In vitro bioactivity studies of larnite and larnite/chitin composites prepared from biowaste for biomedical applications

Abstract

Larnite (Ca 2 SiO 4) was synthesized by the sol-gel combustion process by using raw eggshell powder as a calcium source and urea as a fuel. The main focus of this work is to convert biowaste into a biomedical material at a low-processing temperature. X-ray diffraction (XRD) pattern confirms the phase purity of the larnite and Fourier transform infrared (FTIR) spectra confirms the presence of characteristic functional groups of larnite. Scanning electron microscopy (SEM) image shows agglomerated particles with cauliflower-like morphology and energy dispersive X-ray spectroscopy (EDX) confirms the presence of the stoichiometric ratio of required elements. Atomic force microscope (AFM) images reveal the presence of pores on the surface of spherical particles. Larnite/chitin composites were fabricated into scaffold with different ratios of bioceramic to biopolymer (70:30, 80:20) to investigate the influence of the polymer content on the apatite formation ability in simulated body fluid (SBF) medium. XRD pattern and FTIR spectra of the scaffold immersed in SBF shows apatite deposition within 5 days. The deposition of hydroxyapatite (HAP) on the scaffold surface increases with the increase in polymer content of the composite.

Conversion of Biowaste into Larnite by Sol‐Gel Combustion Route for Biomedical Applications

“…The observed peaks for carbonate group might be due to the breakdown of carbon dioxide in silicate ceramics which causes the asymmetrical stretching vibrations. The vibrational bands obtained for single phasic larnite were in accordance with the previous reports [11,15,20,21,31] …”

“…Since, larnite peaks were observed as the major phase and HAp peak was emerged as a minor phase at around 2θ=31.87°. The previous reports indicated that nucleation of apatite layer after 5 th day and 7 th day on the surface of larnite [20,21] . Thus, the presence of higher calcium content in larnite stimulates the apatite nucleation on the surface at a very faster rate.…”

“…Choudhary et al turned up that the eggshell waste can be incorporated as effective raw material for obtaining the desired phase of larnite [15] . It was found that egg‐shell derived larnite synthesized by sol‐gel combustion method at 800 °C showed the HAp nucleation on the surface within five days of immersion in the SBF medium [20] . Besides, the carbonated HAp deposition was noticed on the surface of larnite nano‐powders only after 7 days of immersion [21] …”

3D printed porous β-Ca2SiO4scaffolds derived from preceramic resin and their physicochemical and biological properties

“…To date, β-Ca 2 SiO 4 scaffolds were prepared by conventional methods such as polyurethane foam templating [18] and porogen templating [30], which were not easy to control porous scaffolds with well pore interconnection, proper pore size, or high porosity [31,32]. 3D printing technique can control the architectures of porous scaffolds via computer-assisted design or computer-aided manufacturing.…”

Zirconia Incorporation in 3D Printed β-Ca2SiO4 Scaffolds on Their Physicochemical and Biological Property

“…A mixture of CaCO 3 and SiO 2 powders were added into polyurethane foam with different weight ratio, and porous β-Ca 2 SiO 4 with a regulated porosity (54.2% 83.4%) could be formed after heat treatment [6] . Other methods including porogen templating, gel-cast foaming and freeze drying have also been used to fabricate porous β-Ca 2 SiO 4 bioceramics [11][12][13] . However, such methods are not precise enough to control pore shape, size and interconnectivity [14] .…”