Biosensors for phenol derivatives using biochemical signal amplification

Area of Science:

• Electrochemistry
• Biosensors
• Enzyme kinetics

Background:

• Tyrosinase (PPO) is crucial for biosensor development.
• Enhancing biosensor sensitivity is vital for accurate phenol detection.
• Cooperative enzyme functioning offers a promising strategy for biosensor improvement.

Purpose of the Study:

• To compare two enzyme cooperative approaches for enhancing tyrosinase (PPO) biosensor sensitivity.
• To evaluate monoenzyme (PPO) and bienzyme (PPO-GDH, PPO-HRP) electrodes for amperometric phenol detection.
• To demonstrate the quantitative assay capabilities of developed biosensors for various phenolic compounds.

Main Methods:

• Construction of monoenzyme (PPO) and bienzyme (PPO-GDH, PPO-HRP) electrodes using agar-agar gel immobilization.
• Amperometric detection of l-tyrosine at -50 mV versus saturated calomel electrode (SCE).
• Quantitative determination of various phenols using the developed biosensor systems.

Main Results:

• The PPO-GDH bienzyme electrode exhibited the highest sensitivity (74 mA M⁻¹).
• The PPO-HRP bienzyme system showed a 32-fold increase in sensitivity compared to the monoenzyme PPO electrode (0.01 mA M⁻¹).
• All constructed biosensors successfully demonstrated the quantitative assay of diverse phenolic compounds.

Conclusions:

• Bienzyme electrode configurations significantly enhance tyrosinase biosensor sensitivity for phenol detection.
• The PPO-GDH combination offers superior performance for amperometric phenol sensing.
• The developed biosensors are effective tools for the quantitative analysis of various phenolic compounds.