Practical application of electrochemical enzyme biosensors

Abstract

The electrochemical biosensor is an integrated receptor-transducer device, which can convert a biological response into a measurable electrical signal. Because of its important features like selectivity, sensitivity, stability, reproducibility, linearity, and low cost, biosensors have a wide range of applications. The aim of this paper is to review our achievements in the development of electrochemical enzyme biosensors and the possibility of their applications in food industry, agriculture and environmental control. The specific structural features of transducers in the developed amperometric, potenciometric and conductometric enzyme biosensors are discussed. The laboratory prototypes were fabricated and systematically tested for the determination of glycoalkaloids, mycotoxins, heavy metal ions and pesticides in the agriculture and environment samples as well as some components of food and dietary supplements. They demonstrated fast, highly selective, sensitive and correct analitycal operation and also the possibility to modulate main characteristics to comply with the specific requirements for the practical purposes. It is important that the manufacture of such miniaturized electrochemical biosensors may be adapted to the technologies of large-scale production.

Solutions for enhancement of sensitivity and metrological reliability of conductometric biosensor systems

“…In general, the unstable sensitivity of conductometric systems with two-electrode sensors can be accounted for the complex electrochemical processes in a conductometric cell and complicated equivalent circuit of this type of transducers [14,[16][17][18][19]. Briefly, the current across the transducer is defined by the sum of impedances of its three regions: two near-electrode regions and the impedance between them, which includes the active resistance of solution in the interelectrode region and the reactive resistance of the interelectrode capacitance, connected to it in parallel.…”

“…Voltage of the imbalance signal is received from the diagonal of the bridge by means of operational amplifiers. The informative signal (its component is in phase with the generator signal) is selected by a synchronous detector of the selective nanovoltmeter [14,15].…”