Magnetic Nanoparticles Stabilized by Phosphorylcholine-Containing Polymer for Label-Free C-Reactive Protein Detection

Area of Science:

• Biomaterials Science
• Nanotechnology
• Analytical Chemistry

Background:

• C-reactive protein (CRP) is a key biomarker for inflammation and cardiovascular disease risk.
• Existing CRP detection methods can be complex, time-consuming, or require antibodies.
• There is a need for simple, rapid, and cost-effective CRP assays.

Purpose of the Study:

• To develop a novel, antibody-free assay for C-reactive protein (CRP) detection.
• To utilize magnetic nanoparticles (MNPs) functionalized with a phosphorylcholine-containing polymer for CRP sensing.
• To establish both visual and colorimetric detection methods for CRP.

Main Methods:

• Synthesis and characterization of poly[(methacrylic acid)-ran-(methacryloyloxyethyl phosphorylcholine)]-functionalized magnetic nanoparticles (PMAMPC-MNPs).
• Utilizing PMAMPC-MNPs aggregation for visual CRP detection in the presence of Ca²⁺.
• Employing the peroxidase-like activity of MNPs for colorimetric CRP quantification via TMB substrate.

Main Results:

• PMAMPC-MNPs were successfully synthesized and characterized using various techniques (ATR-FTIR, TEM, DLS, TGA, XRD).
• Visual detection of CRP was achieved through nanoparticle aggregation.
• An antibody-free colorimetric assay demonstrated a linear detection range of 1-5 μg/mL with a limit of detection (LOD) of 1.0 μg/mL.
• Successful CRP detection was achieved in diluted rabbit serum at a clinically relevant concentration (3 μg/mL).

Conclusions:

• The developed PMAMPC-MNP assay provides a simple and effective platform for CRP detection.
• The assay is antibody-free, reducing complexity and potential cost.
• This method holds promise for sensitive and rapid CRP quantification, aiding in cardiovascular disease risk assessment.