Preconcentration and Separation of Mixed-Species Samples Near a Nano-Junction in a Convergent Microchannel

Sensors

Ping-Hsien Chiu²  Chen-Hsun Weng¹  Ruey-Jen Yang² 

[1] Medical Device Innovation Center, National Cheng Kung University, Tainan 70101, Taiwan;Department of Engineering Science, National Cheng Kung University, Tainan 70101, Taiwan;

关键词: microfluidics;    preconcentration;    ion concentration polarization;    electrophoresis;   

DOI  :  10.3390/s151229824

来源: mdpi

【 摘 要 】

A fluidic microchip incorporating a convergent microchannel and a Nafion-nanoporous membrane is proposed for the preconcentration and separation of multi-species samples on a single platform. In the device, sample preconcentration is achieved by means of the ion concentration polarization effect induced at the micro/nano interface under the application of an external electric field, while species separation is achieved by exploiting the different electrophoretic mobilities of the sample components. The experimental results show that the device is capable of detecting C-reactive protein (CRP) with an initial concentration as low as 9.50 × 10⁻⁶ mg/L given a sufficient preconcentration time and driving voltage. In addition, it is shown that a mixed-species sample consisting of three negatively-charged components (bovine serum albumin (BSA), tetramethylrhodamine(TAMRA) isothiocyanate-Dextran and fluorescent polymer beads) can be separated and preconcentrated within 20 min given a driving voltage of 100 V across 1 cm microchannel in length. In general, the present results confirm the feasibility of the device for the immunoassay or detection of various multi-species samples under low concentration in the biochemical and biomedical fields. The novel device can therefore improve the detection limit of traditional medical facilities.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.