Peptide cleavage-based electrochemical biosensor coupling graphene oxide and silver nanoparticles

Area of Science:

• Electrochemistry
• Biotechnology
• Nanomaterials

Background:

• Prostate specific antigen (PSA) is a key biomarker for prostate cancer diagnosis.
• Sensitive and selective detection of PSA is crucial for early disease detection.
• Existing PSA detection methods have limitations in sensitivity, selectivity, or cost.

Purpose of the Study:

• To develop a novel electrochemical biosensor for sensitive and selective detection of PSA.
• To utilize a peptide cleavage mechanism combined with graphene oxide (GO) and silver nanoparticles (AgNPs) for signal amplification.
• To establish a reliable method for PSA quantification in biological samples.

Main Methods:

• Fabrication of a gold electrode modified with a specific peptide as the recognition element.
• Utilizing graphene oxide (GO) for immobilization and silver ion reduction to form silver nanoparticles (AgNPs) in the absence of PSA.
• Monitoring the electrochemical response, specifically silver stripping peaks, which are modulated by PSA-induced peptide cleavage.
• Investigating the effect of PSA concentration on the electrochemical signal.

Main Results:

• The biosensor demonstrated a remarkable decrease in electrochemical response upon PSA detection due to PSA-induced peptide cleavage.
• The developed method showed high sensitivity and selectivity for PSA analysis.
• The combination of peptide cleavage, GO, and AgNPs effectively amplified the electrochemical signal.
• A clear correlation was observed between PSA concentration and the reduction in electrochemical signal.

Conclusions:

• The novel electrochemical biosensor based on peptide cleavage and GO/AgNPs nanocomposites provides a promising platform for sensitive and selective PSA detection.
• This approach offers a new strategy for developing advanced electrochemical biosensors for disease biomarker analysis.
• The findings highlight the potential of integrating molecular recognition events with nanomaterial-based signal amplification for clinical diagnostics.