühne et Mario Thevis. « Investigations into the elimination profiles and metabolite ratios of micro-dosed selective androgen receptor modulator LGD-4033 for doping control purposes ». Analytical and Bioanalytical Chemistry 414, no 2 (4 novembre 2021) : 1151–62. http://dx.doi.org/10.1007/s00216-021-03740-7.
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AbstractLGD-4033 (ligandrol) is a selective androgen receptor modulator (SARM), which is prohibited in sports by the World Anti-Doping Agency (WADA) and led to 62 adverse analytical findings (AAFs) in 2019. But not only deliberate doping with LGD-4033 constitutes a problem. In the past years, some AAFs that concerned SARMs can be attributed to contaminated dietary supplements (DS). Thus, the urgency to develop methods to differentiate between inadvertent doping and abuse of SARMs to benefit from the performance-enhancing effect of the compound in sports is growing. To gain a better understanding of the metabolism and excretion patterns of LGD-4033, human micro-dose excretion studies at 1, 10, and 50 µg LGD-4033 were conducted. Collected urine samples were prepared for analysis using enzymatic hydrolysis followed by solid-phase extraction and analyzed via LC-HRMS/MS. Including isomers, a total of 15 phase I metabolites were detected in the urine samples. The LC-HRMS/MS method was validated for qualitative detection of LGD-4033, allowing for a limit of detection (LOD) of 8 pg/mL. The metabolite M1, representing the epimer of LGD-4033, was synthesized and the structure elucidated by NMR spectroscopy. As the M1/LGD-4033 ratio changes over time, the ratio and the approximate LGD-4033 concentration can contribute to estimating the time point of drug intake and dose of LGD-4033 in doping control urine samples, which is particularly relevant in anti-doping result management. Graphical abstract
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Xu, Lili, Yang Jiao, Weiliang Cui, Bing Wang, Dongxiao Guo, Fei Xue, Xiangrong Mu, Huifen Li, Yongqiang Lin et Huibin Lin. « Quality Evaluation of Traditional Chinese Medicine Prescription in Naolingsu Capsule Based on Combinative Method of Fingerprint, Quantitative Determination, and Chemometrics ». Journal of Analytical Methods in Chemistry 2022 (22 août 2022) : 1–11. http://dx.doi.org/10.1155/2022/1429074.
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Background. Naolingsu capsule (NLSC) is a well-known traditional Chinese medicine (TCM) prescription in China. It is widely used to treat neurasthenia, insomnia, cardiovascular and cerebrovascular disease, and other diseases. However, its inalienable chemical groups have not been carried out. Methods. We first established the nontargeted investigation based on fingerprinting coupled with UHPLC-Q/TOF-MS/MS. Second, the quantitative methods based on HPLC-DAD and LC-MS/MS were connected to the synchronous quantitative assurance of eleven and fourteen marker compounds. Finally, the quantitative information was processed with SIMCA-P for differentiating the distinctive bunches of samples to screen the foremost appropriate chemical markers. Results. The similarity of HPLC fingerprints of 24 batches of NLSC samples was 0.645–0.992. In total, 37 flavonoids, 21 organic acids, 22 lignans, 13 saponins, and 20 other compounds were recognized in NLSC by the UHPLC-Q/TOF-MS/MS method. The quantitative determination was approved for linearity, discovery limits, accuracy, repeatability, soundness, and precision. Principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) models accomplished the great classification of the samples from the five enterprises, respectively. Rehmannioside D (RD), methylophiopogonanone A (MPA), 3,6′-disinapoyl sucrose (DS), schisandrin B (SSB), epimedin C (EC), icariin (ICA), and jujuboside B (JB) were considered as the potential chemical markers for NLSC quality control. Conclusion. The experimental results illustrated that the combinative strategy was valuable for quick pharmaceutical quality assessment, which can potentially differentiate the origin, decide the realness, and assess the overall quality of the formulation.
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Arunkumar, Nivethitha, Dung Chi Vu, Shaukat Khan, Hironori Kobayashi, Thi Bich Ngoc Can, Tsubasa Oguni, Jun Watanabe et al. « Diagnosis of Mucopolysaccharidoses and Mucolipidosis by Assaying Multiplex Enzymes and Glycosaminoglycans ». Diagnostics 11, no 8 (27 juillet 2021) : 1347. http://dx.doi.org/10.3390/diagnostics11081347.
