Capillary electrochromatography electrochromatographic separations

Bedalr, M., and El Rassl, Z. (2003). Capillary electrochromatography with monolithic stationary phases III. Evaluation of the electrochromatographic retention of neutral and charged solutes on cationic stearyl-acrylate monoliths and the separation of water-soluble proteins and membrane proteins. /. Chromatogr. A 1013, 47-56. 

Zeng used a silica monolith modified with the liquid crystalline crown ether 29 as a column material in capillary electrochromatography (Scheme 17) [50]. Polycyclic aromatic compounds, benzenediols, pesticides, and steroids were successfully separated on the column. Introduction of the liquid crystalline crown ether led to a significant improve of the electrochromatographic performance. 

Figure 5.14 Electrochromatographic separation of neutral molecules on a 230 mm x 50 mm I.D. capillary packed with 3 mm Hypersil ODS. (A) Capillary electrochromatography, applied voltage 23 kV, (B) micro-HPLC, pressure 130 bar. Peaks, in order of elution, represent thiourea, benzylalcohol, benzaldehyde, benzene, and naphthalene. (Reprinted from Ref. 38 with permission.)...

Capillary electrochromatography based on molecular imprinting 16.4.2 Electrochromatographic separations... 

Capillary electrochromatography-electrospray ionization-mass spectrometry (CEC-ESI-MS) is an analytical technique combining electrochromatographic separation and mass spectrometric detection with an electrospray... 

Later, the same group developed what they call a hybrid microdevice as an alternative to quartz microchips. This device consisted of a short, fiised-sihca capillary column containing a 2.8-cm long polymer gel prepared from acrylamide, 2-acrylamido-2-methyl-l-propanesulfonic acid (AMPS), and allyl- -cyclodextrin as crosslinker. This capillary was set in a groove on a polyvinyl chloride support plate that included sample reservoirs, electrodes, and a sht for on-tube UV-detection. In addition, a ball lens was mounted beneath the detection sht to focus the UV beam. Gel electrophoresis and electrochromatography were then performed in this system. For example, several alkyl phenones were separated in the electrochromatographic mode in less than 200 s. The suggested separation mechanism was related to interactions between the hydrophobie cavity of the P-eyelodextrin and the analytes. However, no direet evidence for this meehanism was presented. 

---