A new polyaniline-catalase-glutaraldehyde-modified biosensor for hydrogen peroxide detection

Area of Science:

• Electrochemistry
• Biosensor Technology
• Analytical Chemistry

Background:

• Hydrogen peroxide (H2O2) is a contaminant in milk that requires sensitive detection methods.
• Enzyme-immobilized biosensors offer a promising approach for selective analyte determination.

Purpose of the Study:

• To develop and characterize a novel biosensor for hydrogen peroxide (H2O2) determination in milk.
• To optimize the biosensor performance for accurate and sensitive H2O2 quantification.

Main Methods:

• Electrochemical construction of a polyaniline (PANI) film modified with glutaraldehyde.
• Immobilization of catalase enzyme onto the PANI film.
• Electrochemical impedance spectroscopy for monitoring assembly and immobilization.
• Amperometric measurements at -0.3 V vs. Ag/AgCl for H2O2 detection.

Main Results:

• The biosensor demonstrated a linear response to H2O2 concentrations ranging from 5.0 × 10-6 to 1.0 × 10-4 M.
• A low detection limit of 2.18 × 10-6 M for H2O2 was achieved.
• Optimization studies identified key parameters influencing biosensor performance, including pH, temperature, and enzyme loading.

Conclusions:

• The developed catalase/PANI/glutaraldehyde biosensor is a viable tool for sensitive H2O2 detection in milk.
• The electrochemical approach provides an efficient platform for biosensor fabrication and analysis.
• Further optimization can enhance the biosensor's applicability in food safety analysis.