Monetite addition into gelatin based freeze-dried scaffolds for improved mechanical and osteogenic properties

Abstract

This study was aimed at fabricating monetite nanoparticles impregnated gelatin based composite scaffold to improve chemical, mechanical and osteogenic properties. Scaffolds were fabricated using freeze drying technique of the slurry containing varying proportion of gelatin and monetite. The lyophilized scaffolds were cross-linked with 0.25 wt% glutaraldehyde (GTA) solution to obtain 3D interconnected porous microstructure with improved mechanical strength and stability in physiological environment. The fabricated scaffolds possessed > 80% porosity having 3D interconnected pore size distribution varying between 65–270 μm as evident from Field emission scanning electron microscopy (FE-SEM) analysis. Average pore size of the prepared scaffold decreased with monetite addition as reflected in values of 210 m for pure gelatin GM0 scaffold and 118 μm registered by GM20 scaffold. On increase in monetite content upto 20 wt% of total polymer concentration, compressive strength of the prepared scaffolds was increased from 0.92 MPa in pure gelatin based GM0 to 2.43 MPa in GM20. Upto 20 wt% of monetite reinforced composite scaffolds exhibited higher bioactivity as compared to that observed in pure gelatin based GM0 scaffold. SBF study and alizarin red assays confirmed higher bio-mineralization ability of GM20 as compared to that exhibited by GM0. Human preosteoblast cells (MG-63) revealed higher degree of fillopodia and lamellopodia extensions and excellent spreading behavior to anchor with GM20 matrix as compared to that onto GM10, GM0. MTT assay and alkaline phosphatase (ALP) staining study indicated that MG-63 cells found more conducive environment to proliferate and subsequently differentiate into osteoblast lineage when exposed to GM20 scaffolds rather than to GM10, GM0, and. This study revealed that upto 20 wt% monetite addition in gelatin could improve the performance of prepared scaffolds and serve as an efficient candidate to repair and regenerate bone tissues at musculoskeletal defect sites.