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The growing resistance of bacteria to antibiotics has posed challenges in treating associated bacterial infections, while the development of multi-model antibacterial strategies could efficient sterilization to prevent drug resistance. High-entropy MXene has emerged as a promising candidate for antibacterial synergy with inherent photothermal and photodynamic properties. Herein, a high-entropy nanomaterial of MXene/CDs was synthesized to amplify oxidative stress under near-infrared laser irradiation. Well-exfoliated MXene nanosheets have proven to show an excellent photothermal effect for sterilization. The incorporation of CDs could provide photo-generated electrons for MXene nanosheets to generate ROS, meanwhile reducing the recombination of electron-hole pairs to further accelerate the generation of photo-generated electrons. The MXene/CDs material demonstrates outstanding synergistic photothermal and photodynamic effects, possesses excellent biocompatibility and successfully eliminates drug-resistant bacteria as well as inhibits biofilm formation. While attaining a remarkable killing efficiency of up to 99.99% against drug-resistant Escherichia coli and Staphylococcus aureus, it also demonstrates outstanding antibacterial effects against four additional bacterial strains. This work not only establishes a synthesis precedent for preparing high-entropy MXene materials with CDs but also provides a potential approach for addressing the issue of drug-resistant bacterial infections., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The biological applicability of nanomaterials has been limited due to cytotoxicity. Studies have described the effects of nanomaterials on different tissues and cell types, but their actions on immune cells are less elucidated. This study describes unprecedented in vitro and in vivo antioxidant activities of cadmium selenide magic-sized quantum dots (CdSe MSQDs) with implications on rheumatoid arthritis. While the generation of ROS induced by nanomaterials is linked to cytotoxicity, we found that CdSe MSQDs reduced ROS production by neutrophils and macrophages following opsonized-zymosan stimuli, and we did not find cytotoxic effects. Interestingly, inherent antioxidant properties of CdSe MSQDs were confirmed through DPPH, FRAP, and ORAC assays. Furthermore, CdSe MSQDs reduced ROS levels generated by infiltrating leukocytes into joints in experimental model of rheumatoid arthritis. Briefly, we describe a novel application of CdSe MSQDs in modulating the inflammatory response in experimental rheumatoid arthritis through an unexpected antioxidant activity., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Ternary nanocomposites, including graphene oxide (GO), hydroxyapatite (HAP), and cadmium selenite (CdSe) have been encapsulated into nanofibrous scaffolds of polylactic acid. These compositions were indexed as HAP@PLA (C1), CdSe@PLA (C2), HAP/CdSe@PLA (C3), HAP/GO@PLA (C4), and HAP/CdSe/GO@PLA (C5). Structural confirmation is executed by XRD and XPS techniques, while FESEM performs morphological characteristics. CdSe and GO dopants cause a significant increase in nanofiber diameter, HAP/GO@PLA (C4), showing thin surface fibers with fiber diameter up to 3.1 μm, followed by HAP/CdSe/GO@PLA (C4) composite that belongs to filament size up to 2.1 μm. On the other hand, the mechanical properties reveal that the dual dopant composites HAP/CdSe@PLA (C3) and HAP/GO@PLA (C4) hit the maximum tensile fracture values with 1.49 ± 0.3 and 0.99 ± 0.2 MPa. Further, the ternary C5 composite represents the lowest contact angle of 86.1 ± 3.7°. The antibacterial activity increased from 32.4 ± 9.7 and 28.4 ± 6.5% to be 85.3 ± 4.6 and 88.1 ± 5.6% for C1 and C5, respectively, against both E. coli and S. aureus in dark conditions. Moreover, the antibacterial potency enhanced from 75.4 ± 7.6 to be 83.5 ± 6.5 from dark to light conditions against E. coli for the composition of PLA containing the binary composition of HAP/CdSe., (Copyright © 2021 Elsevier B.V. All rights reserved.)

