Synthesis and Characterization of PEG-b-PLGA Copolymer-Based Nano Formulations via Flash Nano Precipitation

Abstract

Flash Nanoprecipitation (FNP) is a popular and straightforward technique that involves the assembly of amphiphilic copolymers into nanoparticles for biomedical applications. The method is economical and fast for the versatile structure of block copolymers and their ability to form nanoparticles. Medical grade nanoparticles offer unique opportunities, such as controlled drug release, imaging contrast agents, and hyperthermic cancer treatment. The objective of the study was to produce two types of nanoparticles via the FNP process, polyethylene glycol–poly lactic-co-glycolic acid (PEG-PLGA) nanoparticles with different molecular weights and PEG-PLGA coated iron oxide nanoparticles (IONPs). The ring-opening polymerization (ROP) technique was used to successfully synthesize amphiphilic block-copolymers with hydrophilic PEG, and hydrophobic PLGA part. A standardized procedure was introduced to produce polymers with varying molecular weights. This involved using stannous octoate as a catalyst to get a 50:50 ratio of lactide to glycolide. The ratio of a PLGA copolymer promotes enhanced breakdown compared to a PLGA copolymer containing a higher quantity of either of the two monomers. Following that, the development of targeted medicine delivery methods was conceptualized through the introduction of IONPs. The IONPs were synthesized by the utilization of a thermal decomposition process, using iron oleate as a precursor. This method resulted in the production of particles dispersed in tetrahydrofuran (THF) with a consistent size of 10-20nm, possessing magnetic characteristics. Bare polymeric nanoparticles (PNPs) with sizes 80-160nm were formed by introducing amphiphilic block copolymer PEG-PLGA with different weight percentages in a solvent to a multi-inlet-vortex mixture (MIVM) without the use of a stabilizer. Another set of experiments was conducted in which IONPs were incorporated into the polymers to produce nanocarriers that were slightly bigger, but their particle stability over time increased. The effective attachment of IONPS within the polymer shell was verified using transmission electron microscopy (TEM). These nanocarriers should have the inherent potential of individual units to exhibit biodegradability, biocompatibility, and a good toxicological profile as further research is required for applicational prospects. Consequently, these engineered particles can serve as ideal carriers for diverse drug delivery applications, with polymers providing temporal control and iron oxide ensuring the treatment target specific.