scholarly journals Preparation of DNA/Gold Nanoparticle Encapsulated in Calcium Phosphate

2011 ◽  
Vol 2011 ◽  
pp. 1-7 ◽  
Author(s):  
Tomoko Ito ◽  
Koyuki Ibe ◽  
Tomohiro Uchino ◽  
Hiroyuki Ohshima ◽  
Makoto Otsuka
Keyword(s):  
Gene Therapy ◽  
Hyaluronic Acid ◽  
Calcium Phosphate ◽  
Simulated Body Fluid ◽  
Gold Nanoparticle ◽  
Body Fluid ◽  
Enzymatic Degradation ◽  
Dna Complexes ◽  
Dna Complex ◽  
Nanoparticle Complex

Biocompatible DNA/gold nanoparticle complex with a protective calcium phosphate (CaP) coating was prepared by incubating DNA/gold nanoparticle complex coated by hyaluronic acid in SBF (simulated body fluid) with a Ca concentration above 2 mM. The CaP-coated DNA complex was revealed to have high compatibility with cells and resistance against enzymatic degradation. By immersion in acetate buffer (pH 4.5), the CaP capsule released the contained DNA complex. This CaP capsule including a DNA complex is promising as a sustained-release system of DNA complexes for gene therapy.

IN-VITRO BEHAVIOUR OF BIPHASIC CALCIUM PHOSPHATE WITH DIFFERENT RATIO OF SILICA CONTENT IN SIMULATED BODY FLUID

2015 ◽  
Vol 23 (1) ◽  
pp. 1-14
Author(s):  
Sudirman Sahid ◽  
◽  
Nor Shahida Kader Bashah ◽  
Salina Sabudin ◽  
◽  
...  
Keyword(s):  
Calcium Phosphate ◽  
Simulated Body Fluid ◽  
Body Fluid ◽  
Biphasic Calcium Phosphate ◽  
Silica Content

Effect of Electrical Polarization on the Behavior of Bioactive Glass Containing MgO and B2O3 in SBF

2006 ◽  
Vol 309-311 ◽  
pp. 333-336
Author(s):  
Emiko Amaoka ◽  
Erik Vedel ◽  
Satoshi Nakamura ◽  
Yusuke Moriyoshi ◽  
Jukka I. Salonen ◽  
...  
Keyword(s):  
Calcium Phosphate ◽  
Simulated Body Fluid ◽  
Bioactive Glass ◽  
Body Fluid ◽  
Charged Surface ◽  
Depolarization Current ◽  
Electrical Polarization ◽  
Thermally Stimulated Depolarization Current ◽  
Thermally Stimulated Depolarization ◽  
Calcium Phosphate Precipitation

We investigated the electrical polarizability of MgO and B2O3 containing bioactive glass (MBG). The MBG material with good manufacturing properties but low bioactivity was electrically polarized at a high dc field. The electrical polarizability of MBG was evaluated by thermally stimulated depolarization current (TSDC) measurements and immersion in simulated body fluid (SBF). The early precipitation of calcium phosphate on the negatively charged surface of the treated MBG demonstrated the increased bioactivity of the material and confirmed its polarizability. It is suggested that the electrical interactions between the polarized MBG and ions in SBF promoted the formation of the calcium phosphate precipitation. Accordingly, the increased bioactivity of the MBG in SBF is suggested to demonstrate the conversion of MBG into electrovector ceramics by the polarization treatment.

scholarly journals Biphasic composite of calcium phosphate-based mesoporous silica as a novel bone drug delivery system

2019 ◽  
Vol 10 (2) ◽  
pp. 455-470 ◽  
Author(s):  
Magdalena Prokopowicz ◽  
Adrian Szewczyk ◽  
Adrianna Skwira ◽  
Rafał Sądej ◽  
Gavin Walker
Keyword(s):  
Drug Delivery ◽  
Calcium Phosphate ◽  
Simulated Body Fluid ◽  
Mesoporous Silica ◽  
Drug Delivery System ◽  
Delivery System ◽  
Body Fluid ◽  
Molecular Surface ◽  
Molar Ratio ◽  
Mineralization Potential