To explore in vivo application of quantum dots (QDs), it is essential to understand the dynamics and energetics of interactions between QDs and proteins. Here, surface plasmon resonance (SPR) and molecular docking were employed to investigate the kinetics and thermodynamics of interactions between human serum albumin (HSA) and CdTe QDs (~3 nm) functionalized with mercaptopropionic acid (MPA) or thioglycolic acid (TGA). Kinetic analysis showed that HSA-QD interactions involved transition-complex formation. Despite the structural similarities between MPA and TGA, the [HSA-CdTe@TGA] ‡ formation by association of free HSA and QDs demanded 70% more energy and higher entropic gain (E a-TGA ‡ = 65.10 and T∆S a-TGA ‡ = 28.62 kJ mol -1 ) than the formation of [HSA-CdTe@MPA] ‡ (E a-MPA ‡  = 38.13 and T∆S a-MPA ‡  = 0.53kJ mol -1 ). While the [HSA-CdTe@MPA] ° dissociation required higher energy and lower entropy loss (E d-MPA ‡  = 49.96 and T∆S d-MPA ‡  = - 32.18kJ mol -1 ) than the [HSA-CdTe@TGA] ° dissociation (E d-TGA ‡ = 30.78 and T∆S d-TGA ‡ = - 51.12 kJ mol -1 ). The stability of [HSA-QDs] ° was independent of the temperature and functionalizing group. However, the enthalpic and entropic components were highly affected by the substitution of MPA (ΔH° = - 11.83 and TΔS° = 32.72 kJ mol -1 ) with TGA (ΔH° = 34.31 and TΔS° = 79.73 kJ mol -1 ). Furthermore, molecular docking results indicated that the metal site on the QDs contributes to the stabilization of [HSA-QDs] ° . Therefore, differences in QD functionalization and surface coverage densities can alter the HSA-QD interaction, thus their application., (Copyright © 2021. Published by Elsevier B.V.)

Polyvinyl-pyrrolidone capped spherical cadmium sulphide quantum dots (CdS-PVP QDs), 2-6 nm in size, were developed as a selective turn-on fluorescence nanosensor for monohydrogen phosphate ion (HPO 4 2- ) in aqueous medium. Fluorescence intensity of CdS-PVP QDs significantly increased with addition of HPO 4 2- ions, whereas the other common inorganic ions had very little effect on the fluorescence intensity. The proposed sensor may be efficiently used for the detection of HPO 4 2- ions at a low level of concentration up to 213 nM in real urine sample. Cell imaging study indicates that the CdS-PVP QDs are cell permeable and can detect the intracellular distribution of HPO 4 2- ions under fluorescence microscope. The CdS-PVP QDs showed considerable activity against Staphylococcus aureus also., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

ZnS quantum dots (QDs) and their core/shell (CdSe/ZnS) structures were studied for Zn based precursor reactivities. ZnS and CdSe/ZnS QDs were prepared selecting aqueous route and then characterized via XRD, TEM, EDX, PL, RAMAN and FTIR practices. Core/shell nanostructures were synthesized by taking dissimilar precursors for the shell formation. Photoluminescence spectra of prepared QDs corroborate the effectual luminescence. Prepared QDs have large surface area that make them useful alternative as organic antimicrobial agent which are highly irritant and unstable. Study of antimicrobial behavior of QD structures was carried out by disk diffusion method. Antimicrobial study of QDs and their core/shell structures was performed against gram negative and gram positive bacteria, E. coli, A. baumanni and Bacillus subtilis respectively. It is found that elemental composition and size of QDs plays important role in antimicrobial behavior. Prepared QDs are fluorescent and have a key role in complex microbial population studies and identification of bacteria., (Copyright © 2018. Published by Elsevier B.V.)

Cadmium oxide nanoparticles (CdO NPs) are among some of the most studied and industrially used metal oxide NPs. They have been widely used for industrial application, such as paint pigments and electronic devices, and medical therapeutics. With increasing use of CdO NPs and concerns for their potential adverse effects on the environment and public health, evaluation of the cytotoxicity and genotoxicity of CdO NPs becomes very important. To date, there is a limited understanding of the potential hazard brought by CdO NPs and a lack of information and research, particularly on the genotoxicity assessment of these NPs. In this study, 10 nm CdO core-PEG stabilized NPs were synthesized, characterized and used for evaluation of CdO NPs' cytotoxicity and genotoxicity. Release of cadmium ions (Cd +2 ) from the CdO NPs in cell culture medium, cellular uptake of the NPs, and the endotoxin content of the particles were measured prior to the toxicity assays. Cytotoxicity was evaluated using the MTS assay, ATP content detection assay, and LDH assay. Genotoxicity was assessed using the Ames test, Comet assay, micronucleus assay, and mouse lymphoma assay. The cytotoxicity of cadmium chloride (CdCl 2 ) was also evaluated along with that of the CdO NPs. The results showed that endotoxin levels within the CdO NPs were below the limit of detection. CdO NPs induced concentration-dependent cytotoxicity in TK6 and HepG2 cells with the MTS, ATP and LDH assays. Although the genotoxicity of CdO NPs was negative in the Ames test, positive results were obtained with the micronucleus, Comet, and mouse lymphoma assays. The negative response of CdO NPs with the Ames test may be the result of unsuitability of the assay for measuring NPs, while the positive responses from other genotoxicity assays suggest that CdO NPs can induce chromosomal damage, single or double strand breaks in DNA, and mutations. The toxicity of the CdO NPs results from the NPs themselves and not from the released Cd +2 , because the ions released from the NPs were minimal. These results demonstrate that CdO NPs are cytotoxic and genotoxic and provide new insights into risk assessment of CdO NPs for human exposure and environmental protection., Competing Interests: Declaration of Competing Interest The authors declare that there are no conflicts of interest., (Published by Elsevier B.V.)

