The electrospun poly(ε‐caprolactone)/fluoridated hydroxyapatite nanocomposite for bone tissue engineering

Abstract

Biodegradable cell-incorporated scaffolds can guide the regeneration process of bone defects such as physiological resorption, tooth loss, and trauma which medically, socially, and economically hurt patients. Here, 0, 5, 10, and 15 wt% fluoridated hydroxyapatite (FHA) nanoparticles containing 25 wt% F − and 75 wt% OH − were incorporated into poly (ε-caprolactone) (PCL) matrix to produce PCL/FHA nanocomposite scaffolds using electrospinning method. Then, scanning electron microscopy (SEM), X-ray diffraction (XRD) pattern, and Fourier transform infrared spectroscopy (FTIR) were used to evaluate the morphology, phase structure, and functional groups of prepared electrospun scaffolds, respectively. Furthermore, the tensile strength and elastic modulus of electrospun scaffolds were investigated using the tensile test. Moreover, the biodegradation behavior of electrospun PCL/FHA scaffolds was studied by the evaluation of weight loss of mats and the alternation of pH in phosphate buffer saline (PBS) up to 30 days of incubation.Then, the biocompatibility of prepared mats was investigated by culturing MG-63 osteoblast cell line and performing MTT assay. In addition, the adhesion of osteoblast cells on prepared electrospun scaffolds was studied using their SEM images. Results revealed that the fiber diameter of prepared electrospun PCL/FHA scaffolds alters between 700 and 900 nm. The mechanical assay illustrated the mat with 10 wt% FHA nanoparticles revealed the highest tensile strength and elastic modulus. The weight loss alternation of mats determined around 1% to 8% after 30 days of incubation. The biocompatibility and cell adhesion of mats improved by increasing the amounts of FHA nanoparticles. K E Y W O R D S biocompatibility, electrospinning, nano-fluoridated hydroxyapatite, poly(ɛ-caprolactone), tensile strength 1 | INTRODUCTION Fibrous structure scaffolds exhibits the similar size to the extracellular matrix structure, protein absorption, and cell attachment in tissue engineering applications. 1 As an effective and low-cost fabricating method, electrospinning has been applied to produce continuous fibers from the nanoscale to the microscale. 2 Tissue engineering scaffolds should essentially possess several properties such as desirable biocompatibility, simple fabrication, controllable degradation rate, and sufficient mechanical properties. Accordingly, diverse synthetic polymers have been electrospun and modified as well as natural polymersto perform in different tissues. 3 Among these, poly(ε-caprolactone) (PCL) as a synthetic and biodegradable polymer possesses the biocompatibility and rheological and viscoelastic properties, prepared as a fibrous structure via the electrospinning. 4-6 Hence, PCL fibers can be selected as an appropriate candidate for tissue engineering scaffolds, regenerating skin, cartilage, bone, and cardiac constructs. 7 PCL is a polyester with a semicrystalline structure and amorphous domains,

Implementing Taguchi method to analyze electrospinning parameters influence on Mg‐doped fluorapatite nanoparticles‐poly (ε‐caprolactone) nanocomposite scaffold (Mg‐FA NPs/PCL) properties

“…In addition, it is possible to load higher concentration of well-dispersed bio-ceramic nanoparticle sin the polymer fibers and consequently enhancing biological properties. 8,10,27 F I G U R E 7 SEM images of the optimized Mg-FA NPs/PCL fibrous nanocomposite containing 1 wt% NPs after (A) 28 days soaking in the SBF,…”

“…According to the fact that decreasing diameter of fibers and eliminating agglomerated nanoparticles and beads cause to improve the scaffold properties, the electrospinning process was developed in an economical, facile, and operational method, titled Taguchi optimization approach. Based on the results of the literatures and our previous studies, 8,10 we chose five parameters to discover the mechanism of sol-gel method in line with the previous work. 16 All solvents were analytically graded and were used as received without any further purification.…”

“…The structure of bone extracellular matrix (ECM) includes a fibrous collagen with homogeneously dispersed hydroxyapatite (HA) nanocrystals, therefore, applying electrospun scaffolds for bone tissue engineering has interestingly been increased. A numerous polymers have been employed to engineer the ECM tissues including either as natural polymers such as collagen, gelatin, chitosanor as synthetic polymers for example poly (lactic acid) (PLA), poly (lactide‐co‐glycolide) (PLGA), poly (glycolic acid) (PGA), polyurethane (PU), poly (ethylene glycol) diacrylate (PEGDA), and poly ( ε ‐caprolactone) (PCL) 1‐3,5‐9 . Owing to the appropriate mechanical properties and controllable degradation rate of synthetic polymers, researchers are extensively interested in applying them for bone tissue engineering, which can be used either in pure form or combined with natural polymers or bioceramic materials to increase the biocompatibility and osteoconductivity and make them more similar to the bone tissue 2,6,10‐12 …”

Hydroxyapatite‐Incorporated Composite Gels Improve Mechanical Properties and Bioactivity of Bone Scaffolds

“…In the past, different forms of tissue scaffolds were fabricated using HA, such as electrospun fibers, 3D printed thermoplastic polymers, and freeze‐dried matrices. [ 31–34 ] In our work, we have generated HA‐reinforced, hydrogel‐based scaffolds which have high water content and have biomimetic properties. The reinforcement of the hydrogel‐based scaffolds with HA renders them physically stable and the resulting constructs are easily handled.…”

“…[ 37–39 ] In our study, commercially available nonprocessed HA microparticles were used at different concentrations within a gelatin‐based hydrogel (GelMA) matrix to increase the mechanical stability of the resulting scaffolds and promote osteogenic differentiation of the preosteoblasts. [ 32–35 ] Our approach is a unique way to achieve highly tunable osteoinductive scaffolds and enables to control the osteogenic differentiation of predifferentiated stem cells.…”