Nanohydroxyapatite-Mediated Imatinib Delivery for Specific Anticancer Applications

In the present study, a nanoapatite-mediated delivery system for imatinib has been proposed. Nanohydroxyapatite (nHAp) was obtained by co-precipitation method, and its physicochemical properties in combination with imatinib (IM) were studied by means of XRPD (X-ray Powder Diffraction), SEM-EDS (Scanning Electron Microscopy-Energy Dispersive X-ray Spectroscopy), FT-IR (Fourier-Transform Infrared Spectroscopy), absorption spectroscopy as well as DLS (Dynamic Light Scattering) techniques. The obtained hydroxyapatite was defined as nanosized rod-shaped particles with high crystallinity. The amorphous imatinib was obtained by conversion of its crystalline form. The beneficial effects of amorphous pharmaceutical agents have been manifested in the higher dissolution rate in body fluids improving their bioavailability. Imatinib-to-hydroxyapatite interactions on the surface were confirmed by SEM images as well as absorption and FT-IR spectroscopy. The cytotoxicity of the system was tested on NI-1, L929, and D17 cell lines. The effectiveness of imatinib was not affected by nHAp modification. The calculated IC50 values for drug-modified nHAp were similar to those for the drug itself. However, higher cytotoxicity was observed at higher concentrations of imatinib, in comparison with the drug alone

Effects of crystalline growth on structural and luminescence properties of Ca (10-3x) Eu 2x (PO 4 ) 6 F 2 nanoparticles fabricated by using microwave driven hydrothermal process

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Correction: Effects of crystalline growth on structural and luminescence properties of Ca (10−3x) Eu 2x (PO 4 ) 6 F 2 nanoparticles fabricated by using a microwave driven hydrothermal process

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Synergistic Effect of Toceranib and Nanohydroxyapatite as a Drug Delivery Platform—Physicochemical Properties and In Vitro Studies on Mastocytoma Cells

A new combination of Toceranib (Toc; 5-[(5Z)-(5-Fluoro-2-oxo-1,2-dihydro-3H-indol-3-ylidene)methyl]-2,4-dimethyl-N-[2-(pyrrolidin-1-yl)ethyl]-1H-pyrrole-3-carboxamide) with nanohydroxyapatite (nHAp) was proposed as an antineoplastic drug delivery system. Its physicochemical properties were determined as crystallinity, grain size, morphology, zeta potential and hydrodynamic diameter as well as Toceranib release. The crystalline nanorods of nHAp were synthesised by the co-precipitation method, while the amorphous Toceranib was obtained by its conversion from the crystalline form during nHAp–Toc preparation. The surface interaction between both compounds was confirmed using Fourier-transform infrared spectroscopy (FT-IR), ultraviolet-visible spectroscopy (UV–Vis) and scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDS). The nHAp–Toc showed a slower and prolonged release of Toceranib. The release behaviour was affected by hydrodynamic size, surface interaction and the medium used (pH). The effectiveness of the proposed platform was tested by comparing the cytotoxicity of the drug combined with nHAp against the drug itself. The compounds were tested on NI-1 mastocytoma cells using the Alamar blue colorimetric technique. The obtained results suggest that the proposed platform shows high efficiency (the calculated IC50 is 4.29 nM), while maintaining the specificity of the drug alone. Performed analyses confirmed that nanohydroxyapatite is a prospective drug carrier and, when Toceranib-loaded, may be an idea worth developing with further research into therapeutic application in the treatment of canine mast cell tumour

Effect of lithium substitution on the charge compensation, structural and luminescence properties of nanocrystalline Ca10(PO4)6F2 activated with Eu3+ ions