A green, efficient synthesis of cadmium oxide decorated reduced graphene oxide nanocomposites (RGO/CdO) was prepared by one-step co-precipitation and hydrothermal method. Crystalline nature of the nanocomposites was characterized by X-ray diffraction analysis. To evaluate the structural morphology and particle size, high resolution transmission electron microscopy were used. X-ray photoelectron spectroscopy, Raman spectroscopy and Fourier transform infrared spectroscopy techniques were employed to establish chemical structure of the nanocomposites and Atomic Force Microscopy was done to measure the thickness. The optical properties were evaluated by UV-visible absorption spectroscopy. Thermo-gravimetric analysis, BET surface area and zeta potential measurements were carried out to study the thermal and surface characteristics. The CdO nano-particles (NPs) decorated on RGO sheets exhibit better electrical conductivity compared to RGO. The antibacterial activity of the nanocomposites has also been monitored in different culture media imparting good potentiality than RGO., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Recyclable magnetic photocatalysts of iron oxide (IO)/CdS core/shell nanocrystals (CSNCs) were prepared by a facile sequential one-pot method using 3, 3'-thiobispropanoic acid (TDP) as a bridge. The CSNCs showed redshift in absorption edge, decrease in the optical band gap, reduced exciton decay rates and increment in particle size. Quenching studies have been employed to understand the position of the electron/hole wave-functions at the IO/CdS interface. Antimicrobial tests have also been performed using broth tube dilution and disc diffusion methods against S. aureus. Additionally, photocatalytic properties of IO/CdS CSNCs have been evaluated for the decomposition of xylenol blue. In comparison with CdS quantum dots (QDs) and iron oxide nanoparticles (IONPs), the IO/CdS CSNCs showed improved photocatalytic and bactericidal activities. Finally, levels of oxidative damage to proteins and lipids were evaluated., (Copyright © 2018. Published by Elsevier B.V.)

Fluorescent inorganic quantum dots are highly promising for biomedical applications as sensing and imaging agents. However, the low internalization of the quantum dots, as well as for most of the nanoparticles, by living cells is a critical issue which should be solved for success in translational research. In order to increase the internalization rate of inorganic CdSe/ZnS quantum dots, they were functionalized with a fluorinated organic ligand. The fluorinated quantum dots displayed an enhanced surface activity, leading to a significant cell uptake as demonstrated by in vitro experiments with HeLa cells. We combined the experimental and computational results of Langmuir monolayers of the DPPC phospholipid as a model cell membrane with in vitro experiments for analyzing the mechanism of internalization of the fluorinated CdSe/ZnS quantum dots. Surface pressure-molecular area isotherms suggested that the physical state of the DPPC molecules was greatly affected by the quantum dots. UV-vis reflection spectroscopy and Brewster Angle Microscopy as in situ experimental techniques further confirmed the significant surface concentration of quantum dots. The disruption of the ordering of the DPPC molecules was assessed. Computer simulations offered detailed insights in the interaction between the quantum dots and the phospholipid, pointing to a significant modification of the physical state of the hydrophobic region of the phospholipid molecules. This phenomenon appeared as the most relevant step in the internalization mechanism of the fluorinated quantum dots by cells. Thus, this work sheds light on the role of fluorine on the surface of inorganic nanoparticles for enhancing their cellular uptake., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Signaling by glutamatergic synapses plays an important role in visual processing in the retina. In this study, we used an enzyme-linked fluorescence assay system to monitor the dynamics of extracellular glutamate in a slice preparation from the mouse retina. High K stimulation induced an elevation of fluorescence in the inner plexiform layer (IPL) of the retina when glutamate transporters were inhibited by dl-threo-β-benzyloxyaspartic acid (TBOA). The high K-induced fluorescence signals in the IPL were inhibited by the calcium channel blocker Cd 2+ . Blockade of GABAergic and glycinergic circuits by picrotoxin and strychnine also elevated the fluorescence signals in the IPL. Thus, the enzyme-linked fluorescence assay system might be useful for monitoring the bulk concentration of extracellular glutamate released by synapses in the inner retina., (Copyright © 2018 Elsevier B.V. and Japan Neuroscience Society. All rights reserved.)

