High yield sample preconcentration using a highly ion-conductive charge-selective polymer

Honggu Chun, Taek Dong Chung, J. Michael Ramsey

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The development and analysis of a microfluidic sample preconcentration system using a highly ion-conductive charge-selective polymer [poly-AMPS (2-acrylamido-2-methyl-1-propanesulfonic acid)] is reported. The preconcentration is based on the phenomenon of concentration polarization which develops at the boundaries of the poly-AMPS with buffer solutions. A negatively charged polymer, poly-AMPS, positioned between two microchannels efficiently extracts cations through its large cross section, resulting in efficient anion sample preconcentration. The present work includes the development of a robust polymer that is stable over a wide range of buffers with varying chemical compositions. The sample preconcentration effect remains linear to over 3 mM (0.15 pmol) and 500 μM (15 fmol) for fluorescein and TRITC-tagged albumin solutions, respectively. The system can potentially be used for concentrating proteins on microfluidic devices with subsequent analysis for proteomic applications.

Original languageEnglish
Pages (from-to)6287-6292
Number of pages6
JournalAnalytical Chemistry
Issue number14
Publication statusPublished - 2010 Jul 15
Externally publishedYes


ASJC Scopus subject areas

  • Analytical Chemistry

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