International audienceEu3+ and Li+ ion co-doped fluorapatite (Ca10(PO4)6F2) nanocrystals were fabricated using a microwave stimulated hydrothermal technique followed by heat treatment at 500 °C. The concentration of Eu3+ ions was set to be 1 mol% and that of the Li+ ions was in the range of 0.5–5 mol% to investigate the site occupancy preference and charge compensation co-doping. The structural and morphological properties of the obtained samples were determined by using XRD (X-ray powder diffraction) and TEM (transmission electron microscopy) techniques as well as IR (infrared) and micro-Raman spectroscopy. The particle size was verified and calculated by the Rietveld method being in the range of 70–95 nm. The luminescence properties (the emission, excitation spectra and emission kinetics) of the Eu3+ ion-doped fluorapatite depending on the co-dopant (Li+ ions) were recorded. Significantly, fluorescence quenching by OH− groups was eliminated by F- ions and the luminescence intensity was enhanced by co-doping with Li+ ions. The simplified Judd–Ofelt (J–O) theory has been performed to explain a detailed analysis of the luminescence spectra

Nanohydroxyapatite as a Biomaterial for Peripheral Nerve Regeneration after Mechanical Damage—In Vitro Study

Hydroxyapatite has been used in medicine for many years as a biomaterial or a cover for other biomaterials in orthopedics and dentistry. This study characterized the physicochemical properties (structure, particle size and morphology, surface properties) of Li+- and Li+/Eu3+-doped nanohydroxyapatite obtained using the wet chemistry method. The potential regenerative properties against neurite damage in cultures of neuron-like cells (SH-SY5Y and PC12 after differentiation) were also studied. The effect of nanohydroxyapatite (nHAp) on the induction of repair processes in cell cultures was assessed in tests of metabolic activity, the level of free oxygen radicals and nitric oxide, and the average length of neurites. The study showed that nanohydroxyapatite influences the increase in mitochondrial activity, which is correlated with the increase in the length of neurites. It has been shown that the doping of nanohydroxyapatite with Eu3+ ions enhances the antioxidant properties of the tested nanohydroxyapatite. These basic studies indicate its potential application in the treatment of neurite damage. These studies should be continued in primary neuronal cultures and then with in vivo models

Nanocrystalline Hydroxyapatite Loaded with Resveratrol in Colloidal Suspension Improves Viability, Metabolic Activity and Mitochondrial Potential in Human Adipose-Derived Mesenchymal Stromal Stem Cells (hASCs)

In response to the demand for new multifunctional materials characterized by high biocompatibility, hydrogel (HG) nanocomposites as a platform for bioactive compound delivery have been developed and fabricated. A specific crosslinking/copolymerization chemistry was used to construct hydrogels with a controlled network organization. The hydrogels were prepared using 3,6-anhydro-α-l-galacto-β-d-galactan (galactose hydrogel) together with resveratrol (trans-3,5,4′-trihydroxystilbene) and calcium hydroxyapatite nanoparticles. The resveratrol was introduced in three different concentrations of 0.1, 0.5, and 1 mM. Nanosized calcium hydroxyapatite was synthesized by a microwave-assisted hydrothermal technique, annealed at 500 °C for 3 h, and introduced at a concentration 10% (m/v). The morphology and structural properties of Ca10(PO4)6(OH)2 and its composite were determined by using XRPD (X-ray powder diffraction) techniques, as well as the absorption and IR (infrared) spectroscopy. The average nanoparticle size was 35 nm. The water affinity, morphology, organic compound release profile, and cytocompatibility of the obtained materials were studied in detail. The designed hydrogels were shown to be materials of biological relevance and of great pharmacological potential as carriers for bioactive compound delivery. Their cytocompatibility was tested using a model of human multipotent stromal cells isolated from adipose tissue (hASCs). The biomaterials increased the proliferative activity and viability of hASCs, as well as reduced markers of oxidative stress. In light of the obtained results, it has been thought that the designed materials meet the requirements of the tissue engineering triad, and may find application in regenerative medicine, especially for personalized therapies

<p>Fe₃O₄ Magnetic Nanoparticles Under Static Magnetic Field Improve Osteogenesis via RUNX-2 and Inhibit Osteoclastogenesis by the Induction of Apoptosis</p>