Nanoparticles (NPs) are inevitably released into the aquatic environment for being widely used and may affect the toxicity of other contaminants already present in the environment, such as trace metals. However, the effects of NPs on the ecotoxicity of cadmium (Cd), a common environmental trace metal pollutant, are not well explored. In this study, effects of four widely used NPs TiO 2 (n-TiO 2 ), SiO 2 (n-SiO 2 ), Ag (n-Ag) and CdTe/CdS core/shell quantum dots (QD) on the toxicity of Cd to the freshwater algae Chlamydomonas reinhardtii were assessed respectively. Cd reduced the algae biomass, impaired the photosynthetic activities, and led to intracellular oxidative stress of algae. At non-toxic concentrations, both n-TiO 2 (100 mg L -1 ) and n-SiO 2 (400 mg L -1 ) attenuated the toxicity of Cd towards the algae for reducing the intracellular Cd contents, and the former was more pronounced. QD (0.5 mg L -1 ) increased the toxicity of Cd to algae, but n-Ag (0.2 mg L -1 ) had no significant influence on the Cd toxicity to algae. The microscopic observations on the ultrastructure of algae cells presented the same phenomena and n-TiO 2 , n-SiO 2 aggregations were clearly observed outside the cell wall. Furthermore, the regulation of NPs to the Cd toxicity towards algae was related to the intracellular nitric oxide (NO), an important signaling molecule, rather than the phototaxis of algae. Above all, this study provided a basic understanding about the difference in joint toxicity of different kinds of NPs and Cd to aquatic organisms., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Cadmium selenide (CdSe) based quantum dots modified with polyethylene glycol and chemically linked to interleukin-13 (IL13) were prepared with the aim of identifying the high affinity receptor (IL13Rα2) which is expressed in glioma stem cells and exosomes secreted by these cancer stem cells. IL13 conjugated quantum dots (IL13QD) were thoroughly characterized for their physicochemical properties including particle size and surface morphology. Furthermore, the specific binding of the IL13QD to glioma cells and to glioma stem cells (GSC) was verified using a competitive binding study. The exosomes were isolated from the GSC conditioned medium and the expression of IL13Rα2 in the GSC and exosomes was verified. The binding property of IL13QD to the tumor associated exosomes was initially confirmed by transmission electron microscopy. The force of attraction between the quantum dots and U251 glioma cells and the exosomes was investigated by atomic force microscopy, which indicated a higher force of binding interaction between the IL13QD and IL13Rα2 expressing glioma cells and exosomes secreted by glioma stem cells. Flow cytometry of the IL13QD and exosomes from the culture media and cerebrospinal fluid (CSF) of patients with glioma tumors indicated a distinctly populated complex pattern different from that of non-targeted quantum dots and bovine serum albumin (BSA) conjugated quantum dots confirming specific binding potential of the IL13QD to the tumor associated exosomes. The results of this study demonstrate that IL13QD can serve as an ex vivo marker for glioma stem cells and exosomes that can inform diagnosis and prognosis of patients harboring malignant disease., Statement of Significance: Functionalized quantum dots are flexible semiconductor nanomaterials which have an immense application in biomedical research. In particular, when they are functionalized with biomolecules like proteins or antibodies, they have the specialized ability to detect the expression of receptors and antigens in cells and tissues. In this study we designed a cytokine (interleukin-13) functionalized quantum dot to detect a cancer associated receptor expressed in cancer stem cells and the extracellular vesicles (exosomes) secreted by the cancer cells themselves. The binding pattern of these cytokine modified quantum dots to the cancer stem cells and exosomes alters the physical properties of the complex in the fixed and suspended form. This altered binding pattern can be monitored by a variety of techniques, including transmission electron microscopy, atomic force microscopy and flow cytometry, and subsequent characterization of this quantum dot binding profile provides useful data that can be utilized as a fingerprint to detect cancer disease progression. This type of functionalized quantum dot fingerprint is especially useful for invasive cancers including brain and other metastatic cancers and may allow for earlier detection of disease progression or recurrence, thus saving the lives of patients suffering from this devastating disease., (Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

