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Cancer cells become resistant over the period to chemotherapeutic drugs and pose a challenging impediment for oncologists in providing effective treatment. Nanomedicine allows to overcome chemoresistance and is the focus of our investigation. Silica nanostructures have been highlighted as an interesting drug delivery platform in vitro and in vivo applications. Here we show the validity of nanomedicine approach for targeted chemotherapeutic cargo delivery to overcome chemoresistance in cancer cells both in vitro and in vivo. For demonstrating the concept, we functionalised ∼100 nm long porous silica nanoparticles (∼20 nm diameter ordered pore structure) by conjugating anticancer drug, cytochrome c enzyme and dual-function anticancer aptamer AS1411 in single supra-assembled nanocargos. The supra-assembly on the porous silica nanostructure allows for a high loading of catalytic enzyme cytochrome c, anticancer drug and aptamer. The silica supra-assembly is characterized by transmission electron microscopy (TEM) and Brunauer-Emmett-Teller (BET) surface area analysis. Conjugation of cargoes has been monitored at each step by UV-vis and Fluorescence spectroscopy. Finally, the constructed supra-assembled nanocarrier tested on chemoresistance colon cancer (HCT116) cells. A pH-responsive, intracellular theranostic cargo delivery has been achieved and the triple action of the nanocargo made an efficient killing of drug resistance colon cancer cells in vitro (∼ 92% cell death) through triplex therapy effects by supressing the P-glycoprotein (P-gp) level. Furthermore, in vivo animal toxicity studies demonstrated, the supra-assembled nanocargos have encouraging safety index to be used in cancer therapy and drug delivery applications., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Surface of La(0.7)Sr(0.3)MnO3 (LSMO) magnetic nanoparticles (MNPs) is functionalized with polymer (dextran) and their colloidal stability in various mediums is carried out. The influence of the surface functionalization of LSMO MNPs on their colloidal stability in physiological media is studied and correlated with their hyperthermia properties. Many studies have concerned the colloidal stability of MNPs coated with polymer, but their long-term stability when such complexes are exposed to physiological media is still not well understood. After zeta potential study, it is found that the dextran coating on MNPs improves the colloidal stability in water as well as in physiological media like PBS. The specific absorption rates (SAR) of these MNPs are found to be in 50-85 W/g in different concentrations of glucose and NaCl; and there values are suitable for hyperthermia treatment of cancer cells under AC magnetic field. After incorporation of MNPs up to 0.2-1mg/mL in 2 × 10(5)cells/mL (L929), the apoptosis and necrosis studies are carried out by acridine orange and ethidium bromide (AO and EB) staining and followed by visualization of microstructures under a fluorescence microscope. It is found that there are no morphological changes (i.e. no signs of cell rounding, bubble formation on the membrane and nuclear fragmentation) suggesting biocompatibility of dextran coated LSMO nanoparticles up to these concentrations., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Now-a-days surface functionalized La(0.7)Sr(0.3)MnO(3) (LSMO) nanoparticles by different biocompatible polymers are attracted considerable interest in various biomedical applications in general and magnetic fluid hyperthermia treatment of cancer in particular. In this paper La(0.7)Sr(0.3)MnO(3) nanoparticles are synthesized and functionalized with polymer (dextran, with mean particle size ~25 nm). Magnetic measurements of both coated and uncoated particles reveal the superparamagnetic nature at room temperature. The resulting coated particles form a stable suspension in an aqueous environment at physiological pH and possess a narrow hydrodynamic size distribution. In vitro cytotoxicity of the MNPs has been assessed under Trypan blue dye exclusion and MTT assay on HeLa and L929 cell lines. The results demonstrate that dextran functionalized nanoparticles have no significant effect on cell viability within the tested concentrations (0.2-1 mg/mL) as compared to bare LSMO. Magnetic fluid hyperthermia studies have been done in detail; the influence of an applied alternating current (AC) magnetic field on heat generation is presented in brief. Dextran functionalized LSMO has the higher Specific absorption rate (SAR) value than the bare LSMO. After functionalization with dextran the SAR values of LSMO nanoparticles increased from 25 to 51 W/g. The study shows that the rise in temperatures by these nanoparticles could be safely controlled around Curie temperature (T(c))., (Copyright © 2012 Elsevier B.V. All rights reserved.)