The present study focused on the synthesis of calcium magnesium silicate (akermanite, Ca 2 MgSi 2 O 7 ) using eggshell biowaste (as calcium source), magnesium nitrate and tetraethyl orthosilicate (TEOS) as starting materials. Sol-gel combustion method was adopted to obtain calcium magnesium silicate. Citric acid was used as a fuel (reducing agent) and nitrate ions present in the metal nitrates acts as an oxidizing agent during combustion process. The characterization of synthesized calcium magnesium silicate was carried out by powder X-ray diffraction (XRD), Fourier transform infrared (FTIR) and scanning electron microscopy (SEM) techniques. Calcium magnesium silicate crystallite size was observed in nano regime which can effectively mimic natural bone apatite composition. In-vitro bioactivity was investigated by immersing calcium magnesium silicate pellet in simulated body fluid (SBF) for three weeks. Results show effective deposition of crystallized hydroxyapatite (HAP) layer on its surface and predicting its possibilities for applications in hard tissue regeneration. © 2015 The Ceramic Society of Japan and the Korean Ceramic Society.

Sasikumar S

Department of Chemistry

School of Advanced Sciences

Vellore Campus

Choudhary R

Koppala S

Fulltext

Vellore Institute of Technology (VIT) is a private university located in&nbsp;Tamil Nadu, India. Founded in 1984, as Vellore Engineering College, the institution offers 20 undergraduate, 34 postgraduate, four integrated and four research programs. It has campuses in Vellore, Amravati, Bhopal and Chennai.

VIT is one of the top ranked private universities in India according to NIRF, THE and QS Rankings.&nbsp;Govt. of India has recognized&nbsp;VIT, Vellore as an&nbsp;Institution of Eminence. This has allowed VIT to take independent quality initiatives and move up in world ranking.

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VIT University

Journal of Asian Ceramic Societies

It has been demonstrated that nanocrystalline forsterite powder synthesised using urea as a fuel in sol-gel combustion method had produced a pure forsterite (FU) and possessed superior bioactive characteristics such as bone apatite formation and antibacterial properties. In the present study, 3D-scaffold was fabricated using nanocrystalline forsterite powder in polymer sponge method. The FU scaffold was used in investigating the physicochemical, biomechanics, cell attachment, in vitro biocompatibility and osteogenic differentiation properties. For physicochemical characterisation, Fourier-transform infrared spectroscopy (FTIR), Energy dispersive X-ray (EDX), X-ray diffraction (XRD), Raman spectroscopy, X-ray photoemission spectrometer (XPS) and Brunauer-Emmett-Teller (BET) were used. FTIR, EDX, XRD peaks and Raman spectroscopy demonstrated correlating to FU. The XPS confirmed the surface chemistry associating to FU. The BET revealed FU scaffold surface area of 12.67 m 2 /g and total pore size of 0.03 cm 3 /g. Compressive strength of the FU scaffold was found to be 27.18 ± 13.4 MPa. The human bone marrow derived mesenchymal stromal cells (hBMSCs) characterisation prior to perform seeding on FU scaffold verified the stromal cell phenotypic and lineage commitments. SEM, confocal images and presto blue viability assay suggested good cell attachment and proliferation of hBMSCs on FU scaffold and comparable to a commercial bone substitutes (cBS). Osteogenic proteins and gene expression from day 7 onward indicated FU scaffold had a significant osteogenic potential (p&lt;0.05), when compared with day 1 as well as between FU and cBS. These findings suggest that FU scaffold has a greater potential for use in orthopaedic and/or orthodontic applications. © 2019 Krishnamurithy et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

PLOS ONE

The physicochemical and biomechanical profile of forsterite and its osteogenic potential of mesenchymal stromal cells

This study presents different fuels (Glycine and Urea) that can be used to synthesize nanocrystalline forsterite by the sol-gel combustion method. The weight change of precursor during thermal treatment was studied by thermo-gravimetric analysis (TGA). Pure forsterite was characterized by heating microscopy, Fourier transform infrared spectroscopy, X-ray Diffraction, Brunauer-Emmett-Teller, Scanning Electron Microscopy, and Energy dispersive X-ray spectroscopy. The HAP (hydroxyapatite) deposition ability, degradation and dissolution behaviour of forsterite was examined in simulated body fluid (SBF). The combusted forsterite precursor showed distinct thermal behaviour for each fuel when analyzed by heating microscopy. BET analysis showed that the particle size of forsterite synthesized using glycine was 28 nm, specific surface area 65.11 m2/g and average pore diameter 16.4 nm while using urea 1.951 μm, 0.939 m2/g, and 30.5 nm are the respective parameters. The dissolution of forsterite pointed to the consumption of Ca and P ions from SBF, the negligible release of Si ion into the SBF and these ionic interactions with SBF can be altered as per the material properties. The forsterite showed good antibacterial activity against S. aureus but lower activity against E. coli. The bactericidal activity of forsterite indicated that it can be used to inhibit biofilm formation in dental, bone implants and bacterial infection during surgical operations. © 2017 Elsevier B.V.

