medgadget.com
Paper-based Diagnostic Microfluidic Devices
MIT Technology Review is reporting that researchers at Harvard are using paper as the building block material for creating small microfluidic devices, potentially allowing to make cheap disposable diagnostic tests. A pinprick of blood or drop of urine soaked up at the edge of the Whitesides device moves naturally through the paper, in much the way that wine will spread through a paper napkin. But the paper is treated with a hydrophobic polymer, which directs the liquid along prescribed channels. Once the liquid reaches the wells at the ends of the channels, it interacts with reagents, turning the paper different colors. The colors can be matched to those on a color key, much as they are in a pH test. One test design that looks like a minia...
