Isothermal Biochemical Amplification in Miniaturized Reactors with Integrated Microvalves

Abstract

A microreactor of 64 nl volume with integrated micro membrane valves of 1.7 mm² active area was designed for examination of biochemical reaction diffusion systems. The goal was to create a reactor with integrated flow control to improve the system response by reducing delay times from minutes to seconds compared to the use of micro syringe pumps for fluid control. To demonstrate the functionality of this microsystem a cooperatively coupled amplification system (CATCH) [1] was run in the reactor. The course of the reaction was observed by CCD imaging using an intercalating dye which monitors the concentration of the amplified double stranded DNA molecules.

The microvalves allow actively switchable mixing of the reactants at the entrance to the reactor and the regulation of the flow rates. The reactor also demonstrates switchable inoculation of the amplification mixes with DNA template and a spatially resolved course of the reaction by fluorescence imaging.