UV Longitudinal cell design with enhanced sensitivity for capillary electrophoresis

✍ Scribed by Francis I. Onuska; Ken A. Terry

• Publisher: John Wiley and Sons
• Year: 1993
• Tongue: English
• Weight: 425 KB
• Volume: 5
• Category: Article
• ISSN: 1040-7685
• DOI: 10.1002/mcs.1220050310

✦ Synopsis

Abstract

A UV‐absorbance cell assembly for use in capillary zone electrophoresis, or in micellar electrokinetic chromatography, employing a perpendicular variable path length U‐shaped cell of nl volume instead of conventional on‐column detection is described. The length of the optical path can be chosen arbitrarily, regardless of capillary diameter. The extracolumn variance has been overcome through the elimination of connectors between the capillary and the detection system. The technique is demonstrated by means of micellar electrokinetic chromatography for phenols, in which path lengths of up to 4 mm can be tolerated without serious loss of separation efficiency. An efficiency of approximately 130,000 plates m^−1^ for a mixture of phenols using a cell of 50 μm in diameter and an optical path of 4 mm was obtained. This leads to a considerable increase in absorbance signal as compared with the usual on‐column UV‐absorption cell. Construction details are provided.