Novel poly(hydroxyalkanoates)-based composites containing Bioglass® and calcium sulfate for bone tissue engineering

Abstract

Three different poly(hydroxyalkanoates) (PHAs), copolymers of poly(3-hydroxybutyrate) (P3HB), have been used to make composites using two different fillers, bioactive glass (type 45S5 Bioglass®) and calcium sulfate dihydrate. The PHAs used were poly(3-hydroxybutyrate-co-3-hydroxyvalerate) [PHBHV] and two copolymers of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) [PHBHHx]. The aim of the study was the fabrication and characterization of the new composites and the assessment of the influence of the particular filler combination on the physical properties and bioactivity of the films. The thermal behaviour was studied using differential scanning calorimetry while mechanical properties were evaluated using dynamic mechanic thermal analysis and tensile strength test. The mechanical and thermal properties were affected by particles addition. The distribution of the particles in the polymer matrix, observed by scanning electron microscopy, was directly related to the mechanical properties. The surface characteristics were investigated by contact angle measurements and Raman spectroscopy. The extent of formation of hydroxyapatite (HA) upon immersion in simulated body fluid (SBF) depended on the polymer used, the amount of fillers employed and the time of immersion in SBF. Bioactivity was enhanced in the composites with a rise of hydrophilicity. The HA formation was controllable with time in the case of PHBHHx composites.

Additive manufacturing of poly[(R)-3-hydroxybutyrate-co-(R)-3-hydroxyhexanoate] scaffolds for engineered bone development

“…In vivo studies showed that PHB and PHBV composite scaffolds reinforced with hydroxyapatite particles can integrate well with the host tissue to promote bone growth (Doyle et al ., ; Chen and Wu, ; Jack et al ., ). However, despite the promising results achieved, the brittleness of PHB and PHBV can limit their application as in vivo load‐bearing tissue substitutes (Ye et al ., ; Garcia‐Garcia et al ., ). As a member of the PHAs family, poly[( R )‐3‐hydroxybutyrate‐co‐( R )‐3‐hydroxyhexanoate) (PHBHHx) (Figure ) is a promising biomaterial, showing better ductility and processing properties in comparison with PHB and PHBV (Doi et al ., ; Chen et al ., ; Zhao et al ., ).…”

“…In addition, PHBHHx‐based composites containing an osteoconductive or piezoelectric inorganic filler (e.g. bioactive glasses or BaTiO 3 particles) have been investigated for bone‐regeneration approaches (Jing et al ., ; Garcia‐Garcia et al ., ; Ke et al ., ; Wu et al ., ).…”

Bionic Design, Materials and Performance of Bone Tissue Scaffolds

“…However, certain disadvantages have limited their clinical applications. If special methods are used to combine these two materials, at a certain ratio, into a composite material, it is possible to optimize their biological performance [ 36 , 37 ]. Yanen Wang and Kikuchi [ 38 ] etc., have successfully synthesized a hydroxyapatite/collagen composite ( Figure 3 ), which can be successfully involved in bone reconstruction, as it can be replaced by new bone.…”

Additive Manufacturing of Poly(3-hydroxybutyrate-co-3-hydroxyhexanoate)/poly(ε-caprolactone) Blend Scaffolds for Tissue Engineering

“…Due to the relatively long alkyl side chain, poly[(R)-3-hydroxybutyrate- co -(R)-3-hydroxyhexanoate) (PHBHHx) exhibits lower crystallinity, a broader processing window and higher elasticity compared with PHB and PHBV [ 8 ]. Among the different investigated biomedical applications, PHBHHx has been proposed as scaffolding material for bone regeneration thanks to its piezoelectric behavior and cytocompatibility when cultured with osteoblasts and bone marrow cells [ 9 , 10 , 11 , 12 , 13 , 14 ]. In addition, recent articles showed that PHBHHx in the form of microgrooved membrane [ 15 ], aligned nanofibers [ 16 ] or carbon nanotubes-loaded composite materials [ 17 ] well supports the osteogenesis of human mesenchymal stem cells.…”