The size and shape dependent semiconductor quantum dots (0D nanoparticles) with color tunability demonstrating significant influence in a biological system and considered as ideal probes. Here, a non-coordinated colloidal approach was used for the synthesis of CdSe, CdSe/ZnS and CdSe/CdS core-shell quantum dots (QDs) of 3-4nm. The synthesized nanocrystals show a high crystallinity, examined by X-ray diffraction (XRD) and high-resolution electron microscopy (HRTEM). The core-shell semiconductor QDs exhibit stronger photoluminescence (PL) as compared to the core QDs. The strong PL with small full-width half maximum (FWHM) indicates that the prepared QDs have a nearly uniform size distribution and well dispersibility. The quantum yield (QY) of core-shell QDs increases due to the surface passivation. Further, the PL of BSA is quenched strongly by the presence of core-shell QDs and follows the well-known Stern-Volmer (S-V) relation, whereas the PL lifetime does not follow the S-V relation, demonstrating that the observed quenching is predominantly static in nature. Among CdSe core, CdSe/ZnS and CdSe/CdS core-shell QDs, the CdSe/ZnS QDs shows the least cytotoxicity and most biocompatibility. Thus, the prepared core-shell QDs are biocompatible and exhibit strong sensing ability., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Quercetin (Qe) plays an important role in inflammation, antibacterial, anticancer, and aging. However, Qe has extremely low water solubility, which is a major challenge in drug absorption. In this study, we described a simple method for synthesis of Qe/CdSe/ZnS nanoparticles (QCZ NPs). The QCZ NPs had an average diameter of 10nm and prominent yellow emission under UV irradiation. We investigated the antibacterial activity of QCZ NPs against drug-resistant Escherichia coli (E. coli) and Bacillus subtilis (B. subtilis) in vitro. Results showed that QCZ NPs had considerably more effective antibacterial activities than Qe or CdSe nanoparticles (CdSe NPs). Antibacterial experiment results showed that QCZ NPs acted against E. coli and B. subtilis by disrupting the bacterial cell wall and membrane. In vivo study, the QCZ NPs could cure inflammation and lesion which caused by E. coli. In anticancer assays, the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] cell proliferation assays exhibited the cytotoxicity of QCZ NPs increased approximately 2-6 fold compared to raw Qe and CdSe NPs. Moreover, by using RT-CES (real-time cell electronic sensing) studies, we had demonstrated QCZ NPs have also an effect on migration and proliferation of BGC-823 cells. CdSe NPs loaded with Qe, these QCZ NPs exhibited excellent antibacterial (E. coli and B. subtilis) and anticancer (BGC-823) activities., (Copyright © 2016 Elsevier Inc. All rights reserved.)

The nanotoxicity of Cd-containing quantum dots (QDs) for biomedical applications is very controversial and not completely understood. In this study, we evaluated the cytotoxicity of surface-biofunctionalized CdS QDs with chitosan directly synthesized via aqueous route at room temperature. These core-shell CdS-chitosan nanoconjugates showed different degrees of cytotoxic responses using MTT cell proliferation assay toward three human cell cultures, human osteosarcoma cell line (SAOS), non-Hodgkin's B cell lymphoma (Toledo), and human embryonic kidney cell line (HEK293T), under three exposure times (1, 3, and 5days) and three colloidal concentrations (10nM, 50nM, and 100nM). The results clearly demonstrated that the CdS QDs, regardless to the fact that they were coated with a biocompatible aminopolysaccharide shell, induced a severe dose- and time-dependent inhibition of cell viability. In addition, the HEK293T and SAOS cell lines showed much more sensitive response compared to Toledo, which indicated that the cytotoxicity was also cell-type dependent. The exceptional resistance of Toledo cells to toxic effects of CdS nanoconjugates even at severe test conditions was assigned to specific role of B-lineage cells of the immune defense system. Remarkably, no conclusive evidence of toxicity of CdS nanoconjugates was observed in vivo using intravenous injections of CdS nanoconjugates in BALB/c mouse animal models for 30days, but localized fluorescence was detected in ex-vivo liver tissue samples. Therefore, these results prove that there is no guarantee of "risk-free" use of CdS nanoconjugates for in vivo applications, even when functionalized with biopolymer ligands, as they can pose an excessive threat due to unpredicted and uncorrelated responses under in vitro and in vivo biological assays with highly toxic cadmium ions., (Copyright © 2016 Elsevier B.V. All rights reserved.)

