A VALVE FOR A MICROFLUIDIC DEVICE

摘要

A valve for controlling fluid flow in a microfluidic device is provided. The valve comprises a chamber (26) formed on a substrate (24), a heating coil (42), and a valve material (30) contained in the chamber (26). When the valve is to be closed, the heating coil is activated causing the valve material to expand out of the chamber, through a neck portion (28), and into the main channel (22), blocking it. Preferably, the valve material is paraffin wax, and is caused to melt by the heating coil (42). On melting the melted paraffin wax flows into the main channel whereupon it cools and solidifies. A restriction (34), with collar (36) provides a cool surface on which the solidifying wax accumulates.