mPEG-PLGA used as part of nanogel intraocular drug delivery system

PolySciTech (www.polyscitech.com) provides a wide array of biodegradable block copolymers including mPEG-PLGA. Recently these types of polymers were used as a precursor for a 2,2-bis(2-oxazoline) crosslinked nanogel designed for ocular delivery of bevacizumab. Read more: Hu, Chao-Chien, Jen-Ray Chaw, Yu-Chih Chen, Chin-Fu Chen, and Hsia-Wei Liu. "A Novel Thermo-Responsive Nanogel for Intraocular Drug Delivery." Journal of Computational and Theoretical Nanoscience 12, no. 5 (2015): 762-768. http://www.ingentaconnect.com/content/asp/jctn/2015/00000012/00000005/art00012

“Abstract: The novel amphiphilic hydrophilic–hydrophobic block copolymers of methoxy-poly(ethylene glycol)-block-poly(lactic-co-glycolic acid) (mPEG-PLGA) were synthesized by the ring-opening polymerization, cross-linked with 2,2-bis(2-oxazoline) (BOX) and the chemical structures were characterized by 1H nuclear magnetic resonance (1H-NMR). Cross-linked mPEG-PLGA-BOX block copolymers formed a core–shell micellar structure with a critical micelle concentration of 9.21 × 10–4 mg/mL. The mPEG-PLGA-BOX micelles were spherical with a hydrodynamic diameter of between 26.10 nm to 39.70 nm. A solution containing mPEG-PLGA-BOX micelles exhibited a fast and reversible sol–gel phase transition behavior that could convert into nanogels at body temperature. The pharmacokinetic release rate of anti-vascular endothelial growth factor (VEGF) entrapped in nanogels were examined in vitro. Release profiles of the anti-VEGF agents (bevacizumab) showed that there was sustained release for approximately 30 days. Released bevacizumab inhibited the RF6A cells growth, which showed drug delivery system may provide localized and sustained release of bevacizumab over an extended period. The mPEG-PLGA-BOX nanogel has been successfully synthesized and determined as thermosensitive and biocompatible. This suggests that the nanogel may be considered as a novel biomaterial with potential as the form of injectable dilute dispersions or as in situ gelling carrier for extended anti-VEGF drug release to treat intraocular neovascular diseases.”