In this research, a chemical precipitation method was used to synthesize undoped and doped cadmium oxide nanoparticles and studied by TG-DTA, XRD, FT-IR, SEM, with EDX and antibacterial activities, respectively. The melting points, thermal stability and the kinetic parameters like entropy (ΔS), enthalpy (ΔH), Gibb's energy (ΔG), activation energy (E), frequency factor (A) were evaluated from TG-DTA measurements. X-ray diffraction analysis (XRD) brought out the information about the synthesized products exist in spherical in shape with cubic structure. The functional groups and band area of the samples were established by Fourier transform infrared (FT-IR) spectroscopy. The direct and indirect band gap energy of pure and doped samples were determined by UV-Vis-DRS. The surface morphological, elemental compositions and particles sizes were evaluated by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). Finally, antibacterial activities indicated the Gram-positive and Gram-negative bacteria are more active in transporter, dehydrogenize and periplasmic enzymatic activities of pure and doped samples., (Copyright © 2015 Elsevier B.V. All rights reserved.)

CdO-ZnO nanocomposite was prepared by microwave-assisted method and characterized by X-ray crystallography (XRD), Scanning Electron Microscopy (SEM) and Fourier Transform Infrared Spectroscopy (FT-IR). It exhibits hexagonal cubic structure with an average crystallite size of 27 nm. From the UV-Vis spectra, the bandgap is estimated as 2.92 eV. The fluorescence spectrum shows a near band edge emission at 422 nm. In addition the antibacterial activity of CdO-ZnO nanocomposite was carried out in-vitro against two kinds of bacteria: gram negative bacteria (G -ve) i.e. Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae and gram positive bacteria (G +ve): Staphylococcus aureus, Proteus vulgaris and Bacillus spp. This study indicates the zone of inhibition of 40 mm has high antibacterial activity towards the gram positive bacterium S. aureus., (Copyright © 2014 Elsevier B.V. All rights reserved.)

In the present study, synthesized pure and Ag (1%, 2%, and 3%) doped Cadmium Oxide (CdO) nanoparticles by chemical precipitation method. Then, the synthesized products were characterized by thermo gravimetric-differential thermal analysis (TG-DTA), X-ray diffraction (XRD) analysis, Fourier transform infrared (FT-IR) spectroscopy, Ultra violet-Vis diffused reflectance spectroscopy (UV-Vis-DRS), Scanning electron microscopy (SEM), Energy dispersive X-rays (EDX) spectroscopy, and anti-bacterial activities, respectively. The transition temperatures and phase transitions of Cd(OH)2 to CdO at 400°C was confirmed by TG-DTA analysis. The XRD patterns show the cubic shape and average particle sizes are 21, 40, 34, and 37nm, respectively for pure and Ag doped samples. FT-IR study confirmed the presence of CdO and Ag at 677 and 459cm(-1), respectively. UV-Vis-DRS study shows the variation on direct and indirect band gaps. The surface morphologies and elemental analysis have been confirmed from SEM and with EDX. In addition, the synthesized products have been characterized by antibacterial activities against Gram-positive and negative bacteria. Further, the present investigation suggests that CdO nanoparticles have the great potential applications on various industrial and medical fields of research., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Synthesis of magnetic Fe3O4/SiO2/graphene-CdTe QDs/chitosan nanocomposites (FGQCs) is investigated with respect to their potential of improving the drug loading content above that of magnetic/fluorescent bifunctional nanocomposites. To evaluate the performance of the FGQCs, their surface morphology was thoroughly assessed. The in vitro interaction between the FGQCs and heptoma cell line smmc-7721 cells was observed for the first time by TEM ultrathin section imaging. At an excitation wavelength of 365 nm, the graphene-QDs exhibit a strong luminescence in aqueous environments. The loading content and entrapment efficiency of the FGQCs were 70% and 50%, respectively. The cytotoxicity of this novel drug delivery system was evaluated in vitro using heptoma cell line smmc-7721 and quantified by the 3-(4,5-dimethylthiazol-z-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The results show that FGQCs are a promising new multifunctional material for drug delivery in biological and medical applications., (Copyright © 2013 Elsevier B.V. All rights reserved.)

