Abstract
In the present work, the role of content, size and chemical composition of gel-derived bioactive glass particles from the SiO2–CaO–P2O5 system in modulating the in vitro bioactivity, osteoinductive properties and long-term (up to 15 months) degradation behaviour of poly(ε-caprolactone)-based composite films was investigated. Bioactivity was assessed in simulated body fluid (SBF) and HEPES-free Dulbecco’s modified Eagle medium (DMEM) supplemented with 10% foetal bovine serum (FBS), while hydrolytic degradation tests were performed in phosphate buffer saline. Obtained composite films showed excellent calcium phosphate (CaP) layer forming ability in both SBF and DMEM-10% FBS. However, kinetics of bioactivity process strongly depended on the type of medium used. The layer of amino acids and proteins, derived from cell culture medium, on the surfaces of composites created barrier that inhibited release of the ions on the one hand, while increasing nucleation density of calcium phosphates, affecting the morphology of formed CaP layers on the other. The presence of bioactive glass fillers was shown to impart osteoinductive properties to obtained films, supporting osteoblast attachment and proliferation, as well as stimulating cell differentiation and also matrix mineralization process in vitro. We showed that kinetics of bioactivity process and also osteoinductive properties of composite films could be easily modulated with the use of different contents and chemical compositions of fillers. The results showed that modification of PCL matrix with bioactive glass particles accelerated its degradation. We proved that the degradation rate of composites could be controlled and optimized for bone regeneration, in particular by using bioactive fillers causing different calcium phosphate layer forming ability on the surfaces of composites, depending on particle size and chemical composition. We have presented new opportunities to design and obtain multifunctional composites with tunable degradation and bioactivity kinetics, as well as biological properties that can meet complex requirements of bone tissue engineering.
Highlights
Biomaterials for bone tissue engineering (BTE) applications should degrade progressively at a rate matching the regeneration of new bone in vivo to allow full restoration of native tissue structure and functions [1, 2]
A2-PCL and S2-PCL composite films containing 12 and 21 vol% glass particles of \ 45 lm size and pure PCL material were examined in terms of in vitro bioactivity by soaking them in simulated body fluid (SBF) and cell culture medium (DMEM supplemented with 10% foetal bovine serum (FBS)) for 1, 3, 7 and 14 days
Layer morphologies varied between materials incubated in SBF and Dulbecco’s modified Eagle medium (DMEM)-10% FBS—spherical forms developed in cell culture medium were significantly smaller compared to that formed in SBF
Summary
Biomaterials for bone tissue engineering (BTE) applications should degrade progressively at a rate matching the regeneration of new bone in vivo to allow full restoration of native tissue structure and functions [1, 2]. The degradation behaviour of the materials should vary based on target applications, namely material form (e.g. scaffold, barrier membrane) and implantation site. The gradual resorption of three-dimensional porous scaffolds, used for filling bone defects, allows to create space for the new bone tissue growth, while the necessary structural support is provided until full regeneration of the tissue [2]. The controlled degradation rate of the membrane allows to maintain its mechanical integrity and spacemaintaining properties over the entire period of bone regeneration on the one hand and to exclude the need for its surgical removal on the other [3, 4].
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
