A specific identification platform based on biscuit-like bismuth nanosheets for label-free electrochemical...

Area of Science:

• Electrochemistry
• Biosensing
• Nanomaterials Science

Background:

• Label-free electrochemical immunosensors offer sensitive detection methods.
• Human immunoglobulin G (hIgG) is a key biomarker in various diseases.
• Developing robust platforms for hIgG detection is crucial for clinical diagnostics.

Purpose of the Study:

• To construct a label-free electrochemical immunosensor for detecting human immunoglobulin G (hIgG).
• To utilize biscuit-like bismuth nanosheets (BiNSs) and a composite of multi-wall carbon nanotubes-chitosan-gold nanoparticles (MWCNTs-Chit-AuNPs) as the sensing platform.
• To evaluate the analytical performance and potential clinical applicability of the developed immunosensor.

Main Methods:

• Fabrication of a composite nanomaterial using BiNSs, MWCNTs, chitosan, and AuNPs on a glassy carbon electrode (GCE).
• Immobilization of anti-hIgG antibodies onto the AuNPs for specific antigen capture.
• Electrochemical detection of hIgG using cyclic voltammetry and electrochemical impedance spectroscopy.

Main Results:

• The BiNSs provided a large electroactive surface area, enhancing antibody loading.
• The MWCNTs-Chit-AuNPs composite facilitated efficient electron transfer and stable antibody immobilization.
• The immunosensor achieved a wide linear range (0.01-1000 ng/mL) and a low detection limit (4.26 pg/mL) for hIgG.
• The sensor demonstrated excellent reproducibility, specificity, stability, and performance in human serum samples.

Conclusions:

• The developed electrochemical immunosensor based on BiNSs and MWCNTs-Chit-AuNPs offers a sensitive and reliable method for hIgG detection.
• The unique properties of the nanomaterials contribute to enhanced sensing performance.
• This immunosensor holds significant potential for practical applications in clinical diagnosis.