The Experts below are selected from a list of 156 Experts worldwide ranked by ideXlab platform
Jeanphilippe Croue - One of the best experts on this subject based on the ideXlab platform.
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photodegradation of Sulfathiazole under simulated sunlight kinetics photo induced structural rearrangement and antimicrobial activities of photoproducts
Water Research, 2017Co-Authors: Xizhi Niu, Julie Gladycroue, Jeanphilippe CroueAbstract:Abstract Photolysis is a core natural process impacting the fate of some sulfonamide antibiotics in sunlit waters. In this study, sunlight-induced phototransformation of Sulfathiazole was investigated. A photolytic quantum yield of 0.079 was obtained in buffered water (pH = 8.0). Different natural organic matter isolates inhibited the photolysis of Sulfathiazole by light screening effect. A kinetic model was developed to predict the photodegradation rate of Sulfathiazole using the light screening correction factor of the water matrix in the wavelength range of 300–350 nm. An isomeric photoproduct of Sulfathiazole with a longer retention time was observed on liquid chromatography. Based on its MS/MS spectra and absorption characteristics, the isomer was postulated as 2-imino-3-( p -aminobenzenesulfinyl-oxy)-thiazole. A reaction mechanism for the photo-cleavage and photo-induced structural rearrangement was proposed. The formation mechanism of the isomer was supported by photochemical experiments spiking synthetic 2-aminothiazole; while the formation kinetics were treated with a partly-diffusion-controlled model. The three identified products showed significantly enhanced photo-stability. Antimicrobial assay of irradiated Sulfathiazole solutions with Escherichia coli indicated little antimicrobial potency ascribed to photoproducts. This study demonstrates the efficacy of sunlight in rapidly degrading Sulfathiazole at a predictable rate, leading to photoproducts of low antimicrobial potency. The mass spectrometry and mechanistic work described here are new insights into the photochemistry of sulfonamides.
Tu Lee - One of the best experts on this subject based on the ideXlab platform.
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Intensified Crystallization Processes for 1:1 Drug–Drug Cocrystals of Sulfathiazole–Theophylline, and Sulfathiazole–Sulfanilamide
Crystal Growth & Design, 2018Co-Authors: Kuan Lin Yeh, Tu LeeAbstract:The chemical synthesis and crystallization steps were integrated successfully for directly producing a 1:1 cocrystal of Sulfathiazole–theophylline and a 1:1 cocrystal of Sulfathiazole–sulfanilamide. The benefits of this process intensification were the reduction of number of steps, and the amount of energy consumption and solvent used. In addition, the overall cocrystal yields by Intensified Method I were much higher than the ones by the conventional method. Intensified Method I also gave high-purity cocrystals of ≥99%. Sulfathiazole not forming cocrystals with sulfanilamide by Intensified Method I was dissolved in the mother liquor by taking advantage of the pH-dependent solubility of Sulfathiazole. Cocrystals of both Sulfathiazole–theophylline and Sulfathiazole–sulfanilamide systems remained stable under conditions of 40 °C and 75% relative humidity for a month.
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Intensified Crystallization Processes for 1:1 Drug–Drug Cocrystals of Sulfathiazole–Theophylline, and Sulfathiazole–Sulfanilamide
2018Co-Authors: Kuan Lin Yeh, Tu LeeAbstract:The chemical synthesis and crystallization steps were integrated successfully for directly producing a 1:1 cocrystal of Sulfathiazole–theophylline and a 1:1 cocrystal of Sulfathiazole–sulfanilamide. The benefits of this process intensification were the reduction of number of steps, and the amount of energy consumption and solvent used. In addition, the overall cocrystal yields by Intensified Method I were much higher than the ones by the conventional method. Intensified Method I also gave high-purity cocrystals of ≥99%. Sulfathiazole not forming cocrystals with sulfanilamide by Intensified Method I was dissolved in the mother liquor by taking advantage of the pH-dependent solubility of Sulfathiazole. Cocrystals of both Sulfathiazole–theophylline and Sulfathiazole–sulfanilamide systems remained stable under conditions of 40 °C and 75% relative humidity for a month
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Polymorph farming of acetaminophen and Sulfathiazole on a chip.
Pharmaceutical research, 2006Co-Authors: Tu Lee, Shi Ting Hung, Chung Shin KuoAbstract:Purpose The aim of this paper is to understand at a given temperature (1) the role of template films, the droplet volume of a saturated Sulfathiazole aqueous solution and the solvent on polymorph screening of Sulfathiazole on a silicon wafer, and (2) the effect of template films on the acetaminophen crystal face at the template-crystal interface.
