Macromolecules, Vol.52, No.10, 3775-3786, 2019
Therapeutic Methacrylic Comonomers for Covalently Controlled Release from Mechanically Robust Bone Cement: Kinetics and Structure-Function Relationships
To transform biologically inert poly(methyl methacrylate) (PMMA) bone cement into a tunable drug eluting biomaterial, we have employed polymerizable therapeutic methacrylic (TMA) comonomers that use the methacrylic carbonyl bond as a platform for hydrolytically controlled drug release. Changing the identity of the tether bond allows us to select release patterns ranging from rapid release (up to 6.5 times more efficient than drug-eluting cements based on passive diffusion) to long-term anchorage. Further, TMA cements retain their mechanical strength throughout drug release, outperforming both PMMA and diffusion-based cements in compressive strength after aging. We also found that certain factors exert secondary effects on the patterns of covalently controlled release from TMA cements, including TMA/methyl methacrylate (MMA) copolymer architecture (created by different reactivity ratios between each TMA/MMA pairing) and cement hydrophilicity. TMA comonomers represent a valuable tool for tuning the bioactivity and cure behavior of bone cement to meet a range of demands in the operating room.