Miniaturized DyP Peroxidase-Based Biosensor for On-Site Open Air Use

Area of Science:

• Electrochemistry
• Biosensors
• Enzyme catalysis

Background:

• Hydrogen peroxide (H2O2) is a key biomarker in various biological processes.
• Developing sensitive and user-friendly biosensors for H2O2 detection is crucial for diagnostics.

Purpose of the Study:

• To develop a miniaturized, disposable, and user-friendly electrochemical biosensor for H2O2 detection.
• To optimize the biosensor by immobilizing wild type and variant dye-decolorizing peroxidases (DyPs) on nanostructure-modified electrodes.

Main Methods:

• Immobilization of DyPs on self-assembled monolayer (SAM)-coated and nanostructure-modified screen-printed electrodes (SPEs).
• Utilizing gold and silver nanoparticles (AuNPs and AgNPs) on carbon-based (C-SPE) and gold-based (Au-SPE) electrodes.
• Characterization using resonance Raman spectroscopy and electrochemical performance evaluation.

Main Results:

• The wild type DyP/SAM/AuNP/C-SPE construct demonstrated superior performance.
• Achieved a linear response range of 30–475 μM for H2O2.
• Reported a sensitivity of 234 ± 9 mA·M⁻¹·cm⁻² and a limit of detection (LOD) of 3.5 μM under open air conditions.

Conclusions:

• The developed DyP-based electrochemical biosensor is suitable for single-use, on-site H2O2 measurements in samples like physiological fluids.
• The biosensor platform offers potential for customization for detecting other hydroperoxides and enhancing specific traits through DyP manipulation.