Xizhi Niu - One of the best experts on this subject based on the ideXlab platform.
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photodegradation of Sulfathiazole under simulated sunlight kinetics photo induced structural rearrangement and antimicrobial activities of photoproducts
Water Research, 2017Co-Authors: Xizhi Niu, Julie Gladycroue, Jeanphilippe CroueAbstract:Abstract Photolysis is a core natural process impacting the fate of some sulfonamide antibiotics in sunlit waters. In this study, sunlight-induced phototransformation of Sulfathiazole was investigated. A photolytic quantum yield of 0.079 was obtained in buffered water (pH = 8.0). Different natural organic matter isolates inhibited the photolysis of Sulfathiazole by light screening effect. A kinetic model was developed to predict the photodegradation rate of Sulfathiazole using the light screening correction factor of the water matrix in the wavelength range of 300–350 nm. An isomeric photoproduct of Sulfathiazole with a longer retention time was observed on liquid chromatography. Based on its MS/MS spectra and absorption characteristics, the isomer was postulated as 2-imino-3-( p -aminobenzenesulfinyl-oxy)-thiazole. A reaction mechanism for the photo-cleavage and photo-induced structural rearrangement was proposed. The formation mechanism of the isomer was supported by photochemical experiments spiking synthetic 2-aminothiazole; while the formation kinetics were treated with a partly-diffusion-controlled model. The three identified products showed significantly enhanced photo-stability. Antimicrobial assay of irradiated Sulfathiazole solutions with Escherichia coli indicated little antimicrobial potency ascribed to photoproducts. This study demonstrates the efficacy of sunlight in rapidly degrading Sulfathiazole at a predictable rate, leading to photoproducts of low antimicrobial potency. The mass spectrometry and mechanistic work described here are new insights into the photochemistry of sulfonamides.
Maria Jose Ayoracanada - One of the best experts on this subject based on the ideXlab platform.
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pharmaceutical powders analysis using ft raman spectrometry simultaneous determination of Sulfathiazole and sulfanilamide
Talanta, 2008Co-Authors: Macarena Lopezsanchez, Maria Jose Ruedasrama, A Ruizmedina, Antonio Molinadiaz, Maria Jose AyoracanadaAbstract:Abstract A procedure for rapid quantitative analysis of pharmaceutical powders is described. Powdered samples were measured in a rotating cell in order to avoid sub-sampling problems by increasing the irradiated area. Quantitative determination of Sulfathiazole and sulfanilamide, using a simple univariate calibration model is proposed. Even though both antibacterials are of the same chemical family (sulfonamides), the richness of structural information contained in the Raman spectra allowed their determination using the area of two selected bands (1255 and 1629 cm−1 for Sulfathiazole and sulfanilamide, respectively). Relative standard deviation (R.S.D.) values (n = 10) of 3.35% and 3.46% for Sulfathiazole and sulfanilamide, respectively, demonstrate the good reproducibility of the measurement technique with the rotating cell. The method was successfully applied to the analysis of synthetic mixtures and commercial pharmaceutical powders. The procedure is suitable to be applied to pharmacopoeial uniformity of content testing of batches.
Vernon J. Feil - One of the best experts on this subject based on the ideXlab platform.
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Disposition of Oral [14C]Sulfathiazole in Swine
Journal of Agricultural and Food Chemistry, 1995Co-Authors: Peter W. Aschbacher, C. Struble, Vernon J. FeilAbstract:Disposition of oral Sulfathiazole was studied in swine. Pigs were slaughtered 6, 12, 24, and 48 h after an oral dose of [ 14 C]Sulfathiazole (two at each time period). Excretion of 14 C was rapid (>90% in 48 h), primarily via the urine. Metabolites isolated and characterized by 1 H NMR and FAB MS were N 4 -acetylSulfathiazole from urine, kidney, liver, blood, and muscle ; N 4 -glucoside of Sulfathiazole from muscle ; and an apparent diconjugate from liver, a glucuronide of N4-acetylSulfathiazole. Quantitation was accomplished by HPLC analysis of samples (extracts of tissue and urine) spiked with the reference compounds. Peaks corresponding to the retention time of the reference compounds were trapped and assayed for 14 C. Sulfathiazole and N4-acetylSulfathiazole were the principal 14 C-labeled compounds in urine and kidney. If present, the glucoside or glucuronide represented
