Submicron polyacrolein particles in situ embedded with upconversion nanoparticles for bioassay

Area of Science:

• Materials Science
• Nanotechnology
• Biomedical Engineering

Background:

• Upconversion nanoparticles (UCNPs) offer unique photoluminescence properties for bioimaging.
• Surface modification is crucial for UCNP integration into biological systems.
• Existing methods may face challenges in stability and biocompatibility.

Purpose of the Study:

• To develop a new surface modification technique for Yb(3+)/Er(3+)-codoped NaYF4 UCNPs.
• To create stable, water-dispersible polymer-UCNP composites for bioassays and imaging.
• To demonstrate the utility of these UCNP-polymer particles in in vivo imaging.

Main Methods:

• Two-stage precipitation polymerization of acrolein around UCNPs under alkaline conditions.
• Utilized tetramethylammonium hydroxide as both initiator and hydrophilizing agent.
• Characterized UCNP-polymer particles for size, dispersibility, photoluminescence, and stability.

Main Results:

• Achieved up to 90% polyacrolein yield, indicating efficient encapsulation.
• Synthesized UCNP-polymer particles with controlled diameters (mean 260 nm) and excellent aqueous dispersibility.
• Demonstrated stable photoluminescence and chemical stability of the modified UCNPs.
• Successfully applied the particles for in vivo optical whole-animal imaging.

Conclusions:

• The developed acrolein polymerization method provides facile and lossless embedment of UCNPs.
• The resulting polymer-UCNP particles possess desirable properties for bioassay applications.
• The UCNP-polymer composites are suitable for in vivo optical imaging, showcasing their biomedical potential.