Amperometric Biosensor Based on Glutamate Oxidase to Determine Ast Activity.

This work presents the development of an amperometric biosensor for detecting aspartate aminotransferase (AST) activity in biological fluids using a platinum disk electrode as the working transducer. Optimal concentrations of substrates (aspartate, α-ketoglutarate) and the coenzyme (pyridoxal phosphate) were determined to ensure efficient biosensor operation. A semi-permeable poly-m-phenylenediamine membrane was applied to enhance selectivity against electroactive interferents.

Development and optimisation of the biosensor for aspartate aminotransferase blood level determination.

This work presents the development and optimisation of an amperometric biosensor for determining aspartate aminotransferase (AST) activity in blood serum, using glutamate oxidase and platinum disc electrodes. AST is a key biomarker for diagnosing cardiovascular and liver diseases. The biosensor's bioselective membrane composition and formation protocol and the working solution (aspartate 8 mM, α-ketoglutarate 2 mM, pyridoxal-5-phosphate 100 µM) were optimised.

Adaptation of Conductometric Monoenzyme Biosensor for Rapid Quantitative Analysis of L-arginine in Dietary Supplements.

The present study reports on the development, adaptation, and optimization of a novel monoenzyme conductometric biosensor based on a recombinant arginine deiminase (ADI) for the determination of arginine in dietary supplements with a high accuracy of results. Aiming for the highly sensitive determination of arginine in real samples, we studied the effect of parameters of the working buffer solution (its pH, buffer capacity, ionic strength, temperature, and protein concentration) on the sensitivity of the biosensor to arginine. Thus, it was determined that the optimal buffer is a 5 mM phosphate buffer solution with pH 6.

Electrochemical Biosensors Based on Enzyme Inhibition Effect.

Several electrochemical biosensors based on various enzyme inhibition effects have been designed; their laboratory prototypes have been manufactured and thoroughly investigated. It should be noted that such biosensors are adapted to large-scale production technologies. A number of advantages and disadvantages of developed biosensors based on enzyme inhibition has been discussed.

Application of zeolites and zeolitic imidazolate frameworks in the biosensor development.

Biosensors are advanced devices for analysis of composition of blood, urine, environmental samples, and many other media. Their current development is tightly linked with nanomaterials, such as zeolites and zeolitic imidazolate framework (ZIFs). The present review describes electrochemical (amperometric, conductometric, ISFET) and optical (fluorescent and colorimetric) biosensors that incorporate zeolites and ZIFs in their biorecognition elements.