Differentiation of green tea samples by chiral CD-MEKC analysis of catechins content.

A chiral CD-MEKC method, enantioselective for catechin and gallocatechin, was developed, validated and applied to the analysis of tea samples. The method was addressed to the fast and simultaneous quantitation of the most represented and biologically important green tea catechins and methylxanthines. The CD-MEKC was based on SDS as surfactant (90 mM) and hydroxypropyl-beta-CD (25 mM) as chiral selector, under acidic conditions (25 mM borate-phosphate buffer, pH 2.

Controlled release of vancomycin from cross-linked gelatine.

This paper explores the possibility of using biodegradable cross-linked gelatines as antibiotic devices for a long-term elution (80 days). Capillary electrophoresis (CE) has been utilized to evaluate the mass percentage of vancomycin and gelatine contemporary released from differently cross-linked vancomycin loaded gelatine samples in an elution time ranging from 24 to 1920 h. While the solubilization kinetic of gelatine samples differently cross-linked can be very close described by the simplified Higuchi model, the vancomycin release kinetic is contemporary governed by both the Fickian diffusion process trough the gelatine matrix network and the dissolution process of the matrix due to its degradation.