Fabrication of Phospholipid Bilayer-Coated Microchannels for On-Chip Immunoassays

Anal Chem. 2001 Jan 15;73(2):165-9. doi: 10.1021/ac000997o.

Abstract

Herein we describe a new class of microfluidic immunoassays based upon solid supported lipid bilayers. Two-dimensionally fluid bilayer material, which can accommodate multivalent binding between surface-bound ligands and aqueous receptors, was coated on the surface of poly(dimethylsiloxane) microchannels. The bilayers contained dinitrophenyl (DNP)-conjugated lipids for binding with bivalent anti-DNP antibodies. Twelve independent data points of surface coverage versus bulk protein concentration could be made simultaneously by forming a linear array of channels and flowing fluorescently labeled antibodies into them. This enabled an entire binding curve to be obtained in a single experiment. The measured apparent binding constant for the DNP/anti-DNP system was 1.8 microM. The methodology for performing heterogeneous assays developed here not only produces rapid results but also requires much less protein than traditional procedures and eliminates some standard sources of experimental error.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Immunoassay / instrumentation*
  • Lipid Bilayers
  • Phospholipids / chemistry

Substances

  • Lipid Bilayers
  • Phospholipids