Surface coating affects behavior of metallic nanoparticles in a biological environment

Area of Science:

• Nanotechnology
• Materials Science
• Biomedical Engineering

Background:

• Silver nanoparticles (AgNPs) and superparamagnetic iron oxide nanoparticles (SPIONs) show medical potential.
• Their physicochemical characteristics and behavior in biological environments require thorough understanding.
• Varying sizes and surface coatings influence nanoparticle properties and biocompatibility.

Purpose of the Study:

• To evaluate the impact of surface coatings on the colloidal stability of AgNPs and SPIONs.
• To assess nanoparticle behavior in simulated and real biological environments.
• To understand how different media compositions affect nanoparticle stability and transformation.

Main Methods:

• Dynamic light scattering (DLS) and electrophoretic light scattering (ELS) were used.
• Transmission electron microscopy (TEM) visualized nanoparticle behavior.
• Nanoparticles were dispersed in ultrapure water (UW), protein-free cell culture medium (BM), and protein-supplemented medium (BMP).

Main Results:

• Different surface coatings resulted in varying nanoparticle stabilities across different media.
• Negative surface charge and strong adsorption of coating agents enhanced stability in electrolyte-rich fluids.
• Proteins in biological fluids provided colloidal stabilization to nanoparticles, irrespective of their composition or surface charge.
• Nanoparticle behavior in rat whole blood and plasma highlighted the critical role of biological medium composition.

Conclusions:

• Surface coating is a key factor in determining nanoparticle colloidal stability in biological media.
• Proteins play a vital role in stabilizing nanoparticles within biological fluids.
• Comprehensive physicochemical characterization is essential for evaluating metallic nanoparticles in diverse biological systems.