Disposable uric acid biosensor by bacterial crude uricase enzyme modified screen printed electrode

Abstract

Biosensor Laboratory, Department of Polymer Science and Technology, University of Calcutta, 92, Acharya Prafulla Chandra Road, Kolkata-700 009, India E-mail : [email protected] Biosensors and Bioelectronics, Linköping University, SE-581 83 Linköping, Sweden Manuscript received online 27 January 2014, accepted 31 July 2014 Uric acid is the primary end product from purine derivatives in human metabolism. Excessive production of uric acid may lead to gout, hyperuricemia and kidney disorder. Different analytical methods for uric acid such as colorimetry, commercial enzyme electrode and commercially available uric acid kit are used widely. The main purpose of this research was to develop a screen printed electrode based uric acid biosensor using gelatin immobilized uricase enzyme extracted from Comamonas sp. BTUA. The enzyme catalyzed oxidation of uric acid in presence of oxygen, producing allantoin and hydrogen peroxide. The linearity of the standard curve in the concentration ranges from 5.94 × 10^–6 to 4.75 × 10^–4 molar was satisfactory and could be used for the quantitative determination of uric acid in human serum samples. The limit of detection (LOD) was 2.26 µM and sensitivity was evaluated as 3.31 nA µM^–1 of uric acid. One modified electrode could be used for six measurements with 95% accuracy up to 25 days. The developed biosensor was easy to use, inexpensive, sensitive and reliable.