Impact of enzyme stabilizers on the characteristics of biomodules for bioluminescent biosensors

• The biomodule of an enzyme-based bioluminescent biosensor has been developed.
• Activity and stability of biomodule was increased by adding of enzymes’ stabilizers.
• The biomodule containing 100 μM of DTT was sensitive to model toxic substances.
• The biomodule produced from starch gel was more sensitivity to toxic substances.
• The developed biological module can be used for a toxicity assay.

The biomodule of bioluminescent biosensor based on a coupled enzyme system NADH:FMN-oxidoreductase and luciferase, co-immobilized with substrates in dried starch or gelatin gels, has been developed. We studied the impact of several stabilizers—dithiothreitol (DTT), bovine serum albumin (BSA) and mercaptoethanol (ME) on the biomodule's activity, storage stability and sensitivity to toxic substances. The inclusion of stabilizers increases the activity of the biological module by more than 150%. To achieve the combination of high activity, prolonged storage time and acute sensitivity to toxic substances within maximum permissible concentration we used starch gel as a carrier adding 100 μM DTT to the immobilized preparation. The gelatin-based biological module had greater storage stability than the starch-based one but demonstrated less sensitivity to toxic substances.