Analytical Sciences

Abstract − Analytical Sciences, 30(12), 1151 (2014).

A Miniaturized Transverse Flow Gating Interface for the On-line Coupling of Solid-phase Extraction with Capillary Electrophoresis
Xintong LI, Lianjuan FU, Qianfeng WENG, and Jinxiang LI
Department of Chemistry, Liaoning Normal University, 850 Huanghe Road, Dalian 116029, P. R. China
A miniaturized transverse flow gating interface (μ-TFGI) is presented for the on-line coupling of solid-phase extraction with capillary electrophoresis (SPE-CE). The fabrication and operation procedures of the μ-TFGI are described in detail. After the operation conditions were investigated and selected, the μ-TFGI was evaluated on an SPE-CE-UV setup using clenbuterol (CLB) as the test analyte. The preconcentration factors obtained with the SPE-CE-UV system and the SPE-UV part were 600 and 620, respectively. The plate numbers obtained within 3 min were 100000 and 80000 for automatic injection via the μ-TFGI and manual direct injection, respectively. The precisions were 2.4 – 6.8% (RSD, %, n = 9) and 3.1% (RSD, %, n = 27) for the recovery (94.3 – 101.9%) and migration time of CLB spiked in urine samples, respectively. These results demonstrate that the μ-TFGI has the ability to exactly and reproducibly transfer nanoliters of fractions from SPE onto CE with no degradation of the efficiencies of SPE and CE.