In the present work, the CdSe/ZnS hydrophobic quantum dots were embedded within the polyelectrolyte nanocapsules. The core of the capsules, which consists of a mixture of the linseed oil with chloroform, was prepared using the spontaneous emulsification technique. The obtained emulsions were stabilized with lecithin and encapsulated using the layer-by-layer (LbL) adsorption of polyelectrolytes. The pair of biocompatible polyelectrolytes was used: the cationic poly-l-lysine hydrobromide (PLL) together with the anionic poly-d-glutamic acid sodium salt. The saturation LbL method, which is based on the stepwise formation of consecutive layers on the initial emulsion without the intermediate rinsing step, was applied to form the capsule shells. Their growth was evidenced by the capsule size and electrophoretic mobility measurements. The emulsion and the capsules were deposited on a mica surface and the deposit topology was examined by the means of atomic force microscopy (AFM). The presence of quantum dots within the oil cores was confirmed by recording the fluorescent spectra of the samples containing CdSe/ZnS. In order to evaluate cytotoxicity of the capsules, their influence on the viability of mouse embryonic fibroblasts was examined using the MTT test, followed by optical-microscope observation of morphology of the cells after hematoxylin-eosin staining., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Although cadmium (Cd) is a widespread environmental contaminant and human carcinogen, our studies indicate an organic Cd complex to be a potent inhibitor of proteasomal chymotrypsin-like (CT-like) activity, further capable of inducing apoptosis in a cancer cell-specific manner. It has been reported that the ligands indole-3-butyric acid (L1) and indole-3-propionic acid (L2) have cancer-fighting effects when tested in a rat carcinoma model. In addition, 3, 5-diaminobenzoic acid o-vanillin Schiff bases (L3) have high antimicrobial activity and a large number of Schiff base complexes have been reported to have proteasome-inhibitory activity. We therefore hypothesized that synthetic forms of Cd in combination with L1, L2 and L3 may have proteasome-inhibitory and apoptosis-inducing activities, which would be cancer cell-specific. To test this hypothesis, we have synthesized three novel Cd-containing complexes: [Cd2(C12H12O2N)4(H2O)2]·2H2O (Cd1), [Cd2(C11H10O2N)4(H2O)2]·2H2O (Cd2) and [Cd(C7H4N2O2)(C8H6O2)2]·2H2O (Cd3), by using these three ligands. We sought out to characterize and assess the proteasome-inhibitory and anti-proliferative properties of these three Cd complexes in human breast cancer cells. Cd1, Cd2 and Cd3 were found to effectively inhibit the chymotrypsin-like activity of purified 20S proteasome with IC50 values of 2.6, 3.0 and 3.3 μΜ, respectively. Moreover, inhibition of cancer cell proliferation also correlated with this effect. As a result of proteasomal shutdown, the accumulation of ubiquitinated proteins and the proteasome target IκB-α protein as well as induction of apoptosis were observed. To account for the cancer specificity of this effect, immortalized, non-tumorigenic breast MCF10A cells were used under the same experimental conditions. Our results indicate that MCF10A cells are much less sensitive to the Cd1, Cd2 and Cd3 complexes when compared to MDA MB 231 breast cancer cells. Therefore, our study suggests that these Cd organic complexes are capable of inhibiting tumor cellular proteasome activity and consequently induce cancer cell-specific apoptotic death., (Copyright © 2013 Elsevier Inc. All rights reserved.)

