Synthesis of polymerizable cyclodextrin derivatives for use in adhesion-promoting monomer formulations
Rafael L. Bowen, Gary E. Schumacher, Clifton M. Carey, Anthony A. Giuseppetti, Kathleen M. Flynn, Charles M. Guttman
Objectives. Based on extensive literature research and molecular modelingresults, the hypothesis was that Beta-Cyclo Dextrin (BCD), containing 21 hydroxyl groups per molecule, could be derivatized to form a "family" of Polymerizable Cyclodestrin Derivatives (PCDs) comprising water-soluble monomers having several polymerizable (cross-linking) and ionizable ligand (binding) groups per molecule, each attached by hydrolytically stable ether (-C-O-C-) linkages. Due to hydrophilic ligands and residual hydroxyl groups, these PCDs should penetrate hydrated layers of dentin and enamel to interact with collagen and tooth mineral. The styrene-like polymerizable groups can readily homopolymerize and also copolymerize with (meth)acrylates. The long-term objective is to enable attachment of PCD-containing monmeric formulations to hydrated hydrophilic substrates, including biological tissues, and polymerization forming durably bound cross-linked polymers. Methods: Recrystallized and dried BCD with a stabilizer was heated at ~60 oC for 4 d in an aqueous solution of Ca(OH)2 plus KOH (pH ~ 13) with 6 mol of vinylbenzyl chloride (to attach polymerizable groups) plus 15 mol of 6-bromohexanoate (to attach hydrophilic carboxylate ligands) per mol of BCD. Results: Analyses indicated that PCD reaction products contained more than 30 different combinations (plus permutations) of vinylbenzyl and hexanoate groups, iwth up to 7 combined on most molecules. Significance: Although the hypothesis was supported, improved synthetic methods are underway to obtain more vinylbenzyl groups and hexanoate groups on every PCD molecule. Cabilities for obtaining durable bonding of hydrolytically stable resins to hydrous biological tissues and other substrates with similar but optimized formulations being developed in this ongoing project will provide widespread benefits.
, Schumacher, G.
, Carey, C.
, Giuseppetti, A.
, Flynn, K.
and Guttman, C.
Synthesis of polymerizable cyclodextrin derivatives for use in adhesion-promoting monomer formulations, Journal of Research (NIST JRES), National Institute of Standards and Technology, Gaithersburg, MD, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=853606
(Accessed December 10, 2023)