AbstractWe reported the new biphasic composites of calcium phosphate and mesoporous silica material (CaP@MSi) in the form of powders and pellets as a potential bone drug delivery system for doxycycline hydrochloride (DOX). The CaP@MSi powders were synthesized by cationic surfactant-templating method. The effects of 10, 20, and 30% CaP content in the CaP@MSi powders on the molecular surface structure, the cytotoxicity against osteoblast cells in vitro, and the mineralization potential in simulated body fluid were investigated. The CaP@MSi characterized by the highest mineralization potential (30% CaP content) were used for DOX adsorption and pelletization process. The CaP which precipitated in the CaP@MSi composites was characterized as calcium-deficient with the Ca:P molar ratio between 1.0 and 1.2. The cytotoxicity assays demonstrated that the CaP content in MSi increases osteoblasts viability indicating the CaP@MSi (30% CaP content) as the most biocompatible. The combination of CaP and MSi was an effective strategy to improve the mineralization potential of parent material. Upon immersion in simulated body fluid, the CaP of composite converted into the bone-like apatite. The obtained pellets preserved the mineralization potential of CaP@MSi and provided the prolonged 5-day DOX release. The obtained biphasic CaP@MSi composites seem to have an application potential as bone-specific drug delivery system.

Bioactivity Assessment of Apatite Nuclei-PVDF Composite Thin Films

2018 ◽  
Vol 782 ◽  
pp. 78-83
Author(s):  
Hasnat Zamin ◽  
Takeshi Yabutsuka ◽  
Shigeomi Takai
Keyword(s):  
Thin Films ◽  
Calcium Phosphate ◽  
Simulated Body Fluid ◽  
Body Fluid ◽  
Polyvinylidene Fluoride ◽  
Solution Casting ◽  
Casting Technique ◽  
Doctor Blade ◽  
Solution Casting Technique ◽  
Hydroxyapatite Formation

Particles of calcium phosphate were precipitated by raising the temperature and the pH of simulated body fluid (SBF) named Apatite Nuclei (AN). AN and polyvinylidene fluoride (PVDF) composites thin films with different weight percentages of AN in PVDF were fabricated by solution casting technique, using doctor blade method. In order to assess the bioactivity, the thin films were soaked in simulated body fluid (SBF). It was found that the film containing 30 wt.% of AN in PVDF actively induced hydroxyapatite formation in 3 days soaking period in SBF.

Biodegradable Bone Cement Using Calcium Phosphate Glass

2006 ◽  
Vol 309-311 ◽  
pp. 861-864 ◽  
Author(s):  
Byung Hyun Lee ◽  
Min Chul Kim ◽  
Kyoung Nam Kim ◽  
Kwang Mahn Kim ◽  
Seong Ho Choi ◽  
...  
Keyword(s):  
Weight Loss ◽  
Compressive Strength ◽  
Calcium Phosphate ◽  
Simulated Body Fluid ◽  
Dissolution Rate ◽  
Phosphate Glass ◽  
Body Fluid ◽  
Setting Time ◽  
Ageing Test ◽  
Dynamic Assay

In preliminary ageing test, the cement using only calcium phosphate glass as power phase cracked with 1 day in simulated body fluid because of high dissolution rate of the cement. We added 30 wt% of either β-TCP or HA to 70 wt% calcium phosphate glass as powder phase to control the dissolution rate of the cement and performed in vitro ageing test in simulated body fluid by dynamic protocol as well as static protocol to confirm the possibility of controlling. Adding either β-TCP or HA to the cement increases the setting time and decreases the compressive strength. In dynamic assay, the pH of extract is maintained over 7. However, pH decreased to around 5 in static assay. Therefore, weight loss by static protocol continuously increased for 14 days, while weight loss by dynamic protocol almost saturated. In XRD patterns of ageing cements, CaO peaks appeared. CaO peak was maximized most lately in dynamic assay of the cement adding HA and within 7 days, the cement adding HA showed higher weight loss. It is indicated that CaO formed in surface of the cement hinder the dissolution of the cement. In addition, compressive strength increased when the CaO peak was maximized.

