Physicochemical and in vitro bioactivity studies of bioactive glasses in the SiO2-CaO-MgO-P2O5, SiO2-Na2O-CaO-P2O5 and SiO2-Na2O-CaO-MgO-P2O5 systems

Glasses in the quaternary and quinary system SiO2-CaO-MgO-P2O5 (SCMP), SiO2-Na2O-CaO-P2O5 (SNCP) and SiO2-Na2O-CaO-MgO-P2O5 (SNCMP), have been prepared by using the sol-gel technique. Investigations of structural and bioactive properties of these glasses have been undertaken by using X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray Spectroscopy (EDS). The in vitro bioactivity was assessed by determining the changes in surface morphology and composition after soaking in simulated body fluid (SBF) for up to 30 days at 37°C. X-ray diffraction patterns indicated the formation of hydroxycarbonated apatite layer (HCA) after only one hour for SNCMP glass and after four days for SCMP and SNCP glasses. Furthermore, observed bands of FTIR spectra confirmed the growth of HCA layer during in vitro test.Moreover, the dissolution rate has been investigated using energy-dispersive X-ray spectroscopy. The observed EDS patterns confirmed the growth of HCA layer on all samples surfaces during in vitro analysis. On the one hand, we report the existence of Na2Ca2Si3O9 (that couple good mechanical strength with satisfactory biodegradability) as a single crystalline phase in the SNCP glass when calcined at 600°C. On the other hand, we have noticed that the coexistence of magnesium and sodium both enhanced the dissolution rate and hindered the crystallization in the SNCMP glass at 600°C.

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THE STUDY ON GRANTING BIOACTIVITY OF Ti ALLOY BY SURFACE TREATMENT

Surface Review and Letters ◽

10.1142/s0218625x1001362x ◽

2010 ◽

Vol 17 (02) ◽

pp. 153-157 ◽

Cited By ~ 1

Author(s):

N. R. HA ◽

Z. X. YANG ◽

G. C. KIM ◽

K. H. HWANG ◽

D. S. SEO ◽

...

Keyword(s):

Surface Treatment ◽

Body Fluid ◽

Surface Effect ◽

In Vitro Test ◽

Ti Alloy ◽

X Ray Diffraction ◽

X Ray ◽

Chemical Surface ◽

Vitro Test

Titanium alloys are superior of biocompatibility, mechanical properties and chemical stability. The biocompatibility of Ti alloy is related to the surface effect between human tissue and implant. Therefore, the purpose of this study is to investigate the bioactivity of Ti alloy by alkali and acid chemical surface treatment; and the biocompatibility of Ti alloy was evaluated by in vitro test. Higher bone-bonding ability and bioactivity of the substrate were obtained by the formation of apatite layers on the Ti alloy in simulated body fluid. The microstructures of apatite layer were investigated by scanning electron microscope (SEM) and the formed phases were analyzed with X-ray diffraction (XRD).

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In Vitro Study of Microplasma Sprayed Hydroxyapatite Coatings in Simulated Body Fluid

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.79-82.815 ◽

2009 ◽

Vol 79-82 ◽

pp. 815-818 ◽

Cited By ~ 1

Author(s):

Qiu Ying Zhao ◽

Ding Yong He ◽

Xiao Yan Li ◽

Jian Min Jiang

Keyword(s):

Simulated Body Fluid ◽

Body Fluid ◽

Carbonate Apatite ◽

In Vitro Test ◽

X Ray Diffraction ◽

X Ray ◽

Amorphous Phases ◽

Hydroxyapatite Coatings ◽

Vitro Test

Hydroxyapatite (HA) coatings were deposited onto Ti6Al4V substrate by microplasma spraying (MPS) in the current research. The morphology, phase compositions, and percentage of crystallinity of the coatings were characterized by means of scanning electron microscopy (SEM) and X-ray diffraction. An in vitro evaluation by soaking the coatings in simulated body fluid (SBF) for up to 14 days was conducted aiming at the evaluation of their bioactivity. Results from the present investigation suggest that microplasma sprayed HA coatings exhibited certain roughness, pores, and microcracks. Thermal decomposition existed in the coatings where HA, α-TCP，β-TCP, amorphous phases, and CaO-exclusive impurities were observed. The in vitro test indicated that HA coatings deposited by MPS possessed better bioactivity and stability. A layer of carbonate-apatite covered most of the coating surface, which did not exhibit significant spalling after incubation in SBF.

