Search

Your search keyword '"Derayea, Sayed M."' showing total 430 results
Start Over Author "Derayea, Sayed M."
430 results on '"Derayea, Sayed M."'

26. Facile nucleophilic substitution approach for the spectrofluorimetric assay of natamycin based on diarylpyrrolone formation, evaluation of method greenness.

Author

Derayea, Sayed M. and Mohammed, Fatma F.

Subjects
*NUCLEOPHILIC substitution reactions, *AQUEOUS humor, *ARTIFICIAL eyes, *EYE drops, *AMINO group
Abstract

An ecofriendly, effective, and selective spectrofluorimetric approach for natamycin analysis was developed using fluorescamine as a fluorogenic probe. Natamycin is the only topical ocular antifungal medication that is presently on the market for treating keratitis, conjunctivitis, and blepharitis caused by yeast and other fungi. Owing to its primary aliphatic amino group, natamycin can easily interact with fluorescamine resulting in the formation of the highly fluorescent diaryl pyrrolone derivative. The derivatization reaction was completed within very short time at room temperature in borate buffer solution (pH 7.6). The fluorescence intensity of the reaction product was monitored at 465 nm after exciting at 390 nm. The linearity range of the spectrofluorimetric method was 0.25–4.0 µg/mL of natamycin with limit of detection (LOD) of 0.082 µg/mL. The method was applied for the determination of the cited drug in pharmaceutical eye drops and artificial aqueous humor with high percentage recoveries and low relative standard deviations. In addition, the involved analytical procedure was green based on the results of the ecology scale scores. [ABSTRACT FROM AUTHOR]

Published
2025
Full Text
View/download PDF

44. Xanthene based resonance Rayleigh scattering and spectrofluorimetric probes for the determination of cyclobenzaprine: Application to content uniformity test

Author

Abdel-Lateef Mohamed A., Almahri Albandary, Derayea Sayed M., and Samir Ebtihal

Subjects
cyclobenzaprine, eosin y, pharmaceutical analysis, resonance rayleigh scattering, spectrofluorimetry, Chemistry, QD1-999
Abstract

In this work, a resonance Rayleigh scattering technique and a spectrofluorimetric technique were applied to the quantification of cyclobenzaprine through two validated methods. The suggested methods are based on a facile association complex formation between cyclobenzaprine and eosin Y reagent in the acidic medium. The resonance Rayleigh scattering method relied on the enhancement in the resonance Rayleigh scattering spectrum of eosin Y at 370 nm after the addition of cyclobenzaprine. On the other hand, the spectrofluorimetric quantification relied on the quenching effect of cyclobenzaprine on the fluorescence strength of the eosin Y reagent at 545 nm (excitation wavelength at 300 nm). The suggested methods were linear over the ranges of 0.07–1.75 μg/mL and 0.15–2.0 μg/mL with detection limit values of 0.023 μg/mL and 0.048 μg/mL for the resonance Rayleigh scattering method and the spectrofluorimetric method, respectively. All reaction conditions for cyclobenzaprine–eosin Y formation were experimentally evaluated and optimized. In addition, both methods were validated based on ICH rules. Furthermore, the developed methods were practically applied to the analysis of cyclobenzaprine in its commercial tablet dosage form with acceptable recoveries. Moreover, the content uniformity test of the commercial cyclobenzaprine tablets was successfully applied using the proposed spectroscopic methods based on USP rules.

Published
2020
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results