Towards the Design of an Acetone Breath Biosensor

Abstract

Acetone is one of the most abundant volatile organic compounds (VOC) in human breath and high acetone levels result in ketoacidosis. Many acetone sensors have been developed; however, many disadvantages are present; therefore, there is a need for a more specific, biologically friendly, and simpler biosensor for breath acetone detection for diabetics. This study outlines a procedure for isolation, purification, and characterization of NADPH-dependant carbonyl reductase enzyme for use in an amperometric acetone sensor. Carbonyl reductase was extracted from Saccharomyces pastorianus yeast cells and purified using column chromatography. Carbonyl reductase activity was evaluated using activity assays and was also studied electrochemically. Furthermore, this study outlines a procedure for a flow injection method used for detecting aqueous acetone in the presence of carbonyl reductase. Lastly, various immobilization techniques were tested in order to improve current response and the selectivity towards acetone.