Bioceramic filled PLA based nanocomposites for biomedical application: An experimental investigation

Abstract

Orthopedic implants require innovative biodegradable materials to eliminate the need for a second surgery post-healing and to counteract the stress shielding issues associated with conventional metallic implants. Polylactic acid (PLA) was chosen for its biocompatibility and biodegradability within the human body. Hydroxyapatite (HAP) and eggshell nanoparticles (ESNPs) were selected as bioceramics due to their similarity to the major constituents of human bone. In the present study, ESNPs were prepared through a ball mill. HAP and Mg particles coated with TiO2 (TiO2@Mg) were synthesized through chemical precipitation and the sol-gel technique, respectively. Subsequently, four samples were prepared: PLA/ESNP/Mg (PEM), PLA/HAP/Mg (PHM), PLA/ESNP/TiO2@Mg (PEMT), and PLA/HAP/TiO2@Mg (PHMT) using the solvent casting process. The addition of Mg demonstrated an enhancement of degradation rates, and TiO2@Mg served to eliminate hydrogen release from Mg. The confirmation of synthesized NPs and PLA nanocomposites was validated through Fourier Transform Infrared Spectroscopy (FTIR), X-ray diffraction (XRD), and Field-Emission Scanning Electron Microscopy (FE-SEM) analysis. The prepared PEMT and PHMT showed tensile strength (42.70 ± 7.55 MPa and 31.57 ± 3.84 MPa), tensile modulus (1624.49 ± 155.05 MPa and 1674.25 ± 87.04 MPa), and shore D hardness (79.41 ± 2.40 SHN and 77.81 ± 3.18 SHN), respectively. The findings showed that PEMT and PHMT composites exhibited enhanced surface roughness, hydrophilicity, degradation rate, and swelling behavior compared to PEM and PHM samples. Moreover, the viability of MG63 cells cultured in different diluted extracts of both samples reached approximately 80 %, indicating no observable cytotoxicity and a hemolysis rate of less than 1.4 %, indicating the potential for use in maxillofacial region implants.