Technology: Blood tester scoops invention award

日期:2019-03-03 01:08:04 作者:巢两 阅读:

By ELISABETH GEAKE A cheap diverse as the presence of HIV antibodies and pregnancy has beaten off 4100 other inventions to win the fourth Toshiba Year of Invention competition. The results of the competition were announced this week. A team of chemists and engineers, led by Roger Bunce and Gary Thorpe at the University of Birmingham’s Wolfson laboratory, took two years to develop the tester and have won £15 000 and a trip to Japan. The printed liquidic circuit (PLC) is simply a piece of filter paper or nylon membrane with wax lines printed on it which act as channels a few millimetres wide to guide water in certain directions. Standard analytical chemicals, used in immunoassay, are also printed on it. A drop of the blood or urine sample is placed at the top of the filter paper, and the bottom dipped in water. The water wicks up, reconstitutes the chemicals and delivers them to the sample where a reaction, and often a colour change, occurs. It analyses samples in a few minutes. One form of the PLC (see Diagram) tests the sample with two chemicals. The chemical closest to the sample is picked up by water which has travelled through two fairly straight channels, so it arrives at the sample quickly. The water for the second chemical takes a slow, winding path. There is even time, before the second chemical arrives, for fresh water to be drawn through the straighter channels and rinse away the unreacted sample left after the first chemical. Bunce says PLCs can test for cholesterol levels, malaria, or mastitis in cows, and could also act as food, soil and environmental testers. The British Technology Group, which is being privatised, has applied for three patents for the PLC, and several major companies are considering licences. The small business category of the awards was won by a fire escape lighting system which is visible through thick smoke. Developed by Brian Perry, an architect, the system guides light from a remote central source along tunnels to show people the quickest way to an exit in an emergency. The light is routed by optical fibres and waveguides, portions of it are diverted with beamsplitters to provide illumination and it can be rerouted to guide people to the best exit. The light is almost invisible under normal conditions,