Biosensing in microfluidic channels using Fluorescence Polarization

摘要

Microfabricated microfluidic devices provide useful platforms for sensing and conducting immunoassays for high throughput screening and drug discovery. Here, Fluorescence Polarization has been used as a technique for probing binding events within 500 micron and smaller microfluidic channels fabricated in poly (dimethyl siloxane) (PDMS). The binding of concanavalin A to a lectin-dextran and a glycoprotein-acetylcholinesterase has been used to demonstrate the homogeneous, ratioing format of fluorescence polarization for the quick and accurate determination of extremely low (nanomole) concentrations. Polarization has also been used to sense for a poly-aromatic hydrocarbon (PAH) within a microfluidic channel using binding to an antibody. We have also demonstrated a simple pH sensor based on the change in anisotropy of a pH sensitive fluorophore. The ease of fabrication and measurement using such polarization-based devices make them extremely suitable for micro-sized sensors, assays and total analysis systems.