UiO-66/PIM-1 Mixed-Matrix Membrane for Hexane Isomer Separation.

The separation of high-octane dibranched alkanes from naphtha is critical in the refining of gasoline. To date, research on the membrane-based separation of alkane isomers has been limited, with a particular paucity of investigations into mixed-matrix membranes. Herein, the continuous and dense UiO-66/PIM-1 mixed-matrix membrane, which was prepared through precise control of the interfacial structure, was first applied to the differentiation of C6 alkane isomers. Due to the synergistic combination of UiO-66 with differential adsorption capabilities for alkanes and PIM-1 that possesses a cross-linkable structure, the resulting UiO-66/PIM-1-(20) membrane demonstrated remarkable separation performance and high stability. Pervaporation measurements showed that the mass fraction of 2,2-dimethylbutane in the feed side was increased from 50.0 to 75.8 wt % while an excellent flux of 1700 g m-2 h-1 was maintained over a continuous 40 h period. The UiO-66/PIM-1-(20) membrane, characterized by its facile replication and processing, shows potential for large-scale fabrication. This study offers a new approach to the membrane separation of alkane isomers.

An LC-MS/MS method for the simultaneous determination of lycorine and galanthamine in rat plasma and its application to pharmacokinetic study of Lycoris radiata extract in rats.

A rapid, sensitive, and selective liquid chromatography-tandem mass spectrometry was developed for the simultaneous determination of lycorine and galanthamine, two major constituents in Lycoris radiata extract, in rat plasma. Liquid-liquid extraction with ethyl ether was carried out using diphenhydramine as the internal standard. The two bioactive alkaloids were separated on a Zorbax SB-C18 reserved-phase column (150 mm × 4.6 mm, i.d., 5 µm) by gradient elution using a mobile phase consisting of methanol with 0.1% formic acid (A) and water with 0.1% formic acid (B) at a flow rate of 0.6 mL/min. All analytes showed good linearity over a wide concentration range (r (2)>0.99) and the lower limit of quantification was 3.00 ng/mL for each analyte. The average extraction recovery of the analytes from rat plasma was more than 82.15%, and the intra-day and inter-day accuracy and precision of the assay were less than 12.6%. The validated method was successfully applied to monitoring the concentrations and pharmacokinetic studies of two Amaryllidaceous alkaloids in rat plasma after an oral administration of Lycoris radiata extract.