The crystallite size of commercial ZnO nanocrystals was tuned from 22.5 to 13.8 nm by ball-milling technique. X-ray diffraction patterns of mechanically milled ZnO nanocrystals reveal that milled samples possess the wurtzite-type hexagonal structure of ZnO. Increasing milling time results in the decrease of crystallite size and reduction of lattice parameters due to a slight increase of internal compressive strain and dislocation density. Scanning electron microscope images demonstrate the appearance of large agglomerated particles with ambiguous edges due to large aggregation tendency with slight variation in the particle size at milling time 8 h. Analysis of the optical absorption spectra at different milling time indicates the blue shift of exciton absorption peak and optical gap photoluminescence spectra reveal that mechanical milling of ZnO NCs leads to quenching of emission intensity due to the creation of nonradiative centers via increasing thermal strain and mechanical deformation produced during the milling process.

The crystallite size of commercial ZnO nanocrystals was tuned from 22.5 to 13.8 nm by ball-milling technique. X-ray diffraction patterns of mechanically milled ZnO nanocrystals reveal that milled samples possess the wurtzite-type hexagonal structure of ZnO. Increasing milling time results in the decrease of crystallite size and reduction of lattice parameters due to a slight increase of internal compressive strain and dislocation density. Scanning electron microscope images demonstrate the appearance of large agglomerated particles with ambiguous edges due to large aggregation tendency with slight variation in the particle size at milling time 8 h. Analysis of the optical absorption spectra at different milling time indicates the blue shift of exciton absorption peak and optical gap photoluminescence spectra reveal that mechanical milling of ZnO NCs leads to quenching of emission intensity due to the creation of nonradiative centers via increasing thermal strain and mechanical deformation produced during the milling process.

The crystallite size of commercial ZnO nanocrystals was tuned from 22.5 to 13.8 nm by ball-milling technique. X-ray diffraction patterns of mechanically milled ZnO nanocrystals reveal that milled samples possess the wurtzite-type hexagonal structure of ZnO. Increasing milling time results in the decrease of crystallite size and reduction of lattice parameters due to a slight increase of internal compressive strain and dislocation density. Scanning electron microscope images demonstrate the appearance of large agglomerated particles with ambiguous edges due to large aggregation tendency with slight variation in the particle size at milling time 8 h. Analysis of the optical absorption spectra at different milling time indicates the blue shift of exciton absorption peak and optical gap photoluminescence spectra reveal that mechanical milling of ZnO NCs leads to quenching of emission intensity due to the creation of nonradiative centers via increasing thermal strain and mechanical deformation produced during the milling process.

In the present study, we investigate the excitation wavelength dependent photoluminescence (PL) behavior in Zn0.45Cd0.55S nanoparticles. The deconvoluted PL emission bands for nanopowders and nanocolloids reveal noticeable spectral blue shift with decreasing lex accompanied by intensity enhancement. This unusual behavioris explained in terms of selective particle size distribution in nanostructures, advancing of fast ionization process at short lex; and solvation process in polar solvent. In addition, we attributed the UV-induced PL intensity enhancement and blue shift of the optical gap to the reduction in particle size by photo-corrosion process associated with the improvement in the quantum size effect; surface modification due to cross-linkage improvement of capping molecules at NPs surface; the creation of new radiative centers and the formation of photo-passivation layers from ZnSO4 and CdSO4, and photo-enhanced oxygen adsorption on Zn0.45Cd0.55S nanoparticles surface.

In the present study, we investigate the excitation wavelength dependent photoluminescence (PL) behavior in Zn0.45Cd0.55S nanoparticles. The deconvoluted PL emission bands for nanopowders and nanocolloids reveal noticeable spectral blue shift with decreasing lex accompanied by intensity enhancement. This unusual behavioris explained in terms of selective particle size distribution in nanostructures, advancing of fast ionization process at short lex; and solvation process in polar solvent. In addition, we attributed the UV-induced PL intensity enhancement and blue shift of the optical gap to the reduction in particle size by photo-corrosion process associated with the improvement in the quantum size effect; surface modification due to cross-linkage improvement of capping molecules at NPs surface; the creation of new radiative centers and the formation of photo-passivation layers from ZnSO4 and CdSO4, and photo-enhanced oxygen adsorption on Zn0.45Cd0.55S nanoparticles surface.

