Non-enzymatic disposable test strip for detecting uric acid in whole blood

A non-enzymatic disposable uric acid test strip based on water-soluble electron-transfer mediator was developed. The test strip comprises electric insulating substrate, conducting film, and a screen printed integrated reagent/blood separation layer. The integrated layer formulation is screen printed over two conductive carbon elements to form a working electrode and a dual-purpose reference/counter electrode. On rehydration, this integrated layer does not break up, but swells to form a gelled reaction zone in the vicinity of the underlying conductive film in which reactants and mediator move freely within this zone, but interfering species such as blood cells are excluded because the filler forms a three-dimensional network on the surface of the conductive elements. At the same time, the separation layer preferably maintains a rate of permeation of the analyte through the integrated reagent/blood separation layer. The excellent reagent/blood separation layer result in good characteristics such as low potential (0.4 V) detection of uric acid with a large determination range from 1.0 to 15 mg/dL uric acid in whole blood, a short response time (within 10 s) and anti-interfering ability. In addition, the test strip can be easily made, particularly mass-produced, and is suitable for household use.