Chitosan based hydrogel assisted spongelike calcium phosphate mineralization for in-vitro BSA release

Calcium phosphate has been the point of interest for in vitro gene delivery for many years because of its biocompatibility and straight forward application. However, there are some limitations regarding in vivo administration of these particles mostly because of vast agglomeration of the particles and lack of strong bond between the particles and pDNA. We introduced a simple single step method to functionalize calcium phosphate nanoparticles with Aminosilanes having a different number of amine groups. The nanoparticles were characterized chemically and structurally and their toxicity and interaction with pDNA were studied as well. Results revealed that different crystalline phase of calcium phosphate nanoparticles (Brushite and Hydroxyapatite) with a size below 150 nm were prepared, depending on conditions of synthesis and phase, each with a narrow size distribution. The aminosilane agents caused oriented nucleation and growth of crystallites and can decrease the pH for producing hydroxyapatite phase. The phenomenon could be revealed with the presence of anisotropy in the structure of synthesized hydroxyapatite. The number of amine groups in the Aminosilane agent could change the phase transition pH. Brushite particles revealed to have stronger interaction with pDNA mostly because of their higher positive surface charge. Both particles showed blood compatibility and negligible toxicity. Transfection experiment revealed the capability of both brushite and hydroxyapatite particles to transfect A549 and HEK293 cells. The new modified nanoparticles can be stored in a dried state and re-dispersed easily at the time of administration. Moreover, the transfection efficiency is higher in comparison with conventional calcium phosphate. This study showed the impact of presence and type of the modifying agent on the crystal structure and the amount of surface functionalization of nanoparticles, which in consequence influenced their interaction with cells.

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New Sustainable Ionic Polysaccharides Fibers Assist Calcium Phosphate Mineralization as Efficient Adsorbents

Fibers and Polymers ◽

10.1007/s12221-021-0757-8 ◽

2021 ◽

Author(s):

Ahmed Salama ◽

Ragab E. Abouzeid ◽

Nasser S. Awwad ◽

Hala A. Ibrahium

Keyword(s):

Calcium Phosphate ◽

Phosphate Mineralization

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Enhanced Osteogenesis of Dental Pulp Stem Cells In Vitro Induced by Chitosan–PEG-Incorporated Calcium Phosphate Cement

Polymers ◽

10.3390/polym13142252 ◽

2021 ◽

Vol 13 (14) ◽

pp. 2252

Author(s):

Jae Eun Kim ◽

Sangbae Park ◽

Woong-Sup Lee ◽

Jinsub Han ◽

Jae Woon Lim ◽

...

Keyword(s):

Stem Cells ◽

Calcium Phosphate ◽

Zeta Potential ◽

Mechanical Strength ◽

Calcium Phosphate Cement ◽

Dental Pulp ◽

Dental Pulp Stem Cells ◽

Ion Trapping ◽

Alizarin Red

The use of bone graft materials is required for the treatment of bone defects damaged beyond the critical defect; therefore, injectable calcium phosphate cement (CPC) is actively used after surgery. The application of various polymers to improve injectability, mechanical strength, and biological function of injection-type CPC is encouraged. We previously developed a chitosan–PEG conjugate (CS/PEG) by a sulfur (VI) fluoride exchange reaction, and the resulting chitosan derivative showed high solubility at a neutral pH. We have demonstrated the CPC incorporated with a poly (ethylene glycol) (PEG)-grafted chitosan (CS/PEG) and developed CS/PEG CPC. The characterization of CS/PEG CPC was conducted using Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD). The initial properties of CS/PEG CPCs, such as the pH, porosity, mechanical strength, zeta potential, and in vitro biocompatibility using the WST-1 assay, were also investigated. Moreover, osteocompatibility of CS/PEG CPCs was carried out via Alizarin Red S staining, immunocytochemistry, and Western blot analysis. CS/PEG CPC has enhanced mechanical strength compared to CPC, and the cohesion test also demonstrated in vivo stability. Furthermore, we determined whether CS/PEG CPC is a suitable candidate for promoting the osteogenic ability of Dental Pulp Stem Cells (DPSC). The elution of CS/PEG CPC entraps more calcium ion than CPC, as confirmed through the zeta potential test. Accordingly, the ion trapping effect of CS/PEG is considered to have played a role in promoting osteogenic differentiation of DPSCs. The results strongly suggested that CS/PEG could be used as suitable additives for improving osteogenic induction of bone substitute materials.

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Amorphous–Crystalline Calcium Phosphate Coating Promotes In Vitro Growth of Tumor-Derived Jurkat T Cells Activated by Anti-CD2/CD3/CD28 Antibodies

Materials ◽

10.3390/ma14133693 ◽

2021 ◽

Vol 14 (13) ◽

pp. 3693

Author(s):

Yurii P. Sharkeev ◽

Ekaterina G. Komarova ◽

Valentina V. Chebodaeva ◽

Mariya B. Sedelnikova ◽

Aleksandr M. Zakharenko ◽

...

