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1.
J Chromatogr Sci ; 61(1): 96-101, 2022 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-36124845

RESUMO

A green, simple and cost-effective, validated high-performance liquid chromatographic (HPLC) with UV detector has been developed an analytical method for the simultaneous determination of the most significant phenolic compounds viz. Gallic acid (GA), Quercetin (QC) and Ferulic acid (FA). The detection limit of GA, QC, FA was 0.303, 0.168, 0.0976 µg/mL and quantitation limit was 0.918, 0.051, 0.295 µg/mL, respectively. All parameters of planned validated method were carried out as per the ICH guidelines. This analytical method was applied to determine the phenolic compounds in fruits cultivated in India. Phenolic compounds in fruits extract were quantified using regression equations. This method can be scaled up to determine the alkaloids from several medicinal and poisonous plants samples in pharmaceutical, forensics and industrial areas.


Assuntos
Cetomacrogol , Tensoativos , Cetomacrogol/análise , Cromatografia Líquida de Alta Pressão/métodos , Frutas/química , Extratos Vegetais/química , Fenóis/análise , Quercetina/análise , Ácido Gálico/análise
2.
Forensic Sci Res ; 6(1): 19-33, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-34007513

RESUMO

Recently, cloud point extraction (CPE) coupled with back extraction (BE) has been suggested as a promising alternative to liquid-liquid extraction. In CPE, non-ionic surfactants in aqueous solutions form micelles and the solution becomes turbid when heated to the cloud point temperature. Microwave- or ultrasonic-assisted BE can be performed after CPE and before injection of the sample for instrumental analysis by ultraviolet-visible spectroscopy, high-performance liquid chromatography, gas chromatography, gas chromatography-mass spectrometry, or liquid chromatography-mass spectrometry. This article reviews selected published scientific research on the application of CPE-BE to the determination of alkaloids, drugs and organophosphorus compounds from several complex matrices. This method could be scaled-up for use in forensic science.

3.
J Chromatogr B Analyt Technol Biomed Life Sci ; 1074-1075: 129-138, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29396378

RESUMO

A procedure for the determination of Eszopiclone (ESZ) from complex matrices i.e. in vitro (spiked matrices), as well as in vivo (mice model) was developed using cloud point extraction coupled with microwave-assisted back-extraction (CPE-MABE). Analytical measurements have been carried using UV-Visible, HPLC and MS techniques. The proposed method has been validated according to ICH guidelines and legitimate reproducible and reliability of protocol is assessed through intraday and inter-day precision <3.61% and <4.70%, respectively. Limit of detection has been obtained as 0.083µg/mL and 0.472µg/mL respectively, for HPLC and UV-Visible techniques, corresponding to assessed linearity range. The coaservate phase in CPE was back extracted under microwaves exposure, with isooctane at pre-concentration factor ~50 when 5mL of sample solution was pre-concentrated to 0.1mL. Under optimized conditions i.e. Aqueous-Triton X-114 4% (w/v), pH4.0, NaCl 4% (w/v) and equilibrium temperature of 45°C for 20min, average extraction recovery has been obtained between 89.8 and 99.2% and 84.0-99.2% from UV-Visible and HPLC analysis, respectively. The method has been successfully applied to the pharmacokinetic estimation (post intraperitoneal administration) of ESZ in mice. MS analysis precisely depicted the presence of active N­desmethyl zopiclone in impales as well as in mice plasma.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Zopiclona/análise , Espectrometria de Massas/métodos , Animais , Fracionamento Químico , Zopiclona/química , Zopiclona/isolamento & purificação , Zopiclona/farmacocinética , Humanos , Concentração de Íons de Hidrogênio , Limite de Detecção , Modelos Lineares , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Micro-Ondas , Leite/química , Octoxinol , Polietilenoglicóis , Reprodutibilidade dos Testes
4.
Food Chem ; 185: 284-8, 2015 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-25952870

RESUMO

The aim of this study was to enhance the extraction of total phenolic contents (TPC) and antioxidants from fruit juices by the application of surfactants formulations instead of conventional solvents (methanol, ethanol and acetone). A variety of fruit infusions: apple red delicious (apple (rd)) (Malus domestica), Mcintosh apple (apple (i)) (Malus pumila), sweet lemon (Citrus limetta) and mango (Magnifera indica) were studied. Effect of water, organic solvents and five different aqueous surfactant formulations viz. SDS, Brij-35, Brij-58, Triton X-100 and Span-40 were explored for the extraction of TPC and determining the antioxidant activity (AA). The TPC and AA (%) were determined using Folin-Ciocalteu (FCA) and DPPH assay, respectively. The effect of surfactant type, concentration and common organic solvents on the extraction of TPC and AA (%) was studied using UV-visible spectrophotometric technique. Among all the extracting systems employed, Brij-58 showed the highest extraction efficiency.


Assuntos
Antioxidantes/isolamento & purificação , Bebidas/análise , Frutas/química , Fenóis/isolamento & purificação , Tensoativos/química , Antioxidantes/análise , Fenóis/análise , Polietilenoglicóis/química
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