Enantiomer Separation of Acidic Chiral Compounds on a Clarithromycin-Zirconia Hybrid Monolith by Capillary Electrochromatography

Review of recent advances in development and applications of organic-silica hybrid monoliths

Organic-silica hybrid monoliths attracted attention as an alternative to extensively researched organic polymer-based and silica-based counterparts. The development and applications of these materials as extraction and separation media in capillary liquid chromatography and capillary electrochromatography were previously reviewed in several manuscripts. In this review, we will concentrate on work published since mid-2016 focusing on advances in their development using sol-gel chemistry of tetra- and trialkoxysilanes and subsequent surface modification with organic monomers, and "one-pot" strategy incorporating sol-gel chemistry of alkoxysilanes and free-radical polymerization, ring-opening polymerization, or thiol-based click polymerization with organic monomers. Approaches adapted to the preparation of hybrid monoliths made with polyhedral oligomeric silsesquioxanes will be covered as well.

Analytical research on the separation and residue of chiral pesticide triadimenol in fruit and vegetable puree

In this paper, a method for the separation of triadimenol stereoisomers using ultra-performance convergence chromatography and an analytical method for the determination of triadimenol stereoisomer residues in pumpkin puree, apple puree, and tomato puree as a supplement for infants are established. Test samples were extracted with acetonitrile and successively purified with graphitized carbon black and Florisil column. Afterward, Acquity Trefoil AMY1 column was adopted for chiral separation of chromatographic column, and gradient elute was carried out with supercritical carbon dioxide-methanol as the mobile phase and with external standard method for quantitation. Results showed that the linearly dependent coefficient of the four kinds of triadimenol stereoisomers within 1.0 and 50 mg/L was greater than 0.9997, and the limit of quantitation of the four kinds of triadimenol stereoisomers was 0.05 mg/kg. Recovery experiment was carried out within 0.05 and 1.0 mg/kg scope, the recoveries were 81.0-107％, and the relative standard deviation was 2.3-7.6%. This method implemented the separation of triadimenol stereoisomers and its residue test in pumpkin puree, apple puree, and tomato puree as a supplement for infants, and it can provide reliable technical support for the analysis of pesticide residue and assessment of product quality.