Keyword(s):

T Cells ◽

Calcium Phosphate ◽

Biological Effects ◽

Electrical Potential ◽

Biological Properties ◽

Modern Trend ◽

Calcium Phosphate Coating ◽

Jurkat T Cells ◽

Micro Arc Oxidation

A modern trend in traumatology, orthopedics, and implantology is the development of materials and coatings with an amorphous–crystalline structure that exhibits excellent biocopatibility. The structure and physico–chemical and biological properties of calcium phosphate (CaP) coatings deposited on Ti plates using the micro-arc oxidation (MAO) method under different voltages (200, 250, and 300 V) were studied. Amorphous, nanocrystalline, and microcrystalline statesof CaHPO4 and β-Ca2P2O7were observed in the coatings using TEM and XRD. The increase in MAO voltage resulted in augmentation of the surface roughness Ra from 2.5 to 6.5 µm, mass from 10 to 25 mg, thickness from 50 to 105 µm, and Ca/P ratio from 0.3 to 0.6. The electrical potential (EP) of the CaP coatings changed from −456 to −535 mV, while the zeta potential (ZP) decreased from −53 to −40 mV following an increase in the values of the MAO voltage. Numerous correlations of physical and chemical indices of CaP coatings were estimated. A decrease in the ZP magnitudes of CaP coatings deposited at 200–250 V was strongly associated with elevated hTERT expression in tumor-derived Jurkat T cells preliminarily activated with anti-CD2/CD3/CD28 antibodies and then contacted in vitro with CaP-coated samples for 14 days. In turn, in vitro survival of CD4+ subsets was enhanced, with proinflammatory cytokine secretion of activated Jurkat T cells. Thus, the applied MAO voltage allowed the regulation of the physicochemical properties of amorphous–crystalline CaP-coatings on Ti substrates to a certain extent. This method may be used as a technological mechanism to trigger the behavior of cells through contact with micro-arc CaP coatings. The possible role of negative ZP and Ca2+ as effectors of the biological effects of amorphous–crystalline CaP coatings is discussed. Micro-arc CaP coatings should be carefully tested to determine their suitability for use in patients with chronic lymphoid malignancies.

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Calcium phosphate biomaterials for a local-delivery of bisphosphonate: Influence of chemical association on the in vitro activity

Bone ◽

10.1016/j.bone.2007.12.169 ◽

2008 ◽

Vol 42 ◽

pp. S89

Author(s):

Elise Verron ◽

Helene Roussiere ◽

Bruno Bujoli ◽

Pascal Janvier ◽

Jean Michel Bouler ◽

...

Keyword(s):

Calcium Phosphate ◽

Local Delivery ◽

Vitro Activity ◽

In Vitro Activity ◽

Chemical Association

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In Vitro Mineralization and Cell Adhesion on Surface Modified Poly (2 - hydroxy ethyl methacrylate-co-methyl methacrylate

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.309-311.493 ◽

2006 ◽

Vol 309-311 ◽

pp. 493-496 ◽

Cited By ~ 3

Author(s):

G.S. Sailaja ◽

T.V. Kumari ◽

Yoshiyuki Yokogawa ◽

H.K. Varma

Keyword(s):

Cell Adhesion ◽

Calcium Phosphate ◽

Methyl Methacrylate ◽

Radical Copolymerization ◽

Sem Analysis ◽

Free Radical Copolymerization ◽

In Vitro Mineralization ◽

Atr Spectroscopy ◽

Surface Modified

Poly(2-hydroxyethyl methacrylate-co- methyl methacrylate) HM, was synthesized by free radical copolymerization, cross-linked with ethylene glycol dimethacrylate and phosphorylated. The phosphate coupling was ensured by ATR spectroscopy. The in vitro mineralization ability of the phosphorylated HM (designated as PHM) was investigated by studying the nucleation and growth of calcium phosphate on its surface by immersing in simulated body fluid (SBF) solution. The coating morphology was studied by SEM and the Ca/P ratio of the coating by EDX analysis. The cell adhesion behaviour of PHM was studied by seeding Human osteosarcoma (HOS) cells for one week followed by SEM analysis along with HM as control. It was observed that HOS cells exhibited biomineralization of calcium phosphate on the surface of HM as well as on PHM with a significantly higher amount on the surface of PHM as observed by von kossa staining method. The results show that PHM is capable of in vitro mineralization under simulated physiological condition, promotes cell adhesion by providing an excellent cell friendly surface and it exhibits biomineralization of calcium phosphate in presence of HOS cells.

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