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1.
Luminescence ; 38(3): 269-279, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36657788

RESUMO

High-performance liquid chromatography (HPLC) coupled with a fluorescence detector was used to analyse bioactive phytoconstituent scopoletin from a polyherbal composition derived from the extract prepared from roots of Argyreia nervosa, roots of Withania somnifera, and fruits of Tribulus terrestris. This analytical method was developed as a quality control tool for standardization of the composition to be formulated to enhance spermatogenesis. Chromatographic separation was achieved using Luna® (250 mm × 4.6 mm, 100 Å, 5 µm) C18 column as a stationary phase, and water (0.01 M glacial acetic acid):methanol: acetonitrile (60:20:20, %v/v/v) as the mobile phase; passed through the column at a set flow rate of 1.0 ml min-1 . The elute in the flow cell was excited at 345 nm and the chromatogram was recorded at 444 nm as the emission wavelength. As a part of the analytical Quality by Design approach, systemic studies were conducted to identify potential risks affecting the critical attributes (area, resolution, retention time) of the analytical method, and mitigating the potential risks after optimizing the chromatographic parameters with the help of the Design of Experiment approach. The developed analytical method was subjected to the validation studies, which showed a linear relationship (r2 = 0.9982) between the concentration and the area corresponding to scopoletin peak in the concentration range 10-130 ng ml-1 . The method was found selective, sensitive, and precise. The recovery of the scopoletin was found in a range 99.53-102.13%; confirming the accuracy of the analytical method. The amount of scopoletin was estimated to be 0.146%w/w from the polyherbal composition.


Assuntos
Metanol , Escopoletina , Cromatografia Líquida de Alta Pressão/métodos , Controle de Qualidade , Água
2.
Biomed Chromatogr ; 33(11): e4668, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31353499

RESUMO

Thiamine deficiency, if detected early in infancy, can be treated with thiamine supplementation and can prevent seizures, other disabilities and death. The dried blood spot (DBS) sampling technique is an attractive sample collection technique for infants. The present study reports the development and validation of a highly sensitive and precise method for quantification of thiamine diphosphate from DBS. The method utilizes full-spot analysis of a volumetrically deposited 40 µl DBS. The analyte was extracted from the DBS using 50% methanol and then derivatized using potassium ferricyanide to thiochrome. Separation was achieved with the help of an Inertsil ODS C18 column (5.0 µm, 250 × 4.6 mm) using 150 mm phosphate buffer pH 7-acetonitrile (90:10, % v/v) as the mobile phase. The use of a fluorimetric detector gave a good response to the thiochrome derivative offering good sensitivity for the method. The excitation and emission wavelengths were 367 and 435 nm, respectively. The limit of detection and lower limit of quantification were 5 and 10 ng/ml, respectively. Linearity was demonstrated from 10 to 1000 ng/ml, and precision (CV) was <12.08%, at all tested quality control levels. The method accuracy was 89.34-118.89% with recoveries >80%. Bland-Altman analysis of DBS sampling vs. whole blood demonstrated a mean bias of only 1.16 ng/ml, with a majority of the 60 investigated patient samples lying within 7.2% of the corresponding concentration measured in blood, thereby meeting the clinical desirable biological specification criterion and showing that the two methods are comparable.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Teste em Amostras de Sangue Seco/métodos , Fluorometria/métodos , Deficiência de Tiamina/diagnóstico , Tiamina/sangue , Humanos , Lactente , Recém-Nascido , Limite de Detecção , Modelos Lineares , Reprodutibilidade dos Testes
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