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Preparation of the Nano-Hydroxyapatite/Chitosan/Konjac Glucomannan Composite as a Novel Degradable Drug Delivery System

Materials Science Forum ◽

10.4028/www.scientific.net/msf.569.357 ◽

2008 ◽

Vol 569 ◽

pp. 357-360

Author(s):

Gang Zhou ◽

Yu Bao Li ◽

Soo Wohn Lee

Keyword(s):

Drug Delivery ◽

Drug Delivery System ◽

Delivery System ◽

Konjac Glucomannan ◽

In Vitro Test ◽

X Ray Diffraction ◽

X Ray ◽

Before And After ◽

Vitro Test

Nano-hydroxyapatite (n-HA)/chitosan (CS)/konjac glucomannan (KGM) composite was prepared by integrating composition and molding. Then, X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used to analyze the physical, chemical and degradable properties of the composite before and after in simulated body fluid (SBF). Moreover, study in vitro test for drug delivery revealed that the amount of released pentoxifylline (1-[5-oxohexyl]-3,7-dimethylxanthine)(PTX) reached a plateau and equaled 80% of the drug loaded in an implant. The newly develop n-HA/CS/KGM composite may serve as a good degradable biomaterial for implantable drug delivery system (IDDS) in bone tissue engineering.

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ANTIBACTERIAL AND BIOCOMPATIBILITY PROPERTIES OF NANO-SILVER/TITANIA THIN LAYER

International Journal of Modern Physics B ◽

10.1142/s021797921110196x ◽

2011 ◽

Vol 25 (27) ◽

pp. 3647-3653

Author(s):

R. EMADI ◽

K. RAEISSI

Keyword(s):

Antibacterial Effect ◽

In Vitro Test ◽

X Ray Diffraction ◽

Sem Images ◽

X Ray ◽

Spherical Structures ◽

Vitro Test ◽

And Staphylococcus Aureus ◽

Electrodeposition Of Silver

Ag/TiO2coating was prepared by anodizing the surface of Ti followed by electrodeposition of silver. By X-ray diffraction (XRD) analyses, that indicated the crystalline size of Ag deposit onto the oxidized surface of Ti was around 32 nm. Scanning electron microscopy (SEM) images of the oxidized surface with and without Ag deposit show that TiO2is formed uniformly but Ag deposit consisted of numerous spherical structures. The Escherichia coli and Staphylococcus aureus bacteria were utilized to test the antibacterial effect of Ag/TiO2coating which showed more than 99% of bacteria were killed after 24 h incubation. The results of in vitro test showed Ag/TiO2coating is also biocompatible.

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Sol-gel bioactive glass-ceramics Part II: Glass-ceramics in the CaO-SiO2-P2O5-MgO system

Open Chemistry ◽

10.2478/s11532-009-0014-2 ◽

2009 ◽

Vol 7 (3) ◽

pp. 322-327 ◽

Cited By ~ 8

Author(s):

Lachezar Radev ◽

Vladimir Hristov ◽

Irena Michailova ◽

Bisserka Samuneva

Keyword(s):

Sol Gel ◽

Glass Ceramics ◽

Static Condition ◽

Ceramic Materials ◽

Molar Ratio ◽

In Vitro Test ◽

X Ray Diffraction ◽

Vitro Test ◽

Good Agreement

AbstractCeramics, with basic composition based on the CaO-SiO2-P2O5-MgO system with different Ca+ Mg/P+Si molar ratio (R), were prepared via polystep sol-gel technique. The structure of the obtained ceramic materials has been studied by XRD, FTIR spectroscopy, and SEM. X-ray diffraction showed the presence of akermanite and HA for the sample with R = 1.68 and Mg substituted β-TCP and silicocarnotite for the sample with R = 2.16, after thermal treatment at 1200°C/2 h. The obtained results are in good agreement with FTIR. In vitro test for bioactivity in static condition proved that the carbonate containing hydroxyapatite (CO3HA) can be formed on the surface of the synthesized samples. CO3HA consisted of both A- and B-type CO 32− ions. SEM micrographs depicted different forms of HA particles, precipitated on the surface after soaking in 1.5 simulated body fluid (SBF).

