Laboratory prototype of electrochemical biosensor for the quantitative analysis of alanine aminotransferase activity

Aim. To develop an electrochemical biosensor for the quantitative assessment of alanine aminotransferase (ALT) activity. Materials and Methods. Three-electrode amperometric scheme of detection with platinum disk working electrode covered with bioselective element based on pyruvate oxidase and photopolymer. Measurements were carried out with an applied potential of 0.6 V. Results. A laboratory prototype of an amperometric biosensor for ALT detection was developed. The immobilization method was selected, and the procedure was optimized for the type of bioselective material used. The composition of the working buffer was optimized, namely, the kind of buffer, buffer capacity, pH, content of coenzymes of the bioselective material (phosphate ions, magnesium ions, thiamine pyrophosphate), and the analyte (alanine, ketoglutarate, pyridoxal phosphate). The reproducibility of immobilization and reproducibility of responses of the developed biosensor, as well as its analytical characteristics (linear range, detection limit, response time, etc.), were analyzed. Conclusions. The developed biosensor was characterized by sufficiently good analytical parameters for its further optimization and testing when working with real blood serum samples.