Optimization of the Process Parameters of Antibacterial Bioactive Glass/Polycaprolactone Composite Scaffold Printed by 3D Method

Abstract

In this study, a 3D bioactive glass composite scaffold containing 2 mol% silver/polycaprolactone (PCL) was synthesized by a 3D printer with the advantages of reproducibility and high flexibility in shape and size. The effective parameters (printer parameters, ratio of glass-phase, polymer phase, and solvent in printer ink) were determined for printing of nanocomposite scaffold by Taguchi method. Characterization of printed scaffolds was performed using X-ray diffraction, scanning electron microscope, infrared spectroscopy, bioactivity test, atomic emission spectroscopy, toxicity test, and cell proliferation. The results related to the synthesis of silver-containing bioglass by sol-gel method and heat treated at 550°C offered nanoparticles with an average diameter of less than 15 nm and a homogeneous distribution of silver in the matrix. Ratio of polymer phase to glass powder equivalent to 0.5, concentration of polymer in solvent of 50%, retraction of 1.5, and drive gear of 1200 are obtained as the optimum conditions for scaffold printing with acceptable quality (percentage, size and distribution of holes, regular structure of layers, and repeatability). The fabricated scaffold in optimal conditions revealed significant antibacterial properties, good bioactivity, acceptable cell viability, and high ALP activity. 3D printed BG/PCL nanocomposite scaffolds with macro (up to 500 µm) and micro size of holes and porosity percentage up to 64% in the structure can be a promising candidate for bone tissue engineering.