Biocompatibility and chemical reaction kinetics of injectable, settable polyurethane/allograft bone biocomposites

Page, JM; Prieto, EM; Dumas, JE; Zienkiewicz, KJ; Wenke, JC; Brown-Baer, P; Guelcher, SA

HERO ID

4404349

Reference Type

Journal Article

Year

2012

Language

English

PMID

22871639

HERO ID 4404349
In Press No
Year 2012
Title Biocompatibility and chemical reaction kinetics of injectable, settable polyurethane/allograft bone biocomposites
Authors Page, JM; Prieto, EM; Dumas, JE; Zienkiewicz, KJ; Wenke, JC; Brown-Baer, P; Guelcher, SA
Journal Acta Biomaterialia
Volume 8
Issue 12
Page Numbers 4405-4416
Abstract Injectable and settable bone grafts offer significant advantages over pre-formed implants due to their ability to be administered using minimally invasive techniques and to conform to the shape of the defect. However, injectable biomaterials present biocompatibility challenges due to the potential toxicity and ultimate fate of reactive components that are not incorporated in the final cured product. In this study the effects of stoichiometry and triethylenediamine (TEDA) catalyst concentration on the reactivity, injectability, and biocompatibility of two component lysine-derived polyurethane (PUR) biocomposites were investigated. Rate constants were measured for the reactions of water (a blowing agent resulting in the generation of pores), polyester triol, dipropylene glycol (DPG), and allograft bone particles with the isocyanate-terminated prepolymer using an in situ attenuated total reflection Fourier transform infrared spectroscopy technique. Based on the measured rate constants, a kinetic model predicting the conversion of each component with time was developed. Despite the fact that TEDA is a well-known urethane gelling catalyst, it was found to preferentially catalyze the blowing reaction with water relative to the gelling reactions by a ratio >17:1. Thus the kinetic model predicted that the prepolymer and water proceeded to full conversion, while the conversions of polyester triol and DPG were <70% after 24h, which was consistent with leaching experiments showing that only non-cytotoxic polyester triol and DPG were released from the reactive PUR at early time points. The PUR biocomposite supported cellular infiltration and remodeling in femoral condyle defects in rabbits at 8weeks, and there was no evidence of an adverse inflammatory response induced by unreacted components from the biocomposite or degradation products from the cured polymer. Taken together, these data underscore the utility of the kinetic model in predicting the biocompatibility of reactive biomaterials.
Doi 10.1016/j.actbio.2012.07.037
Pmid 22871639
Wosid WOS:000312765000026
Is Certified Translation No
Dupe Override No
Is Public Yes
Language Text English
Keyword Index Medicus
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