Optical and impedance detection of DNA hybridisation using barcoded micro-particles in a microfluidic device

摘要

Micron-sized polymer particles are commonly used in chemistry as substrates for attaching proteins and DNA. The analysis of such particles is important for a wide variety of biochemical assays. One area of particular interest is the development of encoded or barcoded particles. The use of such particles allows for the realization of a number of novel combinatorial chemistry processes and multi-analyte assays. In this paper we describe a microfluidic device for the analysis of microfabricated barcoded particles. This allows specific particles to be identified by their optical diffraction pattern as they pass through a flow channel in a microfluidic device. The device also has optical (fluorescence and diffraction) and broadband impedance measurement capabilities allowing the full characterization of the encoded particles as they pass through the device. Barcodes are fabricated from the SU8 photo-epoxy using standard photolithographic techniques. DNA chemistry is performed on these particles. In this paper we present data showing the ability of the system to detect DNA hybridization on the surface of polymer beads.