Computational approach and electrochemical measurements for protein detection with MIP-based sensor

Area of Science:

• Biomedical Engineering
• Materials Science
• Analytical Chemistry

Background:

• Conventional protein detection methods are often slow, costly, and require centralized facilities.
• There is a growing need for rapid, accurate, and accessible protein detection in biomedical settings.

Purpose of the Study:

• To develop and validate an electrochemical sensor for sensitive and selective protein detection.
• To utilize molecular dynamics and experimental procedures for creating a polypyrrol-based molecularly imprinted polymer (MIP) sensor.
• To detect prostate-specific antigen (PSA) as a model protein.

Main Methods:

• Molecular dynamics calculations to predict protein-polymer interactions.
• In situ electropolymerization of polypyrrol (PPy) films to create MIPs.
• Chronoamperometry for optimizing MIP thickness and extraction.
• Square wave voltammetry for PSA detection and quantification.
• Correlation analysis with ELISA for validation in human serum samples.

Main Results:

• Computational analysis confirmed strong binding of PSA to PPy without altering the protein structure.
• The electrochemical sensor demonstrated effective PSA detection in the concentration range of 3x10^-8 to 300 ng/mL.
• An equilibrium dissociation constant (K_d) of (1.02 ± 0.54) × 10^-14 M indicated high binding affinity.
• PSA concentrations measured by the sensor closely correlated with ELISA results in human serum samples.

Conclusions:

• The developed PPy-MIP electrochemical sensor offers a promising platform for fast, low-cost, and highly selective protein detection.
• The sensor exhibits excellent reproducibility and sensitivity for detecting proteins at low concentrations.
• This technology has the potential to significantly advance point-of-care diagnostics and biomedical monitoring.