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A novel series of (Z)-3,5-disubstituted thiazolidine-2,4-diones 4-16 has been designed and synthesized. Preliminary screening of these compounds for their anti-breast cancer activity revealed that compounds 5, 7, and 9 possess the highest anti-cancer activities. The anti-tumor effects of compounds 5, 7, and 9 were evaluated against human breast cancer cell lines (MCF-7 and MDA-MB-231) and human breast cancer cells. They were also evaluated against normal non-cancerous breast cells, isolated from the same patients, to conclude about their use in a potential targeted therapy. Using MTT uptake method, these three compounds 5, 7, and 9 blunt the proliferation of these cancer cells in a dose-dependent manner with an IC50 of 1.27, 1.50 and 1.31 µM respectively. Interestingly, using flow cytometry analysis these three compounds significantly mediated apoptosis of human breast cancer cells without affecting the survival of normal non-cancerous breast cells that were isolated from the same patients. Mechanistically, these compounds blunt the proliferation of MCF-7 breast cancer cells by robustly decreasing the phosphorylation of AKT, mTOR and the expression of VEGF and HIF-1α. Most importantly, compounds 5, 7, and 9 without affecting the phosphorylation and expression of these crucial cellular factors in normal non-cancerous breast cells that were isolated from the same patients. Additionally, using Western blot analysis the three compounds significantly (P 0.05) decreased the expression of the anti-apoptotic Bcl-2 members (Bcl-2, Bcl-XL and Mcl-1) and increased the expression of the pro-apoptotic Bcl-2 members (Bak, Bax and Bim) in MCF-7, MDA-MB-231 and human breast cancer cells making these breast cancer cells susceptible for apoptosis induction. Taken together, these data provide great evidences for the inhibitory activity of these compounds against breast cancer cells without affecting the normal breast cells.

A novel series of (Z)-3,5-disubstituted thiazolidine-2,4-diones 4-16 has been designed and synthesized. Preliminary screening of these compounds for their anti-breast cancer activity revealed that compounds 5, 7, and 9 possess the highest anti-cancer activities. The anti-tumor effects of compounds 5, 7, and 9 were evaluated against human breast cancer cell lines (MCF-7 and MDA-MB-231) and human breast cancer cells. They were also evaluated against normal non-cancerous breast cells, isolated from the same patients, to conclude about their use in a potential targeted therapy. Using MTT uptake method, these three compounds 5, 7, and 9 blunt the proliferation of these cancer cells in a dose-dependent manner with an IC50 of 1.27, 1.50 and 1.31 µM respectively. Interestingly, using flow cytometry analysis these three compounds significantly mediated apoptosis of human breast cancer cells without affecting the survival of normal non-cancerous breast cells that were isolated from the same patients. Mechanistically, these compounds blunt the proliferation of MCF-7 breast cancer cells by robustly decreasing the phosphorylation of AKT, mTOR and the expression of VEGF and HIF-1α. Most importantly, compounds 5, 7, and 9 without affecting the phosphorylation and expression of these crucial cellular factors in normal non-cancerous breast cells that were isolated from the same patients. Additionally, using Western blot analysis the three compounds significantly (P 0.05) decreased the expression of the anti-apoptotic Bcl-2 members (Bcl-2, Bcl-XL and Mcl-1) and increased the expression of the pro-apoptotic Bcl-2 members (Bak, Bax and Bim) in MCF-7, MDA-MB-231 and human breast cancer cells making these breast cancer cells susceptible for apoptosis induction. Taken together, these data provide great evidences for the inhibitory activity of these compounds against breast cancer cells without affecting the normal breast cells.