Polymer and electrocatalytic membranes for improved selectivity of glucose biosensor

Abstract

In the last decades research in the sphere of biosensors concentrates on the invention of wearable devices that would give an opportunity to patients to perform necessary analysis in vivo painlessly, easily, and effectively. The glucose biosensor is one of such devices that allows people with diabetes to monitor rapidly changing glucose level in whole blood. Though, utilising instruments recently available in the market can be difficult and painful because of blood sampling. Therefore, the aim of the recent research is to come up with a non-invasive technique for glucose detection in human body preferably in a wearable device set. Consequently, the configuration of the glucose biosensor needs to be optimised to enable on-body measurements. A major part of studies in the field of amperometric glucose biosensors is focused on the eliminating of other oxidisable species than glucose from the surface of the electrode. However, little research has been done in the evaluation of their influence on current response in a real sample, which is always a complex mixture of measurable glucose and several other components, among which ascorbic acid is the most abundant. In this work, the analytical performance of glucose biosensors has been tested towards additions of both aliquots of pure glucose and a mixture of glucose with ascorbic acid. The influence of ascorbic acid on the current response corresponding to glucose concentration has been determined based on the comparison with the response obtained with the pure glucose solution. To eliminate the interference caused by ascorbic acid, such methods as modification of the working electrode with semipermeable membranes and replacement of a mediator have been tested. Those methods have been previously described in the literature as ones that either successfully repelled anions or decreased the oxidation of ascorbic acid. Hypothesis and recommendations for further research are stated.