mPEG-PLA for protein delivery

PolySciTech (www.polyscitech.com) provides a wide variety of PEG-b-PLA polymers (Polyvivo AK**) in our online catalog. Recently these kinds of polymer have been used along with lysine to generate biocompatible micelle formulation capable of carrying recombinant human erythropoietin showing the potential of this material to deliver protein based drugs with maintained bioactivity. Shi, Yanan, Fengying Sun, Dan Wang, Renyu Zhang, Changlin Dou, Wanhui Liu, Kaoxiang Sun, and Youxin Li. "Enhancement of bioavailability by formulating rhEPO ionic complex with lysine into PEG–PLA micelle." Journal of nanoparticle research 15, no. 10 (2013): 1-10. http://link.springer.com/article/10.1007/s11051-013-2002-x

“Abstract: A composite micelle of ionic complex encapsulated into poly(ethylene glycol)-poly(d,l-lactide) (PEG–PLA) di-block copolymeric micelles was used for protein drug delivery to improve its pharmacokinetic performance. In this study, recombinant human erythropoietin (rhEPO, as a model protein) was formulated with lysine into composite micelles at a diameter of 71.5 nm with narrow polydispersity indices (PDIs < 0.3). Only a trace amount of protein was in aggregate form. The zeta potential of the spherical micelles was ranging from −0.54 to 1.39 mv, and encapsulation efficiency is high (80 %). The stability of rhEPO was improved significantly in composite micelles in vitro. Pharmacokinetic studies in rats showed significant, enhanced plasma retention of the composite micelles in comparison with native rhEPO. Areas under curve (AUCs) of the rhEPO released from the composite micelles were 4.5- and 2.3-folds higher than those of the native rhEPO and rhEPO-loaded PEG–PLA micelle, respectively. In addition, the composite micelles exhibited good biocompatibility using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) assay with human embryonic kidney (HEK293T) cells. All these features are preferable for utilizing the composite micelles as a novel protein delivery system.”