Magnetic polyphosphazene@Au particles as substrates for multiple-detection of immunoproteins by surface-enhanced...

Area of Science:

• Materials Science
• Nanotechnology
• Analytical Chemistry

Background:

• Developing sensitive and efficient substrates for Surface-Enhanced Raman Spectroscopy (SERS) is crucial for advanced analytical applications.
• Magnetic nanoparticles offer advantages in sample enrichment and separation, simplifying complex matrix analysis.
• Polyphosphazene-based composites are emerging materials with tunable properties for various applications.

Purpose of the Study:

• To fabricate gold-coated magnetic polyphosphazene (MPCTP@Au) composite particles with enhanced SERS activity.
• To investigate the magnetic responsiveness and SERS performance of the synthesized MPCTP@Au particles.
• To develop a SERS immunoassay system for the sensitive and simultaneous detection of immunoproteins.

Main Methods:

• Fabrication of magnetic polyphosphazene (MPCTP) particles via precipitation polycondensation.
• Deposition of gold nanoparticles onto MPCTP to form MPCTP@Au composite particles.
• Characterization of SERS activity using DTNB as a model Raman reporter and development of a SERS immunoassay for immunoglobulin G (IgG) detection.

Main Results:

• MPCTP@Au composite particles demonstrated sensitive SERS activity with a limit of detection (LOD) of 10^-8 mol/L for DTNB.
• The magnetic core enabled efficient analyte enrichment and separation, simplifying sample pretreatment.
• The SERS immunoassay achieved highly sensitive quantitative determination of human IgG, rabbit IgG, and their mixtures, with LODs as low as 10 fg/mL.

Conclusions:

• MPCTP@Au composite particles are effective SERS-active substrates with excellent magnetic properties.
• The developed SERS immunoassay system provides a highly efficient platform for sensitive immunoprotein analysis.
• These findings highlight the broad application prospects of MPCTP@Au particles in high-performance analytical applications.