Synthesis of bio-doped oxides for urea sensing

This paper reports on the synthesis of bio-composite oxide thin films intended for use as urea biosensors. The encapsulation of urease molecules in the inorganic matrix of sol-gel processed molybdenum trioxide and the retention of the enzyme´s activity is demonstrated. This is an important step towards the development of resistive bio-detectors where the gas sensitive matrix measures the products of the biochemical reaction (gaseous ammonia) of the hydrolysis of urea by urease.