Amperometric immunobiosensor for α-fetoprotein using Au nanoparticles/chitosan/TiO(2)-graphene composite based...

Area of Science:

• * Electrochemistry
• * Nanomaterials Science
• * Biosensor Technology

Background:

• * Development of sensitive and selective biosensors is crucial for early disease diagnosis.
• * Label-free detection methods reduce assay complexity and cost.
• * Nanomaterials offer unique properties for enhancing biosensor performance.

Purpose of the Study:

• * To develop a simple, label-free amperometric immunosensor for protein detection.
• * To utilize a composite film of TiO(2)-graphene, chitosan, and gold nanoparticles.
• * To immobilize antibodies for the detection of alpha-fetoprotein (AFP).

Main Methods:

• * Fabrication of a modified glassy carbon electrode (GCE) with TiO(2)-graphene, chitosan, and gold nanoparticles (AuNPs).
• * Immobilization of α-fetoprotein antibody onto the AuNPs for AFP capture.
• * Electrochemical detection using differential pulse voltammetry (DPV) to measure changes in electron transfer.

Main Results:

• * Achieved a wide detection range for AFP from 0.1 to 300 ng mL(-1).
• * Obtained a low limit of detection of 0.03 ng mL(-1) at S/N=3.
• * Demonstrated high sensitivity, selectivity, stability, and generality of the developed sensing strategy.

Conclusions:

• * The developed immunosensor provides a sensitive and reliable platform for protein detection.
• * The strategy shows potential for broader applications in detecting other biomolecules.
• * This label-free approach offers advantages for clinical diagnostics and biocompound analysis.