Amperometric biosensors based on recombinant laccases for phenols determination

Area of Science:

• Biotechnology
• Biosensor Engineering
• Enzyme Technology

Background:

• Biosensors offer sensitive detection of environmental pollutants.
• Recombinant enzymes provide tailored properties for biosensor development.
• Fungal laccases are versatile oxidoreductases applicable in biosensing.

Purpose of the Study:

• To develop and characterize graphite-based biosensors using recombinant fungal laccases.
• To evaluate the performance of these biosensors for the determination of phenolic compounds.
• To compare the efficacy of different recombinant laccases and electrode types.

Main Methods:

• Immobilization of recombinant fungal laccases (rPpL, rMtL) onto graphite electrodes (GE) and printed graphite electrodes (PGE) using BSA and glutaraldehyde.
• Electrochemical characterization of biosensors under steady-state and flow-through regimes.
• Calibration using pyrocatechol as a model substrate and testing response to related compounds.

Main Results:

• GE-based biosensors exhibited hyperbolic calibration graphs with EC(50) of 0.7 mM and sensitivity of 3.8 mA/M for pyrocatechol, increasing to 4 A/M with higher rPpL loading.
• PGE-based biosensors in a flow-through cell showed varying EC(50) (0.6–4.0 mM) and sensitivity (0.11–1.9 mA/M) with rPpL.
• Biosensors demonstrated stability over 6–9 days and responded to various phenolic compounds and their derivatives.

Conclusions:

• Recombinant fungal laccases are suitable for biosensor engineering.
• Developed biosensors effectively determine phenols and related compounds in different operational regimes.
• The study highlights the potential of these biosensors for environmental monitoring and analysis.