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This work aimed to evaluate new materials to be carried out as scaffolds using breast cancer cells MCF-7. These new nanocomposites were prepared through blending of gelatin with poly (DL-lactide-co-glycolide) (PLG) in presence of titanium nanowires (TiO2 ) and cartilage powder (CP). The prepared nanomaterials were characterized using Fourier transform infrared spectroscopy, thermogravimetric analysis, scanning electron microscope, and transmitting electron microscope. Moreover, the MCF-7 cells were in vitro tested with apoptosis/necrosis assay, micronucleus test, and DNA fragmentation and MMT assay. TiO2 nanowires and CP particles have diameters around 28-128 and 17-20 nm, respectively. These were coated with gelatin matrix. Seeding of MCF-7 cells with the prepared nanomaterials revealed high cell attachment to their surfaces and they were viable after 72 h. It has been shown that the prepared nanocomposites did not induce necrotic effects on MCF-7 cells; however, they induced a significant DNA fragmentation in comparison with the nontreated control cells., (Copyright © 2012 Wiley Periodicals, Inc.)

The combination of gelatin (Gel) with a bioactive component hydroxyapatite (HA) and cartilage powder (CP) to form biocomposites takes advantage of the osteoconductivity and osteoinductivity properties. The studies on bionanocomposites containing HA, CP fillers and Gel are still being conducted. In this present study, the bioactive fillers were loaded onto poly(hydroxylethylmethacrylate) and poly(hydroxylethylmethacrylate-co-methyl methacrylate) grafted gelatin copolymers to produce novel bionanocomposites having osteoconductive and osteoinductive properties. The resulting bionanocomposites were assessed by ATR-IR and SEM-EDX techniques to prove the interaction between different matrices. In vitro behavior of these bionanocomposites was performed in SBF for 21 days at pH 7.4 to verify formation of the apatite layer on the surfaces and its enhancement. The results confirmed the formation of thick plentiful aggregated (hexagonal or spherical) nanoparticles with a bright color (apatite layer) containing carbonate ions onto the surface of composites especially these containing CP and P(HEMA-co-MMA) having bone cement formation in their structure. These novel bionanocomposites have unique bioactivity that can be applied in bone implants as scaffolds and tissue engineering in future., (Copyright 2010 Elsevier B.V. All rights reserved.)

The limitation in bone tissue engineering is the lack of available natural or synthetic biomaterials to replace bone tissue under need. Carbon nanotubes have great potential as bone tissue scaffolds because of their remarkable mechanical and electrical properties combined with high aspect ratio. In this work, we demonstrated for the first time a novel approach based on the sol-gel technique for functionalization of multi-walled carbon nanotubes (MWCNTs) with two amino acids: L-arginine, L(+) Arg and L-aspargine, L(+) Asp. We have examined the effect of both functionalities on physicochemical properties of MWCNTs, cytotoxicity in osteosarcoma MG63 and normal fibroblastic BJ cells and the ability to induce nucleation and growth of hydroxyapatite (HA) crystals in vitro under physiological concentrations of Ca2+ and PO4+ (SBF). The scaffolds were characterized using Fourier transform infrared spectroscopy (FTIR-ATR), dynamic light scattering technique (DLS), X-ray diffraction (XRD), thermogravimetric analysis (TGA) and scanning electron microscopy (SEM). The results showed that both functionalized MWCNTs have a particle size of 269 and 411 nm, a zeta potential of -12.8 and -8.8 mV, respectively, high colloidal stability, enhanced biocompatibility, and enhanced formation of an apatite layer on the scaffolds surface in comparison to ox-MWCNTs. Altogether, the results confirmed the important role of the amino acids L(+) Arg and L(+) Asp in ox-MWCNTs-based composites for bone tissue engineering applications. [ABSTRACT FROM AUTHOR]

Chlorinated poly(vinyl chloride) (CPVC)/calcium carbonate nanocomposites were successfully prepared by the incorporation of calcium carbonate (CaCO3) nanoparticles into the CPVC matrix. The compatibility between the two phases was obtained by surface modification of the CaCO3 nanoparticles with stearic acid, leading to improved material performance. The effects of the addition of different amounts of CaCO3 nanoparticles to the CPVC on the thermal, mechanical, and morphological characteristics of the CPVC/CaCO3 nanocomposites were investigated. The thermal stability of the CPVC/CaCO3 nanocomposites was evaluated by thermogravimetric analysis and differential scanning calorimetry. In addition, the surface texture of the CPVC and the dispersion of the CaCO3 were evaluated using scanning electron microscopy. Important enhancements in the thermal and mechanical properties of the modified CPVC/CaCO3 nanocomposites were obtained by incorporating different amounts (2.00%, 3.75%, and 5.75%) of surfacemodified CaCO3 nanoparticles within the CPVC polymer matrix. The results reveal that 3.75% of CaCO3 was the optimum amount, where the CPVC/CaCO3 nanocomposite shows the highest impact strength, the highest tensile strength, the highest thermal stability, and the lowest elongation percentage: Replacement of the commercial impact modifier used in industry with the prepared surface-modified CaCO3 nanoparticles for the development of CPVC was successfully achieved. [ABSTRACT FROM AUTHOR]

Enoxaparin-immobilized gelatin/poly(ε-caprolactone) (PCL) or Eudragit® RS230D nanogels in the presence of tetraethyl orthosilicate (TEOS) as polycondensation reagent were designed and characterized for their sustained drug delivery ability. Enoxaparin (anti-Xa 1000 UI/mL) was used as a model drug at different concentrations (300, 500, and 1000 UI/mL). The resulting nanogels were prepared using sol-gel technique and analyzed using several analytical tools such as: thermal analysis (DSC and TGA), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning and transmitting electron microscopes (SEM and TEM). In addition to particle size, zeta potential and in vitro release profiles were also investigated. A burst effect was observed, afterwards, the release rate became steady. The immobilization of enoxaparin into the gel network led to the formation of stable nanogels with ionic functional groups, which enable the efficient loading and sustainable release. The preliminary results showed that enoxaparin-immobilized PCL-based nanogels in this study can be utilized in the design of a sustained delivery system. [ABSTRACT FROM AUTHOR]