Biocompatibility Evaluation of Electrospun Scaffolds of Poly (L-Lactide) with Pure and Grafted Hydroxyapatite

Abstract

<p>The objective of this work was to evaluate the biocompatibility of scaffolds of poly(<em>L</em>-lactide) with pure and grafted hydroxyapatite, at various concentrations of reinforcement. The biocompatibility tests were carried out <em>in vivo </em>in Wistar rats by implanting the material into the subcutaneous and muscle tissues from 1 to 14 weeks and evaluating the surrounding tissue stained with hematoxylin-eosin. For <em>in vitro </em>assays, MTT and neutral red assay were used to evaluate any cytotoxicity in Mioblast Muscle C2C12 Cells (ATCC® CRL-1772™) and Bovine Coronary Artery Endothelial Cells (BCAEC); <em>Escherichia coli </em>and <em>Staphylococcus aureus </em>were used to evaluate bacterial adhesion. All variants of scaffolds provoked a mild inflammatory response, without showing necrosis. No evidence of cytotoxicity was presented in cell viability tests and good bacterial cell adhesion was visualized for all of the materials studied.</p>

Electrospun Nanofibers for Tissue Engineering: Desired Properties

“…The value of the electrospinning technique has been reported over the last 10 years [1 -13]. This technique leads to the production of versatile nanofibers that possess a diverse set of properties [3] and can be used in several applications such as tissue engineering [1,2,4,12], drug delivery systems [4,5,7,8,10,11], and biotechnology [6,13], amongst others.…”

“…Among the interesting properties of electrospun nanofibers, the high tensile strength, flexibility, reduced permeability of water [14], high surface area [15], biocompatibility [2], and biodegradability [16], are a few mentioned.…”

“…The above properties can always be designed through the choice of a specific polymer [4] that is used as a matrix and can be functionalized with a great variety of biomaterials such as metals [9,12], ceramics [1,2] or other polymers [6,13], these above biomaterials can be used to functionalize the nanofibers with extra properties. Such is the case of the integration of an antimicrobial effect on the nanofibers thanks to some bioactive properties, for example, silver nanoparticles [12] and curcumin [13], or conductive properties by adding graphene [17], polyaniline [18] or having therapeutics effect loading pharmaceutical drugs in/on the surface of the nanofibers such as dexamethasone [10], sildenafil citrate [11], just to mention some examples.…”

“…1). These structures can be prepared with biomaterials that resemble the chemical composition of tissues, using natural biomaterials, for example, hydroxyapatite [1,2] which promotes the regeneration of bone tissue. By the same time, the nanofibers are reabsorbed and become part of the tissue [19].…”

Temperature effect on the porosity of hydroxyapatite scaffolds and its use in tissue engineering

“…The use of hydroxyapatite as porous scaffolds or as a bioactive coating material in medical devices is justified because ceramics resist oxidation and corrosion in the physiological environment and possess great resistance to friction and wear; however, hydroxyapatite by itself has poor biomechanical properties, its ability to withstand flexion and compression stresses is very low, causing it to fracture easily. Given these drawbacks, in recent decades several organic compounds of the extracellular matrix such as fibronectin, vitrionectin, osteopontin, growth factors and type I collagen, among others, have been added to hydroxyapatite coatings in order to improve osteoconduction, cell adhesion and the mechanical properties of the coating [4][5][6][7][8][9]. A relatively new promising material that can improve the mechanical properties of the coating is graphene [10], since it has great flexibility and mechanical rigidity, in addition to its properties as an electrical conductor that could help coating methods based on voltage, such as electrodeposition and electrophoresis [11,12].…”