A-BioHPG: A Hydrophilic Biodegradable and Hemocompatible Hyperbranched/Dendritic Polyketal Polyglycerol with Tunable Degradation

We report the design and synthesis of a biodegradable hyperbranched polyether polyketal polyol, containing acid-labile ketal groups with controlled degradation, high water solubility, excellent hemocompatibility, and cell compatibility. For this, we have developed a new AB₂-type acid-labile monomer, 2-((4-(2-(oxiran-2-ylmethoxy) ethoxy)tetrahydro-2H-pyran-4-yl)oxy)ethan-1-ol (OTPE). The OTPE monomer is copolymerized with glycidol through anionic ring-opening multibranching polymerization generating OTPE-incorporated hyperbranched polyglycerol (A-BioHPG) with varying degradable monomer content. Gel permeation chromatography assisted degradation studies indicated polymer stability at physiological pH, while controlled degradation is observed under acidic pH, and the data support the homogeneous distribution of the OTPE monomer throughout the polymer. The hemocompatibility of A-BioHPG is assessed by blood coagulation, platelet activation, red blood cell lysis and aggregation, and cell compatibility with endothelial cells. Our findings show that A-BioHPG is a promising candidate for use in multitude of biomedical applications, including but not limited to solubility enhancement, drug delivery, tissue engineering, and bioconjugation.