Functional magnetic nanoparticles for protein delivery applications: understanding protein-nanoparticle interactions

Area of Science:

• Biomaterials Science
• Nanotechnology
• Drug Delivery Systems

Background:

• Iron oxide nanoparticles (IONPs) functionalized with thermo-responsive polymers can encapsulate and release therapeutic proteins triggered by heat.
• Achieving clinical relevance requires a delivery system with a lower critical solution temperature (LCST) above human body temperature.

Purpose of the Study:

• To develop and characterize IONPs coated with poly-N-isopropylmethacrylamide (PNIPMAM) for temperature-controlled protein delivery.
• To optimize PNIPMAM chain length and IONP size for an LCST of approximately 45 °C.

Main Methods:

• Synthesis and characterization of 16 nm IONPs coated with 19 kDa PNIPMAM.
• Encapsulation efficiency and release kinetics of various proteins.
• Assessment of release in the presence of competitor proteins and serum.
• Comparison of magnetic heating versus conventional heating for protein release.

Main Results:

• Optimized PNIPMAM-coated IONPs achieved an LCST of ca. 45 °C.
• Successful encapsulation and release of diverse proteins, influenced by molecular weight and glycosylation.
• Minimal protein leakage below LCST, with efficient release above LCST.
• Magnetic heating accelerated protein release compared to conventional methods, maintaining bulk solution temperature.

Conclusions:

• PNIPMAM-coated IONPs provide a viable platform for controlled therapeutic protein delivery.
• The system demonstrates tunable release kinetics based on protein properties and heating method.
• This approach holds promise for targeted and efficient protein-based therapies.