Tuesday, July 19, 2016

PLGA-diol precursors from PolySciTech used in biodegradable polyurethane development at University of Washington

PolySciTech Division of Akina, Inc. (www.polyscitech.com) provides a wide variety of research polymers. This includes PLGA di-alcohol precursors such as HO-PLGA-TEG-PLGA-OH (Polyvivo AK076) and butanediol initiated HO-PLGA-OH (PolyVivo AP112). The dialcohol units on these polymers can react with isocyanate groups to form urethane linkages. Since the polymer is di-functionalized, it joins into the forming chain of a polyurethane and acts as a chain extender linked di-isocyanates together. Although typical polyurethanes are not biodegradable, the incorporation of PLGA into the polyurethane backbone in this way renders the polymer as a degradable matrix useful for a wide array of applications. Recently, researchers at University of Washington utilized PLGA-diols from PolySciTech to generate novel polyurethanes. Read more about this exciting technology here: Blakney, Anna K., Felix Simonovsky, Ian T. Suydam, Buddy D. Ratner, and Kim A. Woodrow. "Rapidly Biodegrading PLGA-Polyurethane Fibers for Sustained Release of Physicochemically Diverse Drugs". ACS Biomaterials Science & Engineering 2016 (http://pubs.acs.org/doi/abs/10.1021/acsbiomaterials.6b00346)


“Abstract: Sustained release of physicochemically diverse drugs from electrospun fibers remains a challenge and precludes the use of fibers in many medical applications. Here we synthesize a new class of polyurethanes with PLGA moieties that degrade faster than polyurethanes based on polycaprolactone. The new polymers, with varying hard to soft segment ratios and fluorobenzene pendant group content, were electrospun into nanofibers and loaded with four topically relevant but physicochemically diverse small molecule drugs. Polymers were characterized using GPC, XPS and 19F NMR. The size and morphology of electrospun fibers were visualized using SEM, and drug/polymer compatibility and drug crystallinity were evaluated using DSC. We measured the in vitro release of physicochemically diverse drugs, and polymer degradation and cytotoxicity of biodegradation products were evaluated in cell culture. We show that these newly synthesized PLGA-based polyurethanes degrade up to 65-80% within four weeks, and are cytocompatible in vitro. The resulting drug-loaded electrospun fibers were amorphous solid dispersions. We found that increasing the hard to soft segment ratio of the polymer enhances the sustained release of positively charged drugs, while increasing the fluorobenzene pendant content caused more rapid release of some drugs. Increasing the hard segment or fluorobenzene pendant content of segmented polyurethanes containing PLGA moieties allows for modulation of physicochemically diverse drug release from electrospun fibers, while maintaining a biologically relevant biodegradation rate.”

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