Abstract
The availability of osteogenic proteins for orthopedic applications has led to great interest in developing delivery systems for these substances. Standard release rate models are applicable in most biological settings, but orthopedic implants usually bear mechanical loads. To determine whether a release rate model for load bearing applications must consider mechanical stress, the effects of dynamic mechanical stress on the in vitro release kinetics of two model proteins, bovine albumin (BA) and trypsin inhibitor (TI), from a biodegradable film were evaluated. Biodegradable poly(lacticco-glycolic acid) cylindrical implants with embedded proteins were subjected to cyclic three point bending loading of 720 cycles/day at 0.4 Hz for 2 weeks. Protein release into solution, swelling and mass loss changes, molecular weight degradation, and the presence of microstructural stress cracks and pores in the polymer carrier were evaluated. Cumulative BA and TI releases with time were significantly higher when a cyclic bending load was applied and increased with the magnitude of the load. Mass loss was not significantly greater, nor was swelling or molecular weight change of the polymer carrier in this 2-week interval. Pores on the surface of...Continue Reading
References
Nov 1, 1978·The Journal of Pharmacy and Pharmacology·D L WiseJ F Howes
May 1, 1978·The Journal of Bone and Joint Surgery. British Volume·B McKibbin
Dec 1, 1992·Journal of Biomedical Materials Research·Y MatsusueY Ikada
Dec 1, 1992·Journal of Biomedical Materials Research·E R EdelmanR Langer
Jul 1, 1992·Journal of Orthopaedic Research : Official Publication of the Orthopaedic Research Society·J M GuiseA F Tencer
Sep 1, 1991·Biomaterials·E R EdelmanM Klagsbrun
Jan 1, 1991·Journal of Biomedical Materials Research·P TörmäläP Rokkanen
Jan 1, 1990·International Orthopaedics·O BöstmanP Rokkanen
Sep 28, 1990·Science·R Langer
Jun 1, 1989·Journal of Biomedical Materials Research·A F TencerK L Brown
Oct 1, 1989·Proceedings of the National Academy of Sciences of the United States of America·J KostR Langer
Jan 1, 1982·Annals of Surgery·C C Chu
Sep 1, 1984·Biomaterials·A G Thombre, K J Himmelstein
Oct 1, 1983·In Vitro·J B MurrayM Klagsburn
Oct 1, 1994·Journal of Biomedical Materials Research·S C LeeW C Hayes
Aug 1, 1993·Journal of Biomedical Materials Research·T VerrecchiaP Couvreur
Apr 1, 1990·Journal of Applied Biomaterials : an Official Journal of the Society for Biomaterials·A U DanielsK P Andriano
Apr 1, 1991·Journal of Applied Biomaterials : an Official Journal of the Society for Biomaterials·F R RozemaA J Pennings
Citations
Jul 11, 2007·Journal of Materials Science. Materials in Medicine·Manuela C C M SobralM H Gil
Jul 19, 2005·Journal of Orthopaedic Research : Official Publication of the Orthopaedic Research Society·Hans GollwitzerAxel Stemberger
Jun 10, 2017·Regenerative Biomaterials·Ying LiYubo Fan
Jul 29, 2020·Frontiers in Psychology·Martin Mabunda BalukuKathleen Otto
Nov 20, 2016·Advanced Drug Delivery Reviews·Julia WangMark W Grinstaff