Materials Science and Engineering: C

Preparation of nanocrystalline forsterite by combustion of different fuels and their comparative in-vitro bioactivity, dissolution behaviour and antibacterial studies

Diopside was synthesized from biowaste (Eggshell) by sol-gel combustion method at low calcination temperature and the influence of two different fuels (urea, l-alanine) on the phase formation temperature, physical and biological properties of the resultant diopside was studied. The synthesized materials were characterized by heating microscopy, FTIR, XRD, BET, SEM and EDAX techniques. BET analysis reveals particles were of submicron size with porosity in the nanometer range. Bone-like apatite deposition ability of diopside scaffolds was examined under static and circulation mode of SBF (Simulated Body Fluid). It was noticed that diopside has the capability to deposit HAP (hydroxyapatite) within the early stages of immersion. ICP-OES analysis indicates release of Ca, Mg, Si ions and removal of P ions from the SBF, but in different quantities from diopside scaffolds. Cytocompatability studies on human bone marrow stromal cells (hBMSCs) revealed good cellular attachment on the surface of diopside scaffolds and formation of extracellular matrix (ECM). This study suggests that the usage of eggshell biowaste as calcium source provides an effective substitute for synthetic starting materials to fabricate bioproducts for biomedical applications. © 2016 Elsevier B.V. All rights reserved.

In-vitro bioactivity, biocompatibility and dissolution studies of diopside prepared from biowaste by using sol–gel combustion method

Materials Research Express

Sol gel combustion derived monticellite bioceramic powders for apatite formation ability evaluation

Nanocrystalline wollastonite was produced by sol-gel combustion method by using glycine as a fuel. The obtained powders were characterized by Fourier transform infrared spectroscopy (FTIR), powder X-ray diffraction (XRD) and scanning electron microscopy (SEM). The functional groups were identified by FTIR spectra and the XRD pattern reveals the formation of pure wollastonite phase. The SEM images reveal that the wollastonite particles are agglomerated and possess porous flakes-like morphology. The average particle size of the wollastonite particle observed from SEM images is found to be in the range of 44-111 nm. In vitro bioactivity characteristics of wollastonite were studied by immersing the prepared wollastonite scaffold in simulated body fluid (SBF) solution and the results indicate good bioactivity of wollastonite. © 2013 © 2013 The Indian Ceramic Society.

Transactions of the Indian Ceramic Society

Sol-Gel Combustion Synthesis of Nanocrystalline Wollastonite by Using Glycine as a Fuel and Itsin vitroBioactivity Studies

Wollastonite is a bioactive material (molecular formula of CaSiO3) that belongs to the class of calcium silicate. It is widely used as a bone regenerative material and as a drug delivery carrier due to its high bioactivity and biocompatibility. A novel sol-gel combustion synthesis has been adopted by using sucrose as a fuel and nitric acid as an oxidizer to synthesize wollastonite. Calcium nitrate and tetraethyl orthosilicate were taken as the source of calcium and silicate. The obtained powders were characterized by powder X-ray diffraction to check the phase formation and Fourier transform infrared (FT-IR) spectroscopy for the identification of the characteristic functional group. The average particle size calculated by using Scherer's formula is 51.7 nm, and the lattice parameter values are found to be a = 15.4301 Å, b = 7.3242 Å, and c = 7.017 Å. The phase transformation studies were carried out by using a thermogravimetric analyzer. The morphology of the pure wollastonite was imaged by using scanning electron microscopy and atomic force microscopy; the images shows irregular spheroid-shaped particles. © 2013 Copyright Taylor and Francis Group, LLC.

Combustion Science and Technology

Preparation and Phase Evolution of Wollastonite by Sol-Gel Combustion Method Using Sucrose as the Fuel

Calcium hydroxyapatite (Ca10(PO4)6(OH)2) has been synthesized in short duration by rapid solution combustion by employing different fuels. Calcium nitrate was taken as source of calcium and diammonium hydrogen phosphate served as the source of phosphate ions. Citric acid, tartaric acid, sucrose, glycine and urea were used as the fuels and nitrate ions and nitric acid were used as oxidizers. The influence of fuels on the morphology of the phase formed was studied. Results of the studies by powder X-ray diffraction and Fourier-transform infrared spectroscopy showed the formation of hydroxyapatite as a major phase for all the fuels. The thermal analysis of the decomposed precursor showed variation in heat content for different fuels. Scanning electron microscopy showed different morphologies of the products obtained by different fuels. Chemical analyses to determine the Ca:P atomic ratio in synthesized ceramics showed that the ratio was 1:1.66. © 2010 The Chinese Society for Metals.

Journal	Journal of Asian Ceramic Societies
Publisher	Informa UK Limited
ISSN	21870764
Open Access	Yes