scholarly journals Morphology andIn VitroBehavior of Electrospun Fibrous Poly(D,L-lactic acid) for Biomedical Applications

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Toshihiro Inami ◽  
Yasuhiro Tanimoto ◽  
Masayuki Ueda ◽  
Yo Shibata ◽  
Satoshi Hirayama ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Biomedical Applications ◽  
Polymer Concentration ◽  
The Body ◽  
Solution Flow Rate ◽  
Apatite Formation ◽  
X Ray Diffraction ◽  
Solution Flow

This work describes the fabrication, optimization, and characterization of electrospun fibrous poly(D,L-lactic acid) (PDLLA) for biomedical applications. The influences of the polymer concentration of the electrospinning solution (5, 10, or 15 wt%) and the solution flow rate (0.1, 0.5, 1.0, or 2.0 mL/h) on the morphology of the obtained fibrous PDLLA were evaluated. Thein vitrobiocompatibility of two types of PDLLA, ester terminated PDLLA (PDLLA-R) and carboxyl terminated PDLLA (PDLLA-COOH), was evaluated by monitoring apatite formation on samples immersed in Hanks’ balanced salt (HBS) solution. 15 wt% polymer solution was the most beneficial for preparing a fibrous PDLLA structure. Meanwhile, no differences in morphology were observed for PDLLA prepared at various flow rates. Apatite precipitate is formed on both types of PDLLA only 1 day after immersion in HBS solution. After 7 days of immersion, PDLLA-COOH showed greater apatite formation ability compared with that of PDLLA-R, as measured by thin-film X-ray diffraction. The results indicated that the carboxyl group is effective for apatite precipitation in the body environment.

Extraction and Characterization of Natural Hydroxyapatite from Goat Bone for Biomedical Applications

2020 ◽  
Vol 1010 ◽  
pp. 573-578
Author(s):  
Sarfa Azian Ismail ◽  
Hasan Zuhudi Abdullah
Keyword(s):  
Calcination Temperature ◽  
Biomedical Applications ◽  
Extraction Process ◽  
Apatite Formation ◽  
X Ray Diffraction ◽  
X Ray ◽  
Shape Structure ◽  
Micron Size

Bioactive apatite, which is hydroxyapatite (HAP) with the chemical formula of Ca10(PO4)6(OH)2 have been extensively investigated for biomedical applications in bone and teeth implants due to its biocompatibility characteristics has similar physical-chemical characteristics with human bone. The issues to be highlighted here is to explore the potential of using food waste from goat bone to produce useful natural HAP. This study is to extract natural HAP powder from goat bone waste. The extraction process involved cleaning and boiling process, drying process, crushing, grinding and milling to obtain micron size powder of goat bone and joint. The sample then underwent a calcination process with 900°C, 1000°C, and 1100°C for goat bone and 900°C for goat joint with 3 hours holding time. The characteristic of produced HAP powder was characterised with Scanning Electron Microscope (SEM), Energy Dispersive X-ray Spectroscopy (EDS), X-ray Diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR). The in vitro testing of HAP completed by using Simulated Body Fluid (SBF) and SEM to observe the microstructure of apatite formation. The XRD and EDS results show the HAP crystallinity and Ca/P ratio increase with the increasing of calcination temperature for bone. The bone-like apatite formation appeared in the goat bone and joint sample with calcination temperature 900°C, 1000°C, and 1100°C. The optimum hydroxyapatite is from goat bone sample with calcination temperature 1100°C due to the apatite growth fully cover the surface of the sample with a needle shape structure of the cauliflower structure.

Characterization of Crystalline Hydroxyapatite Thin Coatings for Biomedical Applications

2007 ◽  
Vol 330-332 ◽  
pp. 525-528 ◽  
Author(s):  
Zhen Hong ◽  
Alexandre Mello ◽  
L. Luan ◽  
Marcos Farina ◽  
L.R. Andrade ◽  
...  
Keyword(s):  
Magnetron Sputtering ◽  
Biomedical Applications ◽  
Rf Magnetron Sputtering ◽  
Xrd Analysis ◽  
Hydroxyl Groups ◽  
X Ray Diffraction ◽  
Thin Coatings ◽  
Phosphate Carbonate

Crystalline hydroxyapatite thin coatings have been prepared using a novel opposing RF magnetron sputtering approach at room temperature. X-ray diffraction (XRD) analysis shows that all the principal peaks are attributable to HA, and the as-deposited HA coatings are made up of crystallites in the size range of 50-100nm. Fourier transform infrared spectroscopy (FTIR) studies reveal the existence of phosphate, carbonate and hydroxyl groups, suggesting that HA coatings are carbonated. Finally, in vitro cell culture experiments have demonstrated that murine osteoblast cells attach and grow well on the as-sputtered coatings. These results encourage further studies of hydroxyapatite thin coatings prepared by the opposing RF magnetron sputtering approach as a promising candidate for next-generation bioimplant materials.