International audiencePurpose: The presented study aimed to investigate the effects of Fe 3O 4 nanoparticles and static magnetic field on osteoblast and osteoclasts’ metabolic activity.Methods: Magnetic nanoparticles were prepared by a wet chemical co-precipitation process and analyzed using X-ray powder diffraction, high-resolution transmission electron microscope (HRTEM), dynamic light scattering (DLS), laser Doppler velocimetry, Raman and the Mössbauer spectroscopy. In vitro experiments were performed using MC3T3, 4B12 and RAW 264.7 cell lines. Cells were cultured in the presence of nanoparticles and with or without exposure to the magnetic field. Proteins were investigated with Western blotting and immunofluorescence and Western blot. Gene expression was analyzed with a quantitative real-time polymerase chain reaction.Results: Obtained particles were in the nano-range (average size around 50 nm) and had a spherical-like morphology. The typical hydrodynamic size was in the range 178– 202 nm and Zeta potential equaled – 9.51 mV. Mössbauer spectrum corresponds to the Fe+3 ions in tetrahedral (A) and Fe+3 and Fe+2 ions in octahedral (B) sites of Fe 3O 4. In vitro study revealed cytocompatibility and anti-inflammatory effects of fabricated nanoparticles. Furthermore, it was shown that nanoparticles combined with magnetic field exposure enhance osteogenic differentiation of MC3T3 cells by upregulation of RUNX-2 activity. Under the same experimental condition, nanoparticles and magnetic field decreased osteoclastogenesis of 4B12 by the induction of apoptosis through the mitochondrial-dependent pathway.Conclusion: Fe 3O 4 nanoparticles together with magnetic field can be applied for the fabrication of novel biomaterials for the treatment of bone disorders related to bone loss in which a balance between bone-forming and resorbing cells is disturb

Preparation of up-converting nano-biphasic calcium phosphate

International audienceThe nano-biphasic calcium phosphate co-doped with 1 mol% Er3+ and 5 mol% Yb3+ ions was prepared using Pechini's technique. The preparation of the biphasic calcium phosphate showed the removal of fluorine ions from the matrix. The structural properties and morphology of the particles were studied by means of XRD (X-ray powder diffraction), TEM (Transmission Electron Microscopy), and SEM (Scanning Electron Microscopy) techniques. The spectroscopic properties of Ca10(PO4)6F2/Ca3(PO4)2:Er3+,Yb3+ nano-biphasic calcium phosphate were investigated in detail using emission spectra, power dependence and emission kinetics. This material demonstrated intense green up-conversion depending on laser power. Additionally, the luminescence lifetimes for Er3+ ions were calculated from the measured decays. Power dependence of the green and red emissions was found to result from a temperature increase of nano-biphasic calcium phosphate that opens potential applications in theranostics

Aminopropyltriethoxysilane (APTES)-Modified Nanohydroxyapatite (nHAp) Incorporated with Iron Oxide (IO) Nanoparticles Promotes Early Osteogenesis, Reduces Inflammation and Inhibits Osteoclast Activity

Due to its increased prevalence, osteoporosis (OP) represents a great challenge to health care systems and brings an economic burden. To overcome these issues, treatment plans that suit the need of patients should be developed. One of the approaches focuses on the fabrication of personalized biomaterials, which can restore the balance and homeostasis of disease-affected bone. In the presented study, we fabricated nanometer crystalline hydroxyapatite (nHAp) and iron oxide (IO) nanoparticles stabilized with APTES and investigated whether they can modulate bone cell metabolism and be useful in the fabrication of personalized materials for OP patients. Using a wide range of molecular techniques, we have shown that obtained nHAp@APTES promotes viability and RUNX-2 expression in osteoblasts, as well as reducing activity of critical proinflammatory cytokines while inhibiting osteoclast activity. Materials with APTES modified with nHAp incorporated with IO nanoparticles can be applied to support the healing of osteoporotic bone fractures as they enhance metabolic activity of osteoblasts and diminish osteoclasts&rsquo; metabolism and inflammation