Stimulation of Bone ingrowth using YSZ/ β-TCP/PCL composite bilayer coating on 316 LSS scaffold for orthopedic application

Abstract

The demand towards ideal tissue construct using polymer and ceramics made the researchers to do the search of polymer composites with desirable properties. Material selection for the composite play a major role to get long life. The selection of materials can be based on the nature, location and tissue type, which should be regenerated. Normally, a bone construct has its own requirements like osteo conduction properties, Tendency to mineralize, Rate of degradation and osteogenic differentiation properties. The best approach is to create regenerative medicine using suitable devices. This work focuses on developing the scaffold using 316L stainless steel fabricated with dual coating. The first layer of coating was made using Yttria Stabilized Zirconia by electrophoretic deposition. While the top second layer made as electro spun over 316L stainless steel . The electro spun made with β-Tricalcium phosphate (β-TCP) incorporated in PCL (Polycaprolactone). The process of electrospinning preferred to achieve porous surface. The bilayer scaffold performance was evaluated by surface morphology, bioactivity, bioresorbable and biodegradability with its cell adhesion capacity were studied. The results of X-ray diffraction reveal the presence of nanoparticle on the top layer of 316L stainless steel scaffold. The surface topography studies using Field Emission Scanning Electron Microscopy (FESEM) confirms more than 70 % porosity. The functional group present in YSZ/β-TCP/PCL composite bilayer on 316L SS were determined using FTIR. The developed bilayer coated 316L Stainless steel scaffolds further evaluated by invitro studies to confirm the cell adhesion capability. MG 63 cell line isolated from the bone and possess fibroblast morphology was used for the assay. The cells were cultured and exposed to the developed scaffold, the cultured cells were exposed to MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) and the reduction of MTT directly measures the cell viability and the color change read through spectrophotometer. The cell growth and proliferation confirm its cell adhesion property. This present study helps in drug delivery using the nano fibers incorporated with bioresorbable TCP. The presence of TCP on the top of electro spun layer substantially supports the osteo conductivity through mineralization and degradation property.