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Influence of thermal treatment on the structure and in vitro bioactivity of sol-gel prepared CaO-SiO2-P2O5 glass-ceramics

Processing and Application of Ceramics ◽

10.2298/pac1403155r ◽

2014 ◽

Vol 8 (3) ◽

pp. 155-166 ◽

Cited By ~ 14

Author(s):

Lachezar Radev

Keyword(s):

Thermal Treatment ◽

Calcium Silicate ◽

Sol Gel ◽

Glass Ceramics ◽

In Vitro Test ◽

In Vitro Bioactivity ◽

X Ray ◽

Vitro Test ◽

Sbf Solution

Nowadays there is a substantial practical interest in the in vitro bioactivity of calcium silicate phosphate (CSP) glass-ceramics and carbonate apatite (CO3HA) formation on their surfaces after in vitro test in simulated body fluid (SBF). The main purpose of the presented article is the evaluation of the chemical composition of the gel with nominal composition 70.59 CaO:28.23 SiO2:1.18 P2O5 (mol.%) on the structure, crystallization behaviour and in vitro bioactivity in SBF solution for 14 and 28 days. The prepared glass-ceramics have been synthesized via a polystep sol-gel method. The structure of the obtaining samples was studied by X-ray diffraction (XRD) analysis, Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX). After thermal treatment of the samples XRD confirmed the presence of ?-Ca2SiO4 and Ca15(PO4)2(SiO4)6, and indicated that at 1500?C Ca15(PO4)2(SiO4)6 becomes predominant phase. FTIR revealed the presence of all characteristics bands for calcium silicate phosphate (CSP) bonds. SEM monitors the presence of particles with different morphology. After in vitro test in SBF, FTIR depicted that B-type carbonate containing hydroxyapatite (CO3HA) is preferentially formed on the immersed glass-ceramics. SEMof the precipitated layers showed the presence of HA spheres. The changes in SBF solution after soaking the samples were recorded by inductively coupled plasma atomic emission spectroscopy (ICP-AES).

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A Novel Hydroxyapatite Carrier for Enrichment of Hydrocarbon Degradation Bacteria

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.336-338.1914 ◽

2007 ◽

Vol 336-338 ◽

pp. 1914-1917

Author(s):

Lei Yang ◽

Zhen Yi Zhang ◽

Xiao Shan Ning ◽

Guang He Li

Keyword(s):

Activated Carbon ◽

Sol Gel ◽

Hydrocarbon Degradation ◽

Potential Candidate ◽

X Ray Diffraction ◽

X Ray ◽

Bacterial Enrichment ◽

Bet Method ◽

The One ◽

Scanning Electron

In this paper, a novel and highly efficient hydroxyapatite (HA) carrier for cultivating hydrocarbon degradation bacteria (HDB) is introduced. The HA particles synthesized through a sol-gel method and different heat treatments were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and BET method. The microbial amount and activities of HDB cultivated on HA carriers were quantitatively investigated in order to assess their enriching capabilities. The results showed that HA synthesized at 550°C and the one without calcination could enrich HDB 3 and 2 magnitude orders more than the activated carbon, respectively. Mechanisms of bacterial enrichment on HA and activated carbon were also studied, and it is believed that the high bioactivity and the surface morphology of HA were responsible for the efficient reproduction of HDB. It is concluded that HA is a potential candidate to replace the conventionally used activated carbon as a novel carrier applied in the filed of bioremediation for oil contaminated soil.

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A novel ceramic material with medical application

Processing and Application of Ceramics ◽

10.2298/pac0801019p ◽

2008 ◽

Vol 2 (1) ◽

pp. 19-22 ◽

Cited By ~ 6

Author(s):

Joanna Podporska ◽

Marta Błażewicz ◽

Barbara Trybalska ◽

Łukasz Zych

Keyword(s):

Body Fluid ◽

Crystallization Process ◽

Sol Gel ◽

Medical Application ◽

In Vitro Test ◽

Glass Crystallization ◽

Complex Shapes ◽

Different Temperatures ◽

Vitro Test

Until now the basic methods used in manufacturing of wollastonite have been chemical (melting together with glass crystallization process, chemical coprecipitation) and sol - gel methods. A new and promising way of wollastonite fabrication is controlled pyrolysis of polysiloxane precursors with inorganic fillers. Heat treatment of such mixtures leads to the formation of wollastonite-containing ceramics already at about 1000?C. This is a relatively inexpensive and efficient method which enables to obtain complex shapes of the samples. The aim of this work was to obtain sintered, wollastonite-containing bioceramics and determine its bioactive features. Samples were sintered at three different temperatures: 1000, 1100 and 1200?C. Then the bioactivity of the wollastonite-containing ceramics was investigated by the ?in vitro? test in simulated body fluid. On the basis of the achieved results, it can be assumed that the obtained material possesses bioactive features.

