A sandwich HIV p24 amperometric immunosensor based on a direct gold electroplating-modified electrode

Area of Science:

• Biomedical Engineering
• Immunotechnology
• Diagnostic Assays

Background:

• Acquired immune deficiency syndrome (AIDS) is a critical global health issue, necessitating accurate and early diagnosis of human immunodeficiency virus (HIV) infection.
• Laboratory diagnosis of HIV is vital for controlling AIDS transmission and management.
• The HIV-1 p24 antigen is an early biomarker for HIV infection, detectable before host antibodies develop.

Purpose of the Study:

• To develop a novel, highly sensitive sandwich HIV p24 immunosensor for early HIV detection.
• To enhance electrode properties using direct gold nanoparticle electroplating for improved electrochemical performance.
• To evaluate the immunosensor's performance against established diagnostic methods like ELISA.

Main Methods:

• Fabrication of a gold nanoparticle-modified electrode via chronoamperometry for enhanced conductivity and reversibility.
• Development of a sandwich immunosensor assay utilizing the modified electrode to capture the HIV p24 antigen.
• Optimization of electrochemical detection parameters to establish a linear relationship between signal and p24 concentration.

Main Results:

• The developed immunosensor demonstrated a linear response to p24 antigen concentration from 0.01 ng/mL to 100 ng/mL (R > 0.99).
• Achieved a low detection limit of 0.008 ng/mL for the p24 antigen.
• Exhibited sensitivity over two orders of magnitude higher than traditional ELISA methods for p24 detection.

Conclusions:

• The gold nanoparticle-based HIV p24 immunosensor offers a sensitive, rapid, and reproducible method for early HIV diagnosis.
• The biosensor's ease of use, mild conditions, and anti-interference capabilities make it suitable for clinical applications.
• This technology holds significant potential for improving HIV/AIDS diagnostics and public health outcomes.