Biobased Hyperbranched Poly(ester)s of Precise Structure for the Release of Therapeutics

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Bob A. Howell Tracy Zhang Patrick B. Smith


Hyperbrached poly(ester)s derived from naturally-occurring biomonomers may serve as excellent platforms for the sustained-release of therapeutics. Those generated from glycerol are particularly attractive. Traditionally, the difference in reactivity of the hydroxyl groups of glycerol has precluded the formation of well-defined polymers at high monomer conversion without gelation. Using the Martin-Smith model to select appropriate monomer ratios (ratios of functional groups), polymerization may be carried out to high conversion while avoiding gelation and with the assurance of a single type of endgroup. Various agents may be attached via esterification, amide formation or other process. Sustained release of the active agent may be readily achieved by enzyme-catalyzed hydrolysis.

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HOWELL, Bob A.; ZHANG, Tracy; SMITH, Patrick B.. Biobased Hyperbranched Poly(ester)s of Precise Structure for the Release of Therapeutics. Medical Research Archives, [S.l.], v. 9, n. 1, jan. 2021. ISSN 2375-1924. Available at: <>. Date accessed: 05 mar. 2021. doi:
Research Articles


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