Abstract
In this study, the effects of material thickness and processing method on the degradation rate and the changes in the mechanical properties of poly(lactic-co-glycolic acid) material during simulated physiological degradation were investigated. Two types of poly(lactic-co-glycolic acid) materials were considered: 0.12 mm solvent-cast films and 1 mm compression-moulded plates. The experimental results presented in this study were compared to the experimental results of Shirazi et al. (Acta Biomaterialia 10(11):4695–703, 2014) for 0.25 mm solvent-cast films. These experimental observations were used to validate the computational modelling predictions of Shirazi et al. (J Mech Behav Biomed Mater 54: 48–59, 2016) on critical diffusion length scale and also to refine the model parameters. The specific material processing methods considered here did not have a significant effect on the degradation rate and the changes in mechanical properties during degradation; however, they influenced the initial molecular weight and they determined the stiffness and hardness of the poly(lactic-co-glycolic acid) material. The experimental observations strongly supported the computational modelling predictions that showed no significant difference in the degradation rate and the changes in the elastic modulus of poly(lactic-co-glycolic acid) films for thicknesses larger than 100 μm.
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Acknowledgments
Funding support was provided by the Structured PhD Programme in Biomedical Engineering and Regenerative Medicine (BMERM), funded under the Programme for Research in Third-Level Institutions (PRTLI) Cycle 5 and co-funded under the European Regional Development Fund (ERDF). The authors would like to thank Dr. Benjamin Chalmers (School of Chemistry, NUI Galway) for helping with GPC measurements and Dr. Eadaoin Timmins (NCBES, NUI Galway) for helping with AFM measurements. The authors would also like to thank Proxy Biomedical Ltd (Co. Galway, Ireland) for sample preparation.
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Yury Rochev and Peter McHugh are joint senior authors
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Shirazi, R.N., Aldabbagh, F., Ronan, W. et al. Effects of material thickness and processing method on poly(lactic-co-glycolic acid) degradation and mechanical performance. J Mater Sci: Mater Med 27, 154 (2016). https://doi.org/10.1007/s10856-016-5760-z
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DOI: https://doi.org/10.1007/s10856-016-5760-z