Synthesis and Characterization of Sol-Gel Derived Hydroxyapatite-Bioglass Composite Nanopowders for Biomedical Applications

2012 ◽  
Vol 12 ◽  
pp. 51-57 ◽  
Author(s):  
S. Adibnia ◽  
Ali Nemati ◽  
Mohammad Hosseien Fathi ◽  
S. Baghshahi
Keyword(s):  
Electron Microscopy ◽  
Inductively Coupled Plasma ◽  
Biomedical Applications ◽  
Sol Gel ◽  
In Vitro Study ◽  
Apatite Formation ◽  
X Ray Diffraction ◽  
Inductively Coupled ◽  
Transmission Electron

The main purpose of this study is to prepare and characterize hydroxyapatite (HA)–10%wt bioglass (BG) composite nanopowders and its bioactivity. Composites of hydroxyapatite with synthesized bioglass are prepared at various temperatures. Suitable calcination temperature is chosen by evaluating of the phase composition. X-ray diffraction (XRD), Transmission electron microscopy (TEM) and Scanning electron microscopy (SEM) techniques are utilized to characterize the prepared nanopowders. The bioactivity of the prepared composite samples is evaluated in an in vitro study by immersion of samples in simulated body fluid (SBF) for predicted time. Fourier transformed infrared (FTIR) spectroscopy and inductively coupled plasma (ICP) are used for evaluation of apatite formation and the bioactivity properties. Results show that HA-BG composite nanopowders are successfully prepared without any decomposition of hydroxyapatite. The suitable temperature for calcination is 600°C and the particle size of hydroxyapatite is about 40-70 nm. The apatite phase forms after 14 days immersing of the samples in SBF. It could be concluded that this process can be used to synthesize HA-BG composite nanopowders with improved bioactivity which is much needed for hard tissue repair and biomedical applications.

Synthesis and characterization of multiphase bioactive glass-ceramics in the CaO–MgO–SiO2 system with B2O3 additive

2008 ◽  
Vol 23 (11) ◽  
pp. 2873-2879 ◽  
Author(s):  
Xianchun Chen ◽  
Yan Wei ◽  
Zhongbing Huang ◽  
Yunqing Kang ◽  
Guangfu Yin
Keyword(s):  
Bending Strength ◽  
Coefficient Of Thermal Expansion ◽  
Glass Ceramics ◽  
Nominal Composition ◽  
Apatite Formation ◽  
X Ray Diffraction ◽  
Cell Growth And Viability ◽  
Bonelike Apatite

A glass-ceramic (GC0) with nominal composition of 51.2% CaO–12.1% MgO–36.7% SiO2 (wt%) was synthesized. Then multiphase glass-ceramics of MGC1 and MGC2 were obtained by adding 1 and 2 wt% B2O3 to GC0 followed by thermal treatment. The bending strength of MGC1 was the highest, about 89.46 MPa, and the coefficient of thermal expansion was 10.67 × 10−6 °C−1, closer to that of Ti–6Al–4V alloy (10.03 × 10−6 °C−1). X-ray diffraction analysis confirmed that MGC1 was predominantly composed of akermanite, merwinite, and small amounts of dicalcium silicate crystalline phases. The bioactivity and cytocompatibility in vitro of MGC1 were detected by investigating the bonelike apatite-formation ability in simulated body fluid (SBF) and osteoblast morphology and viability. The results showed that MGC1 possessed bonelike apatite-formation ability in SBF and could release ionic products to significantly stimulate cell growth and viability. Furthermore, osteoblasts adhered and spread well on MGC1, indicating good bioactivity and potential cytocompatibility.

scholarly journals Injectable non-leaching tissue-mimetic bottlebrush elastomers as an advanced platform for reconstructive surgery

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Erfan Dashtimoghadam ◽  
Farahnaz Fahimipour ◽  
Andrew N. Keith ◽  
Foad Vashahi ◽  
Pavel Popryadukhin ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Reconstructive Surgery ◽  
Biomedical Applications ◽  
The Body ◽  
Surrounding Tissue ◽  
Curing Time ◽  
Materials Used ◽  
Significant Health

