Sharif Digital Repository

Nanotechnology has emerged as a key technology which has opened new vistas to find effective therapies for cancer. Nanomaterials are particularly promising candidates for early diagnosis of cancer cells. Several classes of nanomaterials, including dendritic and supramolecular polymers, carbon nanotubes, graphene and metal nanoparticles, have shown tremendous ability to recognize and destroy cancer cells in vivo. In this book, some of these novel systems and their potential applications in cancer therapy are reviewed  

A series of ZIF-8/OND hybrid nanostructures with different percentages of oxidized nanodiamond (OND) was prepared. Then, the adsorptive removal performance of pristine ZIF-8 and its nanohybrids with OND towards methylene blue (MB) was investigated. The fabricated adsorbents were characterized via thermogravimetric analysis, X-ray diffraction, Fourier transform infrared spectroscopy, nitrogen adsorption/desorption, field emission scanning electron microscopy and zeta potential measurements. The maximal adsorption capacity of ZIF-8 (242 mg/g) was found to grow steadily with the increment in OND content and reached an approximate plateau at 343 mg/g for the nanohybrid containing 5 wt% OND, i.e.... 

The early diagnosis together with an efficient therapy of cancer is essential to treat cancer patients and to enhance their quality of life. The use of nanostructures, as a newer technology, has demonstrated proven benefits as efficient cancer theranostic agents in numerous recent studies. Having a tunable surface plasmon resonance, gold nanostructures have been the subject of many recent studies as excellent imaging and photothermal therapy agents. However, the potential cytotoxicity and weak stability of gold nanostructures necessitate further modifications using biocompatible materials for biological applications. Based on the composition of the final structure, these gold-based hybrid... 

Hybrid nanostructures combining semiconductor quantum dots and graphene are attracting increasing attention because of their optoelectronic properties promising for photovoltaic applications. We present a hot-injection synthesis of a colloidal nanostructure which we define as quasi core/shell PbS/graphene quantum dots due to the incomplete passivation of PbS surfaces with an ultrathin layer of graphene. Simulation by density functional theory of a prototypical model of a nonstoichiometric Pb-rich core (400 atoms) coated by graphene (20 atoms for each graphene sheet) indicates the possibility of surface passivation of (111) planes of PbS with graphene resulting in a decrease in trap states... 

In this study, a hybrid of silica nanosphere/multiwall carbon nanotube (MWCNT) has been synthesized by wet chemical method at room temperature. The effect of MWCNTs, silica nanospheres and hybrid nanostructures (80% silica nanosphere/20% MWCNT and 50% silica nanosphere/50% MWCNT) on the thermal conductivity of distilled water has been investigated. SDBS was used as the dispersant to stabilize nanomaterials in the aqueous suspension and its concentration was 1.5 times of the concentration of nanomaterials. As results show, by increasing the concentration of nanomaterials, effective thermal conductivity of nanofluids increased. The most and the least enhancement in the effective thermal... 

Molecular self-assembly of cadmium selenide quantum dots-end-capped polyrotaxane hybrid nanostructures (PRCdSe QDs) was led to a new type of core-shell hybrid nanomaterials consisting of cadmium selenide quantum dot (CdSe QDs) core and polyrotaxane shell (PR@QDs). Structure of PR@QDs was characterized using various techniques. It has been observed that the size of PR@QDs was between 20-25 nm in which diameter of core and thickness of shell were between 15-20 and 2-3 nm, respectively. Short-term in vitro cytotoxicity tests, using MTT (3-(4,5- dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay, were conducted on mouse tissue connective fibroblast adhesive cell line (L929) in order to... 

In this work, the addition of a novel polyaniline (PANI)/silica (SiO2) nanostructure (PSn) in chitosan/polyvinyl alcohol nanofibers (CP) was evaluated to enhance the dye removal capacity of CP. Fourier transform infrared spectroscopy (FTIR), field-emission scanning electron microscopy (FE-SEM), and energy-dispersive X-ray spectroscopy (EDS) results confirmed the chemical grafting of SiO2 on PANI nanoparticles. Brunauer-Emmett-Teller (BET) results showed a specific surface area of 61 m2 g−1 for the PSn filled CP nanofiber (CP-PSn). FE-SEM and EDS-elemental mapping results showed the uniform dispersibility of PSn in CP nanofibers. After the addition of PSn into CP, the adsorption capacity of... 

In this study, nano-sized diamond particles (ND) were functionalized in two consecutive stages. First, dry thermal oxidation was employed to obtain carboxylated ND. In the next step, carboxylated ND was properly surface modified through wet chemistry to acquire aminated-ND (ND-NH2). Then, polyaniline (PANI) was synthesized in the presence of aminated-ND particles at a broad concentration from 1 wt% to 70 wt% to obtain PANI/ND hybrid nanostructures. The chemical structure, morphology, and thermal stability of nanoparticles were comprehensively characterized by different techniques such as FT-IR, UV–visible, TGA, XRD, FESEM, and TEM. It was observed that the morphology of PANI/ND... 

Hybrid nanostructures and nanoarchitectures possess unique physicochemical properties such as high activity/functionality, enhanced physicochemical stability, and improved biocompatibility, which renders them suitable for various biomedical, pharmaceutical, environmental, and catalytic applications. In this context, core–shell nanophotocatalysts have shown superior activity compared to their counterparts, namely, their individual pristine semiconductors and composite materials components. Thus, the development of various innovative core–shell nanostructures as photocatalysts is of practical relevance in view of their unique properties with salient advantageous features applicable to, among... 

Polyrotaxanes consisting of cyclodextrin rings, polyethylene glycol axes and quantum dot (QD) stoppers were synthesized and characterized. The molecular self-assembly of polyrotaxanes led to spindlelike nano-objects whose shape, size and position were dominated by QD stoppers. Due to their well-defined molecular self-assemblies, carbohydrate backbone, high functionality and several types of functional groups together with the high luminescence yield, synthesized hybrid nanostructures were recognized as promising candidates for biomedical applications. The potential applications of the molecular self-assemblies as drug-delivery systems was investigated by conjugation of doxorubicin (DOX) to...