A novel disposable amperometric UA strip

The principle of the signal amplification based on substrate recycling and mediated regeneration of uricase was applied to a novel disposable amperometric uric acid (UA) strip. The sensitivity was much improved over a batch method using dithiothreitol and the detection limit of uric acid was found to be down to 3 × 10−6 mol L−1. Thinking of using electrochemically active electron acceptors (potassium ferricyanide) to which the enzyme can donate electrons, the UA strip can apply an electrode potential as low as possible to eliminate the interference. This chemically amplified system is very useful for the direct assay of uric acid in whole blood without complicated pretreatment of the samples, because this sensor has the potential to detect the excellent sensitivity and selectivity. Good correlation was observed between this strip and conventional spectrophotometry.