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Clinical Evaluation of an in Vitro Test for Radiosensitivity of Leukemic Lymphocytes

Blood ◽

10.1182/blood.v20.4.432.432 ◽

1962 ◽

Vol 20 (4) ◽

pp. 432-442 ◽

Cited By ~ 23

Author(s):

ROBERT SCHREK ◽

STANLEY L. LEITHOLD ◽

IRVING A. FRIEDMAN ◽

WILLIAM R. BEST

Keyword(s):

Survival Time ◽

Median Survival ◽

Median Survival Time ◽

Leukocyte Count ◽

In Vitro Test ◽

X Rays ◽

X Ray ◽

Leukocyte Counts ◽

Vitro Test

Abstract A recently developed slide-chamber method was used to test the radiosensitivity of blood lymphocytes from 80 patients with chronic lymphocytic or lymphosarcoma-cell leukemia. The objective of this study was to determine whether these in vitro tests on sensitivity to x-rays had any clinical significance. Two objective criteria were used to measure the clinical reactions of the leukemic patients. The first was the duration of survival of patients following the in vitro test. The second was the minimal leukocyte count of a patient following x-ray therapy; the minimal count was expressed as a percentage of the count before therapy. The in vitro radiosensitivity was measured by the 10 per cent survival time of lymphocytes irradiated with 1000 r. Blood lymphocytes from non-leukemic individuals were highly radiosensitive with indices of 1.1 to 2.2 days. In initial tests, the lymphocytes of 61 leukemic patients had the same high sensitivity to x-rays as lymphocytes from non-leukemic individuals. In contrast, the lymphocytes of 19 leukemic patients were radioresistant to irradiation with indices of 2.5 to 11 days. The 61 patients with radiosensitive lymphocytes had a median survival time of 22 months after the in vitro test. In contrast, the 19 patients with radioresistant lymphocytes had a median survival time of only 4 months. Clinical x-ray therapy caused a greater decline in leukocyte counts in patients with radiosensitive lymphocytes than in those with radioresistant cells. A significant index of 0.60 was obtained for the correlation of in vitro radiosensitivity of lymphocytes and the in vivo decrease in leukocyte counts of patients after x-ray therapy. It is concluded that an in vitro finding of radioresistant lymphocytes is correlated with a poor response of the leukocyte count to x-ray therapy and a short survival time of the patient.

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In vitro bioactivity of Polyurethane/85S Bioglass composite scaffolds

Open Chemistry ◽

10.2478/s11532-013-0273-9 ◽

2013 ◽

Vol 11 (9) ◽

pp. 1439-1446 ◽

Cited By ~ 6

Author(s):

Lachezar Radev ◽

Darina Zheleva ◽

Irena Michailova

Keyword(s):

Sol Gel ◽

Spherical Particles ◽

Polymerization Reaction ◽

In Vitro Test ◽

In Vitro Bioactivity ◽

Before And After ◽

Vitro Test ◽

Sbf Solution ◽

Static Conditions

AbstractIn the present work Polyurethane (PU)/Bioglass (BG) composite materials were synthesized with different content of BG (10 and 20 mol.%) as filler. The 85S Bioglass was synthesized via polystep sol-gel method. The chemical composition of BG is 85SiO2-10CaO-5P2O5 (wt.%). The synthesis of PU was carried out by a two-step polyaddition reaction. The 85S BG was added in situ during the polymerization reaction. In vitro bioactivity of the prepared composites was examined in the presence of 1.5 SBF for 7 days in static conditions. The structure of synthesized PU/BG composites before and after in vitro test was determined by XRD, FTIR and SEM. XRD of the samples before in vitro test proved that the phase of γCa2P2O7 in the PU/20BG is visible. FTIR revealed the presence of urethane bond between OH-(from BG) and NCO groups (from PU). Based on FTIR results after in vitro test in 1.5 SBF solutions, A/B-carbonate containing hydroxyapatite (CO3HA) was formed. XRD proved that HA was formed on the surface of the samples, but Ca2P2O7 does not undergo any changes in the 1.5 SBF solution. SEM depicted the nano-HA agglomerated in spherical particles after immersion in 1.5 SBF for 7 days.

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