Polyvinylsilazane layer coating and its application in poly(dimethylsiloxane) microchip electrophoresis

Abstract

In this paper, reactive polyvinylsilazane (PVSZ) is employed as silicate source for poly(dimethylsiloxane) (PDMS) channel surface modification. The PVSZ submicron layer is simply constructed by flushing 1 wt.% PVSZ-anhydrous DMF solution into PDMS channel for 1 min. After UV and thermal curing, the reactive coating is subjected to hydrolysis reaction in an alkali solution for 1 h to convert the consolidated polymer surface to silicate phase. The surface is characterized by SEM, AFM and contact angle measurement. The PVSZ silicate channel is of optical transparence and solvent resistance, and provides a long-term stable electroosmotic flow (EOF) with 43 +/- 0.1 x 10(-4) cm(2) V-1 s(-1) at pH 9.00, and a reliable capillary electrophoresis (CE) performance. Theoretical plate numbers of five FITC-labeled amino acids were all over 14,000 (2.8 mu m height), and EOF repeatability is much superior to that of PDMS channel. (C) 2013 Elsevier B.V. All rights reserved,