Evaluating the Effect of 3D Printed Polycaprolactone-Boric Acid Scaffold on Proliferation and Bone Differentiation of Human Bone Marrow Mesenchymal Stem Cells

Biocompatible implants are a suitable option in the reconstruction and repair of damaged bone and can be considered instead of bone grafting. However, the materials used to produce such substitutes may not have sufficient bioactivity in the body. Boric acid (BA) is a weak acid of boron with water solubility, semi-conductivity, and anti-inflammatory properties. It also stimulates bone formation in the body. The aim of this study was to produce a bone substitute composed of polycaprolactone (PCL) and BA using a 3D-printer and analyse its effect on the proliferation and bone differentiation of human bone marrow mesenchymal stem cells (hBMSCs). PCL scaffolds containing different concentrations of BA were produced using a 3D printer and were characterized with scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, and inductively coupled plasma mass spectrometry (ICP-MS). In addition, the proliferation and bone differentiation of human bone marrow mesenchymal stem cells (hBMSCs) on the PCL-BA scaffolds were evaluated using MTT assay, alizarin red staining, and alkaline phosphatase (ALP) measurement. BA was gradually released from the 3D scaffolds and PCL-BA scaffolds have a suitable three-dimensional structure for cell attachment and proliferation. According to the MTT results, PCL-BA scaffolds did not cause any toxicity to hBMSCs. Although PCL-BA scaffolds had significant osteoinduction potential, scaffold containing lower concentrations of BA had a better effect on osteogenesis. BA incorporation enhanced the bioactivity of PCL scaffolds; however, the BA concentration was a determining factor in the direction of bone differentiation of hBMSCs.