Modification of poly(dimethylsiloxane) channels with hydrophobin for peptide and Protein Analysis — ASN Events
  1. Schedule
  2. Poster Session 2
  3. Modification of poly(dimethylsiloxane) channels with hydrophobin for peptide and Protein Analysis

Modification of poly(dimethylsiloxane) channels with hydrophobin for peptide and Protein Analysis (#224)

Chao Liu 1 , Zhiqi Zhang 1 2 , Fuquan Dang 1 2
  1. Shaanxi Normal University, Xian, 710062, China
  2. Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province, Xian, 710062, China

Microfluidic chips fabricated from polymers exhibit great potential in biological and chemical analyses [1–2]. Poly(dimethylsiloxane) (PDMS) is one of the most commonly used materials for building microfluidic chips in laboratory mainly due to its easy fabrication, good optical transparency, easy sealing with other materials, and good bio-compatibility. However, the surface of PDMS is quite hydrophobic and not compatible with aqueous media, causing poor separation performance due to serious analyte adsorption on the surface and unstable electroosmotic flow (EOF) in microchannels. Thus, surface modification is a critical issue for PDMS microfluidic devices in electrophoresis application. Various approaches for either chemical or physical modification of polymer surfaces are reported to minimize analyte-wall interactions and EOF in microchannels. Dynamic coating with various surface modifiers such as water-soluble polymers, surfactants, and nano-materials represents the most simple and convenient surface modification technique for polymer microchips. So far, dynamic coating has shown very limited success in analysis of peptides and proteins. In the present work, a hybrid dynamic coating using a hydrophobin, SC3, and methyl cellulose (MC) has been developed for suppression of analyte adsorption and EOF in a PDMS channel. The 0.5～1mg/mL SC3 in the running buffer was found to obviously minimize the nonspecific adsorption of analytes such as FITC-labeled BSA in a PDMS channel, while 0.05% MC efficiently suppress was found to efficiently improve the surface hydrophilicity and thus suppress the generation of bubbles. High-performance separation of the FITC-lebled α-lactalbumin, β-lactoglobulin, and lysozyme were achieved 2.06×105, 2.14×105, 1.32×105 plates/m, respectively. We propose that SC3 is a promising surface modifier for PDMS polymer microfluidic chips.

Acknowledgements: The present work is supported by the the National Natural Science Foundation of China (21175088)

References:
1. Dang, F., Tabata, O., Kurkawa, M., Nakajima, K., kazuaki, K., Ishikawa, M., Baba, Y. Anal. Chem. 2006, 78, 1452-1458.
2. Wang, J., Xu, J., Chen, H. J. Chromatogr. A 2006, 1107, 257–2641.