AbstractCurrent materials used in biomedical devices do not match tissue’s mechanical properties and leach various chemicals into the body. These deficiencies pose significant health risks that are further exacerbated by invasive implantation procedures. Herein, we leverage the brush-like polymer architecture to design and administer minimally invasive injectable elastomers that cure in vivo into leachable-free implants with mechanical properties matching the surrounding tissue. This strategy allows tuning curing time from minutes to hours, which empowers a broad range of biomedical applications from rapid wound sealing to time-intensive reconstructive surgery. These injectable elastomers support in vitro cell proliferation, while also demonstrating in vivo implant integrity with a mild inflammatory response and minimal fibrotic encapsulation.

scholarly journals A GREEN APPROACH FOR THE SYNTHESIS OF DRUG DELIVERY SYSTEM, MESOPOROUS SILICA GRAFTED ACRYLAMIDE –β- CYCLODEXTRIN COMPOSITE, FOR THE CONTROLLED RELEASE OF CURCUMIN

2018 ◽  
Vol 11 (9) ◽  
pp. 372
Author(s):  
Manohar D Mullassery ◽  
Noeline B Fernandez ◽  
Surya R ◽  
Diana Thomas
Keyword(s):  
Drug Delivery ◽  
Controlled Delivery ◽  
X Ray Diffraction ◽  
In Vitro Biocompatibility ◽  
Green Approach ◽  
Solvent Free Conditions ◽  
Good Biocompatibility ◽  
Biocompatibility Study

Objective: The scope of the present study was the preparation and characterization of a novel composite acrylamide β-cyclodextrin grafted 3-aminopropyltriethoxysilane bentonite (AMCD-g-APSB), for the controlled delivery of curcumin (CUR).Methods: AMCD-g-APSB, was synthesized by solvent-free conditions using microwave irradiation. The structure and surface morphology of the composite was established using Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, thermal analysis, etc.Results: The swelling percentage of the composite depends on both time and pH of the medium. The maximum swelling of the composite occurred at a pH of 7.4. The maximum drug encapsulation was occurring at a pH 3. About 96.5% of drug was loaded at pH 3. In vitro biocompatibility study was performed, and the result showed good biocompatibility of the composite in the concentration range 2.5–50 μg/ml.Conclusions: Drug delivery study of the composite proved that CUR could be successfully released in a controlled manner in the colon without much loses of the drug in the stomach.

scholarly journals Injectable Non-leaching Tissue-mimetic Bottlebrush Elastomers: A New Platform for Advancing Reconstructive Surgery

2020 ◽  
Author(s):  
Erfan Dashtimoghadam ◽  
Farahnaz Fahimipour ◽  
Andrew Keith ◽  
Foad Vashahi ◽  
Pavel Popryadukhin ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Reconstructive Surgery ◽  
Biomedical Applications ◽  
The Body ◽  
Surrounding Tissue ◽  
Curing Time ◽  
Materials Used ◽  
Significant Health

Abstract Current materials used in biomedical devices do not match tissue’s mechanical properties and leach various chemicals into the body. These deficiencies pose significant health risks that are further exacerbated by invasive implantation procedures. Herein, we leverage the brush-like polymer architecture to design and administer minimally invasive injectable elastomers that cure in vivo into leachable-free implants with mechanical properties matching the surrounding tissue. This strategy allows tuning curing time from minutes to hours, which empowers a broad range of biomedical applications from rapid wound sealing to time-intensive reconstructive surgery. These injectable elastomers support in vitro cell proliferation, while also demonstrating in vivo implant integrity with a mild inflammatory response and minimal fibrotic encapsulation.

Apatite-Forming Ability of Organic-Inorganic Hybrids Prepared from Calcium Silicate and Glucomannan

2007 ◽  
Vol 361-363 ◽  
pp. 567-570
Author(s):  
Yasuyuki Morita ◽  
Toshiki Miyazaki ◽  
Eiichi Ishida ◽  
Chikara Ohtsuki
Keyword(s):  
Calcium Silicate ◽  
Body Fluid ◽  
Organic Polymer ◽  
Apatite Formation ◽  
X Ray Diffraction ◽  
Electron Microscopic ◽  
Living Body ◽  
Bioactive Ceramics ◽  
Previously Treated

