Polymerization induced self-assembly (PISA) is a facile <i>in situ</i> method for producing block copolymer nanoparticles (PNPs). It produces PNP solutions with high solids content, requires no post-synthetic purification steps, and easily accesses cylinder and vesicle morphologies. Using a PISA approach, we investigate the aqueous polymerization of poly(glycerol monomethacrylate)-<i>block</i>-poly(2-hydroxypropyl methacrylate) (PGMA-PHPMA) in the presence of phenylacetic acid, a hydrophobic drug. PGMA is the corona-block, while PHPMA is the core-block. The resulting PNP nanostructure was characterized by transmission electron microscopy and dynamic light scattering, while drug encapsulation was quantified using nuclear magnetic resonance diffusion ordered spectroscopy. For a constant PHPMA degree of polymerization, an increase in the targeted drug loading expands the PNP size and shifts the morphology from spherical micelles to cylindrical micelles to vesicles. At a targeted drug concentration of 32 mg/mL – twice the water solubility limit of phenylacetic acid – the encapsulation efficiency reaches a maximum. An increase in the PHPMA degree of polymerization, however, has minimal impact on encapsulation efficiency. Our findings are compared to predictions from thermodynamic models.

Encapsulation of a hydrophobic drug in block copolymer nanoparticles during polymerization induced self-assembly

Fall 2022 abstracts, posters, and presentations will launch in mid-September.

ACS Fall 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.