ABSTRACT
A sensitive chemiluminescence（CL） method was developed for determining melamine in urine and plasma samples based on the fact that melamine can remarkably enhance the chemiluminescence of Luminol-K3 Fe（CN）6 system in alkaline medium. The determination conditions were optimized. Under optimum conditions, the chemiluminescence intensity had a good linear relationship with melamine in the range of 9.0 × 10
ABSTRACT
A novel high performance liquid chromatographic method was developed for the determination of 4-O- methylhonokiol in rabbit plasma and was applied to its pharmacokinetic investigation. Plasma samples were treated by one-fold volume of methanol and acetonitrile to remove the interference proteins. A reverse phase column of SHIM- PACK VP-ODS （150 mm ×4.6 mm, 5.0 μm） was used to separate 4-O-methylhonokiol in the plasma samples. The detection limit of 4-O-methylhonokiol was 0.2 μg/L and the linear range was 0. 012 - 1. 536 mg/L. The good extraction recoveries were obtained for the spiked samples （84.7%, 89.3% and 87.7% for low, middle and high concentrations of added standards, respectively）. The relative standard deviation of intra-day and inter-day precisions was in the range from 0.6% to 13.5%. The pharmacokinetic study of 4-O-methylhonokiol was made and the results from the plasmaconcentration curve of 4-0-methylhonokiol showed a two-apartment open model. This work developed a sensitive, stable and rapid HPLC method for the determination of 4-O-methylhonokiol and the developed method has been successfully applied to a pharmacokinetic study of 4-O-methylhonokiol.
ABSTRACT
A sensitive chemiluminescence(CL) method was developed for determining melamine in urine and plasma samples based on the fact that melamine can remarkably enhance the chemiluminescence of Luminol-K3 Fe(CN)6 system in alkaline medium.The determination conditions were optimized.Under optimum conditions,the chemiluminescence intensity had a good linear relationship with melamine in the range of 9.0 × 10 97.0 × 10 6 g/mL with a correlation coefficient of 0.9992.The detection limits (3σ) were 3.54 ng/mL for urine sample and 6.58 ng/mL for plasma sample.The average recoveries of melamine were 102.6％ for urine sample and 95.1％ for plasma sample.Melamine in samples was extracted with liquid-liquid extraction procedures and the assay results coincided very well with that determined with flow injection chemiluminescence method.The method provides a reproducible and stable approach for sensitive detection and quantification of melamine in urine and plasma samples.
ABSTRACT
A novel high performance liquid chromatographic method was developed for the determination of 4-O-methylhonokiol in rabbit plasma and was applied to its pharmacokinetic investigation.Plasma samples were treated by one-fold volume of methanol and acetonitrile to remove the interference proteins.A reverse phase column of SHIMPACK VP-ODS (150 mm× 4.6 mm,5.0 μm) was used to separate 4-O-methylhonokiol in the plasma samples.The detection limit of 4-O-methylhonokiol was 0.2 μg/L and the linear range was 0.012- 1.536 mg/L.The good extraction recoveries were obtained for the spiked samples (84.7％,89.3％ and 87.7％ for low,middle and high concentrations of added standards,respectively).The relative standard deviation of intra-day and inter-day precisions was in the range from 0.6％ to 13.5％.The pharmacokinetic study of 4-O-methylhonokiol was made and the results from the plasmaconcentration curve of 4-O-methylhonokiol showed a two-apartment open model.This work developed a sensitive,stable and rapid HPLC method for the determination of 4-O-methylhonokiol and the developed method has been successfully applied to a pharmacokinetic study of 4-O-methylhonokiol.