Composite Membranes of Poly(ε-caprolactone) with Bisphosphonate-Loaded Bioactive Glasses for Potential Bone Tissue Engineering Applications.

Zoi Terzopoulou,Dimitrios Bikiaris,Dimitrios Tzetzis,Diana Baciu,Eleni Gounari,Theodore Steriotis,Georgia Charalambopoulou

doi:10.3390/molecules24173067

Abstract

Poly(ε-caprolactone) (PCL) is a bioresorbable synthetic polyester with numerous biomedical applications. PCL membranes show great potential in guided tissue regeneration because they are biocompatible, occlusive and space maintaining, but lack osteoconductivity. Therefore, two different types of mesoporous bioactive glasses (SiO2-CaO-P2O5 and SiO2-SrO-P2O5) were synthesized and incorporated in PCL thin membranes by spin coating. To enhance the osteogenic effect of resulting membranes, the bioglasses were loaded with the bisphosphonate drug ibandronate prior to their incorporation in the polymeric matrix. The effect of the composition of the bioglasses as well as the presence of absorbed ibandronate on the physicochemical, cell attachment and differentiation properties of the PCL membranes was evaluated. Both fillers led to a decrease of the crystallinity of PCL, along with an increase in its hydrophilicity and a noticeable increase in its bioactivity. Bioactivity was further increased in the presence of a Sr substituted bioglass loaded with ibandronate. The membranes exhibited excellent biocompatibility upon estimation of their cytotoxicity on Wharton’s Jelly Mesenchymal Stromal Cells (WJ-SCs), while they presented higher osteogenic potential in comparison with neat PCL after WJ-SCs induced differentiation towards bone cells, which was enhanced by a possible synergistic effect of Sr and ibandronate.

Highlights

Guided tissue/bone regeneration (GTR/GBR) with barrier membranes is a commonly used approach for enhanced bone regeneration, especially during periodontal defect healing [1]
While non-resorbable membranes show excellent biocompatibility, they do require an additional surgical procedure for their removal and may cause soft tissue dehiscence [6]. These complications resulted in the commercialization of resorbable membranes that are still constructed of bioinert polymers that lack osteoconductive/osteoinductive properties
We demonstrated that the incorporation of 0.5, 1 and 2.5 wt% of nanosized mesoporous BGs in a PCL matrix via the in-situ ring opening polymerization of ε-caprolactone, resulted in a biocompatible PCL composite material with superior mechanical properties, accelerated biodegradation rate and bioactivity [63]

Summary

Introduction

Guided tissue/bone regeneration (GTR/GBR) with barrier membranes is a commonly used approach for enhanced bone regeneration, especially during periodontal defect healing [1] These membranes act as an occlusive barrier that blocks cell migration from connective tissue and epithelium to the defect, which can interfere with tissue regeneration and provides the tissue with adequate time to heal [2,3]. While non-resorbable membranes show excellent biocompatibility, they do require an additional surgical procedure for their removal and may cause soft tissue dehiscence [6]. These complications resulted in the commercialization of resorbable membranes that are still constructed of bioinert polymers that lack osteoconductive/osteoinductive properties. Compared with the most commonly used PLA and PLGA, PCL doesn’t release acidic degradation products that could affect cell growth [4]

Methods

Results

Conclusion