So-called bioactive ceramics are used for bone-repairing owing to attractive features such as direct bone-bonding in living body. However, there is limitation on clinical applications due to their inappropriate mechanical properties performances such as higher brittleness and lower fracture toughness than natural bone. To overcome this problem, hybrid materials have been developed by modification of calcium silicate, that is basic component of bioactive ceramics, with organic polymer. It is known that bioactive ceramics bond to bone through bone-like apatite layer which is formed on their surfaces by chemical reaction with body fluid. We attempted preparation of bioactive organic-inorganic hybrids from Glucomannan that is a kind of complex polysaccharide, and calcium silicate. Hybrids were prepared from glucomannan and tetraethoxysilane (TEOS). They were treated with 1M (=mol·m-3) CaCl2 aqueous solution for 24 hours. Then ability of apatite formation on the hybrids was examined in vitro using simulated body fluid (SBF, Kokubo solution). Surface structure of the specimens was examined by thin-film X-ray diffraction (TF-XRD), scanning electron microscopic (SEM) observation. The hybrids with TEOS:Glucomannan= 1:1 to 4:1 in mass ratio formed the apatite in SBF within 3 or 7 d, when they were previously treated with CaCl2 solution.

scholarly journals Molecular and functional characterization of somatostatin-type signalling in a deuterostome invertebrate

Open Biology ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 200172
Author(s):  
Ya Zhang ◽  
Luis Alfonso Yañez Guerra ◽  
Michaela Egertová ◽  
Cleidiane G. Zampronio ◽  
Alexandra M. Jones ◽  
...  
Keyword(s):  
Functional Characterization ◽  
The Body ◽  
Pharmacological Characterization ◽  
Cardiac Stomach ◽  
Physiological Processes ◽  
Pharmacological Tests ◽  
The Central Nervous System

Somatostatin (SS) and allatostatin-C (ASTC) are structurally and evolutionarily related neuropeptides that act as inhibitory regulators of physiological processes in mammals and insects, respectively. Here, we report the first molecular and functional characterization of SS/ASTC-type signalling in a deuterostome invertebrate—the starfish Asterias rubens (phylum Echinodermata). Two SS/ASTC-type precursors were identified in A. rubens (ArSSP1 and ArSSP2) and the structures of neuropeptides derived from these proteins (ArSS1 and ArSS2) were analysed using mass spectrometry. Pharmacological characterization of three cloned A. rubens SS/ASTC-type receptors (ArSSR1–3) revealed that ArSS2, but not ArSS1, acts as a ligand for all three receptors. Analysis of ArSS2 expression in A. rubens using mRNA in situ hybridization and immunohistochemistry revealed stained cells/fibres in the central nervous system, the digestive system (e.g. cardiac stomach) and the body wall and its appendages (e.g. tube feet). Furthermore, in vitro pharmacological tests revealed that ArSS2 causes dose-dependent relaxation of tube foot and cardiac stomach preparations, while injection of ArSS2 in vivo causes partial eversion of the cardiac stomach. Our findings provide new insights into the molecular evolution of SS/ASTC-type signalling in the animal kingdom and reveal an ancient role of SS-type neuropeptides as inhibitory regulators of muscle contractility.

scholarly journals Synthesis and characterization of silver nanoparticle-decorated cobalt nanocomposites (Co@AgNPs) and their density-dependent antibacterial activity

2019 ◽  
Vol 6 (5) ◽  
pp. 182135 ◽  
Author(s):  
Zakia Kanwal ◽  
Muhammad Akram Raza ◽  
Saira Riaz ◽  
Saher Manzoor ◽  
Asima Tayyeb ◽  
...  
Keyword(s):  
Metallic Nanoparticles ◽  
Cobalt Acetate ◽  
X Ray Diffraction ◽  
Characteristic Analysis ◽  
Density Dependent ◽  
Antibacterial Performance ◽  
Magnetic Cores ◽  
Low Concentrations

Magnetic cores loaded with metallic nanoparticles can be promising nano-carriers for successful drug delivery at infectious sites. We report fabrication, characteristic analysis and in vitro antibacterial performance of nanocomposites comprising cobalt cores (Co-cores) functionalized with a varied concentration of silver nanoparticles (AgNPs). A two-step polyol process synchronized with the transmetalation reduction method was used. Co-cores were synthesized with cobalt acetate, and decoration of AgNPs was carried out with silver acetate. The density of AgNPs was varied by changing the amount of silver content as 0.01, 0.1 and 0.2 g in the synthesis solution. Both AgNPs and Co-cores were spherical having a size range of 30–80 nm and 200 nm to more than 1 µm, respectively, as determined by scanning electron microscopy. The metallic nature and face-centred cubic crystalline phase of prepared nanocomposites were confirmed by X-ray diffraction. Biocompatibility analysis confirmed high cell viability of MCF7 at low concentrations of tested particles. The antibacterial performance of nanocomposites (Co@AgNPs) against Escherichia coli and Bacillus subtilis was found to be AgNPs density-dependent, and nanocomposites with the highest AgNPs density exhibited the maximum bactericidal efficacy. We therefore propose that Co@AgNPs as effective drug containers for various biomedical applications.

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