Substituted hydroxyapatites for biomedical applications: A review

Three-dimensional printed biomaterials used as personalized tissue substitutes have the ability to promote and enhance regeneration in areas of defected tissue. The challenge with 3D printing for bone tissue engineering remains the selection of a material with optimal rheological properties for printing in addition to biocompatibility and capacity for uniform cell incorporation. Hydrogel biomaterials may provide sufficient printability to allow cell encapsulation and bioprinting of scaffolds with uniform cell distribution. In this study, a novel alginate-polyvinyl alcohol (PVA)-hydroxyapatite (HA) hydrogel formulation with optimal rheological properties for 3D bioprinting of mouse calvaria 3T3-E1 (MC3T3) cells into scaffolds of high shape fidelity has been developed. A systematic investigation was conducted to determine the effect of varying concentrations of alginate, phosphate, calcium, and the PVA-HA suspension in the formulation on the resulting viscosity and thus printability of the hydrogel. HA, the main mineral component in natural bone, was incorporated into the hydrogel formulation to create a favorable bone-forming environment due to its excellent osteoconductivity. Degradation studies in α-MEM cell culture media showed that the 3D printed alginate-PVA-HA scaffolds remained in-tact for 14 days. MC3T3 cells were well distributed and encapsulated throughout the optimal hydrogel formulation and expressed high viability through the completion of the 3D printing process. Thus, the development of this novel, osteoconductive, biodegradable, alginate-PVA-HA formulation and its ability to 3D bioprint tissue engineered scaffolds make it a promising candidate for treating personalized bone defects. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 1457-1468, 2017.

Development of a novel alginate-polyvinyl alcohol-hydroxyapatite hydrogel for 3D bioprinting bone tissue engineered scaffolds.

Fabrication and characterization of novel nano-biocomposite scaffold of chitosan-gelatin-alginate-hydroxyapatite for bone tissue engineering.

Bone tissue engineering has emerged as one of the most indispensable approaches to address bone trauma in the past few decades. This approach offers an efficient and a risk-free alternative to autografts and allografts by employing a combination of biomaterials and cells to promote bone regeneration. Hydroxyapatite (HA) is a ceramic biomaterial that mimics the mineral composition of bones and teeth in vertebrates. HA, commonly produced via several synthetic routes over the years has been found to exhibit good bioactivity, biocompatibility, and osteoconductivity under both in vitro and in vivo conditions. However, the brittle nature of HA restricts its usage for load bearing applications. To address this problem, HA has been used in combination with several polymers in the form of biocomposite implants to primarily improve its mechanical properties and also enhance the implants' overall performance by simultaneously exploiting the positive effects of both HA and the polymer involved in making the biocomposite. This review article summarizes the past and recent developments in the evolution of HA-polymer biocomposite implants as an "ideal" biomaterial scaffold for bone regeneration. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 2046-2057, 2018.

Hydroxyapatite-polymer biocomposites for bone regeneration: A review of current trends.

Nano sized semiconductor photocatalysts have a great scope for removal of large organic molecules like dyes and pesticides in an eco-friendly and sustainable manner. The photocatalytic decomposition of dyeing industrial wastewater produces negligible amount of solid by products. The problem associated with the existing catalysts are, their high band gap. Doping one catalyst with other suitable metals and metal oxides will enhance the efficiency of the photocatalyst and also makes the catalyst to be active in the visible region. The photocatalytic activity of the composite catalysts were highly improved through the modification in the crystallinity, micro structures, band gap, morphology, particle size and the surface area of the catalyst. This paper reviews the recent developments in the synthesis and application of composite photocatalysts. The role of synthetic pathways on the structure and activity of composite catalyst derived from TiO2, CdS, WO3, SnS and ZnO were analyzed. This paper will be more helpful for the scientists working in the field of nano sized photocatalysis.

Review on the photocatalytic activity of various composite catalysts

Development of nanocomposites based on hydroxyapatite/ sodium alginate: Synthesis and characterisation

Synthesis, spectral, thermal, mechanical and structural characterization of NLO active organic salt crystal: 3,5-Dimethylpyrazolium-3-Nitrophthalate

Nanohydroxyapatite–chitosan–gelatin polyelectrolyte complex with enhanced mechanical and bioactivity

Synthesis, structural, thermal, mechanical, second harmonic generation efficiency and laser damage threshold studies of 4-dimethylaminopyridinium-3,5-dicarboxybenzoate trihydrate single crystal

Synthesis, growth, characterisation and laser damage threshold studies of N,N-dimethylanilinium-3-carboxy-4-hydroxybenzenesulphonate crystal: An efficient SHG material for electro-optic applications

M. Rajkumar

Papers

Development of nanocomposites based on hydroxyapatite/ sodium alginate: Synthesis and characterisation

Synthesis, spectral, thermal, mechanical and structural characterization of NLO active organic salt crystal: 3,5-Dimethylpyrazolium-3-Nitrophthalate

Nanohydroxyapatite–chitosan–gelatin polyelectrolyte complex with enhanced mechanical and bioactivity

Synthesis, structural, thermal, mechanical, second harmonic generation efficiency and laser damage threshold studies of 4-dimethylaminopyridinium-3,5-dicarboxybenzoate trihydrate single crystal

Synthesis, growth, characterisation and laser damage threshold studies of N,N-dimethylanilinium-3-carboxy-4-hydroxybenzenesulphonate crystal: An efficient SHG material for electro-optic applications