Ultrasensitive electrochemical immunosensor based on Pt nanoparticle-graphene composite

Area of Science:

• Electrochemistry
• Nanomaterials Science
• Biomedical Engineering

Background:

• Human C-reactive protein (CRP) is a key biomarker for inflammation.
• Accurate and sensitive detection of CRP is crucial for early disease diagnosis.
• Existing CRP detection methods can be complex and time-consuming.

Purpose of the Study:

• To develop a novel bioelectrode for the quantitative analysis of human CRP.
• To functionalize platinum nanoparticles (Pt NPs) on graphene for enhanced electrochemical sensing.
• To immobilize anti-CRP antibodies (Ab-CRP) for specific CRP detection.

Main Methods:

• Graphene was synthesized using chemical vapor deposition (CVD) on a glassy carbon electrode.
• Pt NPs were capped with mercaptopropionic acid (MPA) and anchored to graphene.
• Ab-CRP was covalently immobilized on Pt NPs to create the bioelectrode.
• Electrochemical impedance spectroscopy (EIS) was used for characterization and CRP detection.

Main Results:

• The bioelectrode structure was confirmed using scanning electron microscopy (SEM).
• Electrochemical characterization validated the bioelectrode's performance.
• EIS demonstrated a linear response for CRP detection from 10 ng/mL to 10 μg/mL.
• The bioelectrode achieved a sensitivity of 92.86 Ωcm² per decade CRP in pH 7.4 PBS.

Conclusions:

• The developed Pt NP-decorated graphene bioelectrode is effective for sensitive and quantitative CRP detection.
• The optimized bioelectrode shows high sensitivity and selectivity for CRP analysis.
• This biosensor holds potential for clinical applications in inflammatory disease diagnostics.