a simple and reproducible hplc method with spectrophotometric detection was developed for determination of rivastigmine in human plasma. liquid-liquid extraction of rivastigmine and donepezil (as internal standard) from plasma samples was performed with 1-butanol/n-hexane (2:98 v/v) in alkaline condition followed by back-extraction into diluted acetic acid. chromatography was carried out using ...

water contamination due to the wide variety of pesticides used in agriculture is a global environmental pollution problem. in order to reach at sub-î¼gl-1 levels of detection, an efficient extraction technique is required. a simple, fast and economical method, dispersive liquid-liquid micro extraction (dllme), followed by gas chromatography-mass spectrometry was assessed for determining endosul...

A simple and reproducible HPLC method with spectrophotometric detection was developed for determination of rivastigmine in human plasma. Liquid-liquid extraction of rivastigmine and donepezil (as internal standard) from plasma samples was performed with 1-butanol/n-hexane (2:98 v/v) in alkaline condition followed by back-extraction into diluted acetic acid. Chromatography was carried out using ...

recently, 6-(2-naphthyl)-2, 3-dihydro-as-triazine-3-thione (ndtt) was synthesized in laboratory and used successfully for the spectrophotometric determination of nanogram levels of cu2+ in aqueous solution. this reagent forms a specific red complex with cu2+ ions after the extraction by chloroform at alkaline ph. the absorption of the complex in the uv region (313 nm) is about 8 times as strong...

A simple and reproducible HPLC method with spectrophotometric detection was developed for determination of rivastigmine in human plasma. Liquid-liquid extraction of rivastigmine and donepezil (as internal standard) from plasma samples was performed with 1-butanol/n-hexane (2:98 v/v) in alkaline condition followed by back-extraction into diluted acetic acid. Chromatography was carried out using ...

this paper deals with the extraction of l-theanine containing aliquat 336 as a carrier and cyclohexane as solvent across bulk liquid membrane. the optimum operation condition are as follows: extraction time of 150 min, initial concentration of theanine in the feed phase is 1.8 g/l, the carrier concentration is 0.5 m, the ion of the receiving phase is 0.2 m nacl of na2hpo4-nah2po4 buffer solutio...

abstractbackground and objective: microwave-assisted extraction (mae) is one of the novel, fast, and efficient methods for extraction of bioactive compounds. the aim of this study was optimization of mae of betalains from red beet (beta vulgaris) and evaluating antioxidant activity of its methanolic extract.materials and methods: the effects of independent variables namely, microwave power leve...

in this study, liquid-liquid extraction process in a kuhni extraction column was modeled and simulated. a non-equilibrium dynamic model was developed for modeling liquid-liquid extraction processes based on a rate-based model. the model equations are inclusive of partial and ordinary differential equations which were discretized in column height direction. the population balance model was used ...