Sensing HIV Protease and Its Inhibitor Using "Helical Epitope"-Imprinted Polymers

Area of Science:

• Biomolecular Engineering
• Analytical Chemistry
• Virology

Background:

• HIV protease (PR) is a critical target for antiretroviral therapy.
• Developing selective and sensitive detection methods for HIV PR and its inhibitors is essential.
• Molecularly imprinted polymers (MIPs) offer a promising platform for molecular recognition.

Purpose of the Study:

• To fabricate helical epitope-mediated molecularly imprinted polymers (HEMIPs) on a quartz crystal microbalance (QCM) chip for HIV PR detection.
• To evaluate the affinity, selectivity, and detection limit of the developed HEMIPs sensor.
• To establish a sandwich assay for screening HIV PR inhibitors.

Main Methods:

• Selected a helical epitope-peptide from HIV PR as a template for HEMIPs fabrication.
• Synthesized HEMIPs on a QCM chip using peptide template, water, TFE, and ACN.
• Removed template molecules and characterized the HEMIPs chip's binding properties.
• Developed a sandwich assay using the HEMIPs chip to detect nelfinavir, an HIV PR inhibitor.

Main Results:

• The HEMIPs chip demonstrated high affinity for HIV PR_85-94 peptide, His-tagged HIV PR, and HIV PR (K_d values in picomolar range).
• The sensor achieved a detection limit of 0.1 ng/mL for HIV PR_85-94.
• The developed chip successfully bound HIV PR and subsequently nelfinavir, enabling a sandwich assay.

Conclusions:

• HEMIPs on QCM chips are effective for high-affinity and selective detection of HIV PR.
• The developed sensor platform can be utilized for screening HIV PR inhibitors, potentially improving HIV therapy.
• This technique shows promise for broader applications in virus assays.