mPEG-PLGA used for modulating drug release from microparticles

PolySciTech (www.polyscitech.com) provides a wide array of block copolymers including mPEG-PLGA diblock polymers. Recently the impact of mPEG-PLGA block copolymer molecular weight on drug release relative to drug molecule molecular weight was investigated. Read more: Feng, Shuibin, Lei Nie, Peng Zou, and Jinping Suo. "Effects of drug and polymer molecular weight on drug release from PLGA‐mPEG microspheres." Journal of Applied Polymer Science 132, no. 6 (2015). http://onlinelibrary.wiley.com/doi/10.1002/app.41431/full

“ABSTRACT: This study investigated the effects of drug and polymer molecular weight on release kinetics from poly (g-co-glycolic acid)-methoxypoly(ethyleneglycol) (PLGA-mPEG) microspheres. Bovine serum albumin (BSA, 66 kDa), lysozyme (LZ, 13.4 kDa), and vancomycin (VM, 1.45 kDa) were employed as the model drugs, and encapsulated in PLGA-mPEG microspheres of different molecular weight. Release of macromolecular BSA was mainly dependent on diffusion of drug at/ near the surface of the matrix initially and dependent on degradation of matrix at later stages, while, the small drug of vancomycin seemed to depend totally on diffusion for the duration of the release study. The release behavior of lysozyme was similar to bovine serum albumin, except a shorter lag period. PLGA-mPEG molecular weight also affected the release behavior of bovine serum albumin and lysozyme, but not obviously. PLGA-mPEG microspheres in smaller molecular weight seemed to degrade more quickly to obtain a mass lose and matrix erosion, and thus, an accelerated release rate of bovine serum albumin and lysozyme. Vancomycin released much faster than bovine serum albumin and lysozyme, and exhibited no lag period, as it is thought to be diffusion-controlled. Besides, vancomycin showed no difference in release behavior as PLGA-mPEG molecular weight change. Keywords: biodegradable;biomaterials;drug delivery systems”