Advances in capillary electro-chromatography / 药物分析学报

Capillary electrochromatography (CEC) is a micro-scale separation technique which is a hybrid between capillary electrophoresis (CE) and liquid chromatography (LC). CEC can be performed in packed, monolithic and open-tubular columns. In recent three years (from 2016 to 2018), enormous attention for CEC has been the development of novel stationary phases. This review mainly covers the development of novel stationary phases for open-tubular and monolithic columns. In particular, some biomaterials attracted increasing interest. There are no significant breakthroughs in technology and principles in CEC. The typical CEC applications, especially chiral separations are described.

Enantioseparation of 38 Racemates on Four Chiral Columns in High Performance Liquid Chromatography / 分析化学

The enantioseparations of 38 racemates on Chiralcel OD, Chiralpak AD, Chiralpak IA and(S, S)-Whelk-01 were presented by HPLC. Those enantiomers come from the amines, alcohols, ethers, ketones, aromatic derivatives, heterocyclic compounds, amide acids and medicines etc. With the mobile phase of n-hexane)/isopropanol(90∶ 10, V/V), n-hexane/isopropanol/trifluoracetic acid(90∶ 10∶ 0.2, V/V) or n-hexane/isopropanol/triethylamine(90∶ 10∶ 0.2, V/V), over 70% enantioseparations were obtained for OD, AD and IA columns). The order of enantioseparation selectivity for four columns was OD>AD>IA>(S,S)-Whelk-01, and among those columns there was a big chiral discriminating complementarity. This investigation was useful for choosing chiral columns to separate chiral compounds.

Síntesis y caratterización de fases estacionaris mesoporosas mediante pruebas cromatográficas y relaciones cuantitativas estructura-retención / Synthesis and characterization of mesoporous stationary phases using chromatographic tests and quantitative structure-retention relatinnships

En este trabajo se describe la síntesis, funcionalización y evaluación cromatográfica de tres sílicas mesoporosas con propiedades fisicoquímicas diferentes. Los materiales son preparados de acuerdo con métodos ya establecidos, que conducen a partículas isomórficas de tamaño micrométrico, y se modifican químicamente mediante un procedimiento clásico de silanización con octildimetilclorosilano seguido por silanización secundaria o end-capping con trimetilclorosilano. La prueba de Galushko y las relaciones cuantitativas estructura retención (RCER) son implementadas para la evaluación cromatográfica. Con el fin de realizar un estudio comparativo, los parámetros obtenidos se confrontan con los reportados en la literatura para cinco columnas comerciales. Aunque el comportamiento cromatográfico es el esperado para fases octil ligadas, los nuevos materiales presentan una mayor hidrofobicidad e inactividad química si se les compara con las columnas tradicionales. La asimetría observada para los picos es atribuida a irregularidades en el empaque debido a una mayor dispersión en el tamaño y la morfología de partícula.

In this work the synthesis, functionalization and chromatographic evaluation of three mesoporous silicas with different physical chemistry properties are described. The materials were prepared, as isomorphic micrometric particles, according to established methods and they were chemically modified by a classic procedure of silylation with octyldimethylchlorosilane followed by secondary silylation or end-capping. Galushko’ s test and quantitative structure-retention relationships were implemented for the chromatographic evaluation. A comparative study was done by comparing the parameters obtained with those reported in literature for five commercial columns. Although the chromatographic behavior is the expected for octyl phases, the new materials show larger hydrophobicity and chemical inactivity when compared with traditional columns. The asymmetric behavior of the peaks is attributed to packing irregularities due to a larger dispersion in particle size and morphology.