No abstract

In the present investigation, the natural cellulose was extracted from Luffa cylindrica vegetable sponge by chemical modification. Both chemically modified and unmodified Luffa was characterized by Fourier‐transform infrared spectroscopy (FTIR), X‐ray powder diffraction (XRD), scanning electron microscopy (SEM), and energy‐dispersive X‐ray spectroscopy. The chemically modified cellulose was used for the preparation of a nanofibrous scaffold using the electrospinning method. In order to achieve the uniform and bead free fibers with desired fiber diameter the parameters such as applied voltage, tip to collector distance, solution concentration were optimized. Different ratio of hydroxyapatite (HAP): polylactic acid (PLA) such as 40:60, 50:50, 60:40, and 70:30 have been selected for the current evaluation and was compared with HAP‐treated cellulose (TC)‐PLA. With the increase in the concentration of HAP in the polymeric network, the diameter of the fiber was found to be thin with the high electric field. The functional group, phase formation and dielectric and mechanical properties of the developed nanofiber have been characterized by FTIR, XRD, mechanical property measurements, and SEM. From the results, we observed that the polymer composite developed with the ratio of 70:30 produces a bead free product with enhanced mechanical and bioactivity property by the formation of hydroxy carbonated apatite layer on the surface. All the nanofibrous scaffold fabricated with and without modification have shown good Cyto compatibility on MG‐63 Osteoblast cell lines at 48 hr. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 610–620, 2019.

Cancellous bone region of the human native bone has the potential to bear significant mechanical loads. However, due to the following parameters such as low trabecular volume, more porosity, less thickness and more interconnectivity, cancellous bone is accessible to damage in accidents or when aging. This research led to the effective fabrication and engineering of cancellous region of the bone for its application in reconstruction or filling of bone voids after resection of large tumor mass. Scaffolds containing hydroxyapatite (HAp), polyvinyl alcohol (PVA) and polyvinyl pyrrolidone (PVP) (5% polymer and HAp concentrations) at different HAp: polymer composite ratios (50:50, 70:30 and 80:20), were fabricated by freeze–drying method using only water as solvent and ribose as crosslinker for the scaffolds. The fabricated scaffolds were characterized for its mechanical (compressive) strength, chemical properties using FT‐IR and XRD analyses, swelling and degradation studies, confirmation of mineralization process by immersion in simulated body fluid (SBF) for 7, 15 and 30 days, morphological analysis using scanning electron microscopy (SEM), and biocompatibility properties by performing MTT analysis. From the combined interpretation of the above mentioned tests, it was proven that 80:20 ratio of HAp to polymers was found to be the most suitable scaffold in terms of its optimal properties for its use as bone graft material for trabecular bone. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 3267–3274, 2018.

The research on extracellular matrix (ECM) is new and developing area that covers cell proliferation and differentiation and ensures improved cell viability for different biomedical applications. Extracellular matrix not only maintains biological functions but also exhibits properties such as tuned or natural material degradation within a given time period, active cell binding and cellular uptake for tissue engineering applications. The principal objective of this study is classified into two categories. The first phase is optimization of various electrospinning parameters with different concentrations of HAP-HPC/PLA(hydroxyapatite-hydroxypropylcellulose/poly lactic acid). The second phase is in vitro biological evaluation of the optimized mat using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) assay for bone regeneration applications. Conductivity and dielectric constant were optimized for the production of thin fiber and bead free nanofibrous mat. With this optimization, the mechanical strength of all compositions was found to be enhanced, of which the ratio of 70:30 hit a maximum of 9.53 MPa (megapascal). Cytotoxicity analysis was completed for all the compositions on MG63 cell lines for various durations and showed maximum cell viability on 70:30 composition for more than 48 hrs. Hence, this investigation concludes that the optimized nanofibrous mat can be deployed as an ideal material for bone regenerative applications. In vivo study confirms the HAP-HPC-PLA sample shows more cells and bone formation at 8 weeks than 4 weeks.

In present work, the composites of hydroxyapatite with polyvinyl alcohol (PVA) and polyvinyl pyrrolidone (PVP) were prepared and analyzed for its biodegradability and hemocompatibilty. The individual and the combined combination of polymers with hydroxyapatite (HAP-PVA, HAP-PVP and HAP/PVA-PVP) were characterized by FT-IR, XRD, SEM-EDAX and TGA-DSC analysis. The crystallinity and functional groups of hydroxyapatite (HAP) was confirmed by XRD and FT-IR analysis. The SEM analysis displayed rod shaped morphology and the formation of apatite layer was confirmed by simulated body fluid (SBF) immersion. The Ca/P ratio of the SBF immersed composite was found to be increased to 1.71. This reveals that the polymer in the composite acts as a nucleating site for the development of carbonated hydroxyapatite which chemical composition resembles with natural bone. The hemolysis rate for the composite consisting of HAP/PVA-PVP was found to be less than 3% than the composite consisting of HAP with PVP. Based on these results, it can be concluded that the HAP/PVA-PVP nanocomposite offers superior alternatives in the field of biomedicines.