Enhancing separation in short‐capillary electrophoresis via pressure‐driven backflow

Abstract

Electrophoresis 2015, 36, 1549–1554. DOI: 10.1002/elps.201500013 Pressure-driven backflow is an attractive method to improve CZE separation resolution via counterbalancing the EOF. In this study, we describe a new method to generate steady backflow in a short capillary via a tapered capillary tip, which can be easily fabricated by heating a straight capillary while stretching it with a constant force. Significant improvement of the CZE separation of AAs is achieved using the tapered capillary with effective separation length of 5 cm. The present method presents good run-to-run repeatability and capillary-to-capillary reproducibility, and has merits in its simple and easy-to-operate design, which could be useful in further miniaturization of the CZE technique.