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Presently, quite a lot of research that are being carried out to find a potential cure for cancer and many had made to clinical trial stage as well. In the present study, we focus on use of a novel graphene oxide functionalized chitosan nanoparticle targeting Saos-2 and MG-63 osteosarcoma cells. The graphene oxide chitosan nanoparticles were loaded with siRNA, studied for in vitro release with varying concentration & pH, and fitted to peppas model. MTT & ROS assay was used to evaluate biocompatibility of carrier and qPCR to study the inflammatory responses in particular checking gene expression of IL-6, TGF-ß, TNF-α in both RAW 264.7 and bone marrow derived macrophages. The results of study showed that release of siRNA were in a controlled fashion and effective at acidic pH that prevails on tumor site. The material was biocompatible and effective in case of Saos-2 osteosarcoma cells with a viability of 0.4±0.43 and 0.49±0.53 in case of MG-63 cells when treated with highest concentration of 100µl siRNA compared to untreated cells that were in range of 0.64±0.67 in Saos-2 and 0.61±0.63 in MG-63 cells. The results of expression of inflammatory cytokines IL-6, TGF-β & TNF-α showed negligible amount compared to control group serving the purpose of an effective carrier targeting tumor cells. Highlights  Graphene oxide functionalized chitosan nanoparticle loaded with siRNA targeting Saos-2 and MG-63 osteosarcoma cells exhibited a controlled release.  Effective release of siRNA on cancer cells and destruction of the same.  No inflammation observed when treated with RAW and Bone Marrow derived macrophages derived from mice models.

BackgroundThe application of polymeric materials in medical industry has grown drastically in the last two decades due to their various advantages compared to existing materials. The present research work emphases on the sol-gel technique to formulate the polymethyl methyl acrylate/polystyrene/silica composite membrane.MethodsThe characteristic of the composite was investigated through modern state art of instrumentation.ResultsThe functional groups attached to the polymer was absorbed by FTIR. The FTIR spectrum confirm that the blend was mixed thoroughly and the formation of unite intimately between the polymers. The membranes were observed by SEM for its surface homogeneity which depends upon the composition of the two blending polymers. The captured SEM images showed the formation of microcracks on the surface, which was evidently controlled by varying the constituent polymer ratios. The prepared blend membranes with 2:1 ratio of PMMA/PS/Si displayed higher water uptake compared to other blended membranes. The composite membranes had good hydroxyl apatite growth in SBF solution. Furthermore, the in vitro cytotoxicity studies carried out by MTT method, using RAW macrophage cells showed that all the samples exhibited excellent cell viability.ConclusionThe inflammatory response of composite with equal concentration of PMMA-PS were performed and observed no inflammation in comparison with control and other tested concentrations.

The generation of fast electrochemical response with high sensitivity is a significant parameter for enzymatic biosensors. However, establishing nanocomposite based modified electrode with fast electron shuttling between enzymes and the electrode surface for determination of hydrogen peroxide (H 2 O 2 ) is highly challenging. Herein, the present work aims to develop second generation horseradish peroxidase (HRP) biosensors using Au nanochains dropcasted over electrochemically reduced graphene oxide-chitosan (ERGO-CHIT), a bio-nanocomposite film modified glassy carbon electrode (GCE) for reduction of H 2 O 2 is demonstrated. The experimental conditions including effect of pH, loading of enzyme on the electrode surface and concentration of redox mediator as electrolyte were optimized. As a result, the HRP/Au/ERGO-CHIT/GCE electrode shows a larger enhancement in cathodic current signal with sharp peak response for reduction of H 2 O 2 , which can be attributed to the presence of Au nanochains on the modified electrode which improves the electron transfer between heme (Fe 2+ /Fe 3+ ) center of enzymes on the electrode and the redox mediator in the electrolyte solution. The presence of HQ redox mediator in the electrolyte solution have provided stable peak response and offered more beneficiary in lowering the operating potential for the detection of H 2 O 2 (−0.1 V), thereby reducing the influence from interference species. From the amperometric measurements, the HRP/Au/ERGO-CHIT/GCE modified electrode revealed high sensitivity (368.01 μA mM −1 cm −2 ) and possesses wide linear range (0.01 to 6.31 mM) which is mainly due to the high surface area and conductivity offered by Au nanochains which are located between ERGO and HRP. The resultant HRP/Au/ ERGO-CHIT/GCE was found to possess good operational stability, high reproducibility, repeatability with low detection limits (4 μM), and thus it could be applicable for sensitive and rapid responsive detection of H 2 O 2 in biological, clinical and environmental samples.

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