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Mucopolysaccharidoses (MPS) and mucolipidosis (ML II/III) are a group of lysosomal storage disorders (LSDs) that occur due to a dysfunction of the lysosomal hydrolases responsible for the catabolism of glycosaminoglycans (GAGs). However, ML is caused by a deficiency of the enzyme uridine-diphosphate N-acetylglucosamine:lysosomal-enzyme-N-acetylglucosamine-1-phosphotransferase (GlcNAc-1-phosphotransferase, EC2.7.8.17), which tags lysosomal enzymes with a mannose 6-phosphate (M6P) marker for transport to the lysosome. A timely diagnosis of MPS and ML can lead to appropriate therapeutic options for patients. To improve the accuracy of diagnosis for MPS and ML in a high-risk population, we propose a combination method based on known biomarkers, enzyme activities, and specific GAGs. We measured five lysosomal enzymes (α-L-iduronidase (MPS I), iduronate-2-sulfatase (MPS II), α-N-acetylglucosaminidase (MPS IIIB), N-acetylglucosamine-6-sulfatase (MPS IVA), and N-acetylglucosamine-4-sulfatase (MPS VI)) and five GAGs (two kinds of heparan sulfate (HS), dermatan sulfate (DS), and two kinds of keratan sulfate (KS)) in dried blood samples (DBS) to diagnose suspected MPS patients by five-plex enzyme and simultaneous five GAGs assays. We used liquid chromatography-tandem mass spectrometry (LC-MS/MS) for both assays. These combined assays were tested for 43 patients with suspected MPS and 103 normal control subjects. We diagnosed two MPS I, thirteen MPS II, one MPS IIIB, three MPS IVA, two MPS VI, and six ML patients with this combined method, where enzymes, GAGs, and clinical manifestations were compatible. The remaining 16 patients were not diagnosed with MPS or ML. The five-plex enzyme assay successfully identified MPS patients from controls. Patients with MPS I, MPS II, and MPS IIIB had significantly elevated HS and DS levels in DBS. Compared to age-matched controls, patients with ML and MPS had significantly elevated mono-sulfated KS and di-sulfated KS levels. The results indicated that the combination method could distinguish these affected patients with MPS or ML from healthy controls. Overall, this study has shown that this combined method is effective and can be implemented in larger populations, including newborn screening.
Thèses sur le sujet "LC-DS/MS"
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Pingeon, Marine. « Development and validation of analytical methods for therapeutic drug monitoring ». Doctoral thesis, Universita degli studi di Salerno, 2019. http://elea.unisa.it:8080/xmlui/handle/10556/4509.
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2017 - 2018The U.S. Food and Drug Administration defines as Precision or Personalized Medicine (PM) an innovative therapeutic approach that tailors therapy and prevention on patients based on inter-individual variabilities in molecular or environmental features and in lifestyles. The major goals of PM are to maximize treatment efficacy and to reduce cost, toxicities and therapy failure rates by early identification of patients who might benefit or not of a specific treatment. In this scenario, therapeutic drug monitoring (TDM) is an important laboratory tool for PM because of the possibility to measure several drugs and bioactive molecules in human biological matrices. TDM is based on the hypothesis that in the majority of drugs, there is a relationship between administered dose and circulating concentration of unbound fraction - and between this concentration and observed pharmacological effects. TDM is recommended for drugs with significant inter-individual pharmacokinetic variability and an established relationship between blood concentrations and clinical efficacy and/or toxicity. Moreover, TDM is also advisable in special populations such as pregnant women and children. To date, liquid chromatography and immunometric assay are still considered the standard for molecule measurement in biological fluids; however, in recent years, LC tandem mass spectrometry (LC-MS) is gaining popularity because of the possibility of in-depth and multiplexed analysis with high selectivity and specificity. During this Ph.D. program, we developed several high performance LC (HPLC)- and LC-MS/MS-based approaches for TDM of different drugs measured in various types of body fluids and validated according to EMA and FDA guidelines. In particular, we focused on: 1) TDM of hydroxychloroquine (HCQ) blood concentration, a drug with a wide therapeutic window. Our method was validated on a cohort of patients with Systemic Lupus Erythematosus treated with HCQ and blood concentrations were correlated to several clinical parameters, such quality of life. Moreover, TDM of HCQ was also used to monitor treatment adherence in those subjects. 2) TDM of a commonly used chemotherapeutic agent, the 5-fluorouracil (5-FU), which is known to have a narrow therapeutic window and a high toxicity 3) TDM of a new kinase inhibitor, Ruxolitinib, approved for the treatment of myeloproliferative hematologic disorders. 4) TDM of several drugs, such as caffeine and phenobarbital, in newborns who are at particular risk of uncorrected drug dosage. Due to the need to carry out analyses on very-small volume samples, we validated an analytical method using micro-sampling techniques such as the dried blood spot (DBS) sampling combined with LC-MS/MS analysis. [edited by author]
XVII n.s. (XXXI ciclo)
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Conrado, Marli 1972, Marcos Rivail da 1956 Silva et Universidade Regional de Blumenau Programa de Pós-Graduação em Química. « Validação de metodologia para determinação de cadaverina e putrecina por LC-MS/MS e aplicação em água como indicador de contaminação por necrochorume / ». reponame:Biblioteca Digital de Teses e Dissertações FURB, 2015. http://www.bc.furb.br/docs/DS/2015/360440_1_1.pdf.
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Orientador: Marcos Rivail da Silva.Co-orientador: Martinho Rau.
Dissertação (Mestrado em Química) - Programa de Pós-Graduação em Química, Centro de Ciências Exatas e Naturais, Universidade Regional de Blumenau, Blumenau.