Researchers have designed a uric acid sensor trapping uricase enzyme on an epoxy resin membrane1. The battery-powered bedside sensor will be useful to detect varying levels of uric acid in body fluids in ailments such as gout, arthritis, cardiovascular and neurological diseases.

There are various types of uric acid sensors, mostly unstable and time consuming. To devise a smarter uric acid sensor, for the first time the researchers extracted uricase enzyme from 20-day old cowpea leaves. They smeared the enzyme on 'araldite' membrane composed of epoxy resin and tested its efficacy to measure levels of uric acid using serum samples from apparently healthy persons and patients suffering from gout.

The sensor reads samples within 10-12 seconds. The enzyme electrode shows only 32 per cent loss of initial activity after one hundred uses over a period of 60 days. The enzyme is stable when exposed to heat.

"The uric acid biosensor is very simple, sensitive and portable and can be used at the bedside," says lead researcher Chandra Shekhar Pundir from the department of biochemistry of M. D. University, Rohtak, Haryana.