ARGINASE-BASED AMPEROMETRIC BIOSENSOR FOR MANGANESE IONS ANALYSIS

Abstract

The development of simple cost-effective sensitive enzymatic methods for analysis of toxic metallic ions is an actual problem. Promising tools for elaboration of such methods are Mn2+-dependent enzymes. A novel manganese(II)-sensitive amperometric bi-enzyme biosensor based on of recombinant human arginase I (arginase) isolated from the gene-engineered strain of methylotrophic yeast Hansenula polymorpha and commercial urease is described. The biosensing layer with urease and apo-enzyme of arginase was placed onto a polyaniline-Nafion composite platinum electrode. The developed sensor revealed a high sensitivity to Mn2+-ions – 9200±20 A/(M∙m2)with the apparent Michaelis-Menten constant derived from Mn2+-ions calibration curve of 11.5±1.0 µM. A linear concentration range was observed from 1 µM to 6,5 µM MnCl2, a limit of detection being of 0.15 µM and a response time – 2.5 min. The proposed biosensor may be useful to monitor manganese compounds in laboratories of medicine, food industry and environmental control service.