STUDY OF NICKEL ION RELEASE IN SIMULATED BODY FLUID FROM C+-IMPLANTED NICKEL TITANIUM ALLOY

2016 ◽  
Vol 23 (05) ◽  
pp. 1650045 ◽  
Author(s):  
MUHAMMAD AHSAN SHAFIQUE ◽  
G. MURTAZA ◽  
SHAHZAD SAADAT ◽  
ZEESHAN ZAHEER ◽  
MUHAMMAD SHAHNAWAZ ◽  
...  
Keyword(s):  
Calcium Phosphate ◽  
Simulated Body Fluid ◽  
Body Fluid ◽  
Niti Alloy ◽  
Niti Shape Memory Alloy ◽  
Ion Release ◽  
Nickel Ion ◽  
Oxidation Layer ◽  
X Ray ◽  
Calcium Phosphate Precipitation

Nickel ion release from NiTi shape memory alloy is an issue for biomedical applications. This study was planned to study the effect of C[Formula: see text] implantation on nickel ion release and affinity of calcium phosphate precipitation on NiTi alloy. Four annealed samples are chosen for the present study; three samples with oxidation layer and the fourth without oxidation layer. X-ray diffraction (XRD) spectra reveal amorphization with ion implantation. Proton-induced X-ray emission (PIXE) result shows insignificant increase in Ni release in simulated body fluid (SBF) and calcium phosphate precipitation up to [Formula: see text][Formula: see text]ions/cm2. Then Nickel contents show a sharp increase for greater ion doses. Corrosion potential decreases by increasing the dose but all the samples passivate after the same interval of time and at the same level of [Formula: see text] in ringer lactate solution. Hardness of samples initially increases at greater rate (up to [Formula: see text][Formula: see text]ions/cm[Formula: see text] and then increases with lesser rate. It is found that [Formula: see text][Formula: see text]ions/cm2 ([Formula: see text] is a safer limit of implantation on NiTi alloy, this limit gives us lesser ion release, better hardness and reasonable hydroxyapatite incubation affinity.

Fabrication of Hydroxyapatite Microcapsule Containing Vitamin B12 for Sustained-Release

2014 ◽  
Vol 631 ◽  
pp. 326-331 ◽  
Author(s):  
Takeshi Yabutsuka ◽  
Kazuma Iwahashi ◽  
Hiroki Nakamura ◽  
Takeshi Yao
Keyword(s):  
Calcium Phosphate ◽  
Simulated Body Fluid ◽  
Sustained Release ◽  
Body Fluid ◽  
Fine Particles ◽  
Vitamin B ◽  
Hydroxyapatite Formation

When either the pH or temperature of simulated body fluid (SBF) are raised, fine particles of calcium phosphate are precipitated. We found that these fine particles actively induce hydroxyapatite formation from body fluid or SBF and named the particles Apatite Nuclei. In this study, we fabricated hollow hydroxyapatite microcapsules by using Apatite Nuclei. We inserted vitamin B12 in the hollow microcapsule and examined thesustained-release properties.

Biomimetic Mineralization and Bioactivity of Phosphorylated Chitosan

2005 ◽  
Vol 288-289 ◽  
pp. 429-432 ◽  
Author(s):  
Zhi Qing Chen ◽  
Quan Li Li ◽  
Quan Zen ◽  
Gang Li ◽  
Hao Bin Jiang ◽  
...  
Keyword(s):  
Calcium Phosphate ◽  
Simulated Body Fluid ◽  
Body Fluid ◽  
Crystal Nucleation ◽  
Osteoblast Proliferation ◽  
Biomimetic Mineralization ◽  
P Content ◽  
Proliferation And Differentiation ◽  
Nucleation Growth

Phosphorylated chitosans were synthesized as templates to manipulate hydroxyapatite (HA) crystal nucleation, growth and microstructure. Two kinds of insoluble phosphorylated chitosan were soaked in saturated Ca(OH)2 solution for 4 d and in 1.5× SBF (simulated body fluid) solutions for 14 d at 37 °C for biomimetic mineralization. A lower [P]-content of phosphorylated chitosan promoted greater mineralization than higher [P]-content. Phosphorylated chitosan inhibited osteoblast proliferation and differentiation in vitro, while calcium phosphate phosphorylated chitosan composites did not.

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