Last decades the interest of nano- and biotechnology's application in the diagnostics and the monitoring of compounds increased rapidly [1,2]. Electrochemical enzymatic biosensors are the most popular and widely used in clinical analysis, pharmaceuticals, food processing industries and environmental monitoring due to their specificity and sensitivity in complex systems [2]. Diabetes mellitus — the most common endocrine disorder of carbohydrate metabolism and is considered a chronic disease caused by improper regulation of glucose in the blood [2,3]. Usually high sensitivity and selectivity, the rapidity and the reversibility, the application and the excellent catalytic activities are characterized for electrochemical biosensors immobilized by enzyme and polymers [2,4,5].
The main aim of this research was to synthesize polymeric nanocompositions (PNC) with embedded glucose oxidase and to develop glucose biosensors immobilized by such PNC with following addition of enzyme. To achieve electron transfer between the solution and graphite rod electrode soluble mediator – phenazine methosulfate (PMS) was used. It was predicted that formed by enzyme-assisted polymerization polyaniline and polypyrrole nanocomposites are able to facilitate indirect electron transfer and has the positive effect on the sensitivity and selectivity of developed system [2,4,5]. The most suitable immobilization method by PNC and the kind of polymer were chosen in order to improve analytical characteristics of glucose biosensor during research. Cyclic voltammetry was used to investigate the reversibility of electrochemical reaction and the suitability of developed glucose biosensor. Meanwhile, another electrochemical method such as chronoamperometry was used for the investigations of analytical characteristics and the stability of the developed system. It was evaluated, that the addition of PMS is necessary, because in the absence of mediator no electron transfer is able. Although the presence of polypyrrole nancomposites on the surface of working electrode enhanced the glucose analytical signal the most, however the lower limit of detection was obtained in the presence of polyaniline nanocompositions. Enzyme-assisted PNC could be apply in the construction of electrochemical glucose biosensors and could be use in different diagnostic applications.
