Polymer-Functionalized Upconversion Nanoparticles for Light/Imaging-Guided Drug Delivery

Area of Science:

• Nanotechnology
• Materials Science
• Biomedical Engineering

Background:

• Upconversion luminescence nanoparticles (UCNPs) exhibit strong upconversion luminescence (UCL), enabling near-infrared (NIR) to UV/visible light conversion for potential biomedical applications.
• Existing light-responsive drug delivery systems face limitations due to UV light's tissue damage and poor penetration, issues UCNPs can potentially overcome.
• Synthesized UCNPs are typically hydrophobic, necessitating surface functionalization for plasma stability and improved drug delivery capabilities.

Purpose of the Study:

• To review recent advancements in UCNP synthesis with diverse shapes and sizes.
• To discuss the role and strategies of polymer coating for UCNP-based drug delivery systems.
• To explore multifunctional UCNP-based nanoparticles for enhanced therapeutic and diagnostic applications.

Main Methods:

• Overview of recent UCNP synthesis techniques.
• Discussion of polymer coating strategies for UCNPs.
• Review of UCNP-polymer composites for drug delivery, photothermal therapy, and MRI.

Main Results:

• Polymers provide colloidal stability, prevent protein corona formation, act as drug matrices, and enable stimuli-responsive drug release.
• Various polymers have been successfully used to coat UCNPs, with a focus on light-responsive polymers for controlled drug delivery.
• Multifunctional nanoparticles integrating UCNPs with materials like carbon-based NPs and nanoMOFs enhance drug loading, photothermal therapy, and MRI capabilities.

Conclusions:

• Polymer-coated UCNPs show promise for advanced drug delivery systems, offering improved stability and functionality.
• Further research into drug loading, release kinetics, and toxicity of these polymer-coated UCNPs is crucial for clinical translation.
• UCNPs, when functionalized with polymers and integrated into multifunctional platforms, represent a significant advancement in theranostics.