The growing demand for semiconductor [quantum dots (Q-dots)] nanoparticles has fuelled significant research in developing strategies for their synthesis and characterization. They are extensively investigated by the chemical route; on the other hand, use of microbial sources for biosynthesis witnessed the highly stable, water dispersible nanoparticles formation. Here we report, for the first time, an efficient fungal-mediated synthesis of highly fluorescent CdTe quantum dots at ambient conditions by the fungus Fusarium oxysporum when reacted with a mixture of CdCl2 and TeCl4. Characterization of these biosynthesized nanoparticles was carried out by different techniques such as Ultraviolet-visible (UV-Vis) spectroscopy, Photoluminescence (PL), X-ray Diffraction (XRD), X-ray Photoelectron spectroscopy (XPS), Transmission Electron Microscopy (TEM) and Fourier Transformed Infrared Spectroscopy (FTIR) analysis. CdTe nanoparticles shows antibacterial activity against Gram positive and Gram negative bacteria. The fungal based fabrication provides an economical, green chemistry approach for production of highly fluorescent CdTe quantum dots., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Novel hierarchical TiO(2)/CdS "spindle-like" composites with uniform distribution of CdS nanocrystals on nanoporous TiO(2) mesocrystals were successfully prepared by hydrothermal and hot-injection methods. In this work, the optimal mass ratio of Ti/Cd is determined to be 2 of as-synthesized TiO(2)/CdS composites. This TiO(2)/CdS composite exhibits excellent photocatalytic activity in the degradation of Rhodamine B (RhB) and photocatalytic reaction constant is 10 times higher than that of TiO(2), 3.5 times higher than that of CdS and higher than other TiO(2)/CdS composites with different amount of Ti/Cd mass ratio. In addition, TiO(2)/CdS with optimal amount of CdS kills 99.9% of Escherichia coli in 10 min under visible-light irradiation, which shows significant higher efficiency than pure TiO(2), CdS and other TiO(2)/CdS composites. The excellent performances of this hierarchical composite are ascribed to its outstanding properties, including large specific surface area (BET), high crystallinity of oriented single-crystal-like nanoporous TiO(2) mesocrystals for charge transfer, retarded recombination of photogenerated electron-hole pairs via isolating electrons and holes in two different materials, and extended photo response of this hierarchical composite to the visible region. Considering all these superior properties and abilities, this hierarchical TiO(2)/CdS "spindle-like" composite will show great potential for applications in the water purification field., (Copyright © 2012 Elsevier B.V. All rights reserved.)

In this paper, different sizes of glutathione-capped CdTe (GSH/CdTe) quantum dots (QDs) have been prepared directly in aqueous solution. The QDs have tunable fluorescence in the range of 510-670 nm, and they also have high photoluminescence quantum yield (PLQY) without any postpreparative treatment. Furthermore, the QDs have strong resistance to photobleaching, and they also have to be considered as cytocompatible. In addition, for the first time, folic acid was covalently conjugated to the GSH/CdTe QDs for imaging of cancer cells, demonstrating their potentially broad application as biolabels., (Copyright © 2010 Elsevier B.V. All rights reserved.)

Three new Cd(II) complexes with the Schiff base ligand derived from the condensation 1+2 of 2,6-diacetylpyridine and 5,6-diamino-1,3-dimethyluracil have been "in template" synthesized. The molecular structures of complexes were determined by single-crystal X-ray diffraction. The metal center shows a very distorted mer-bis-tridentate CdN(6) octahedral geometry as consequence of the reduced bite angles of the ligand and the existence of long-distanced interactions with donor atoms in the neighbourhood. The luminescent properties of complexes in CH(3)CN solution were investigated showing the emission energies depend on the uracil part of the ligand. The evaluation of their biological properties against C6 glioma cell line indicates that cadmium(II) complexes could be an interesting tools to treat drug-resistant brain tumors.

Based on the strong enhancement effect of silver ion on resonance light-scattering intensity of functional CdS nanoparticles, a new direct quantitative determination method for silver ion was established. Under the optimum conditions, the response signal is linearly proportional to the concentration of silver ion. The linear range is 5.0x10(-9)-2.0x10(-6) mol L(-1). The proposed method was applied to determine silver ion in river water samples.

Quantum dots (QDs) are luminescent nanoparticles with unique optical properties that have been exploited for single-cell and whole-animal imaging. When coated with proteins or biocompatible polymers, QDs are not deleterious to cells and organisms. However, when QDs are retained in cells or accumulated in the body for a long period of time, their coatings may be degraded, yielding "naked" QDs. Here, we show that "naked" QDs induce damage to the plasma membrane, mitochondrion, and nucleus, leading to cell death. Reactive oxygen species (ROS) are important players in mediating QD-induced cellular damage. QD-induced cytotoxicity can be reduced or even eliminated without covalent binding of protective agents to the QD surface. Results from these studies suggest the critical role of several subcellular compartments in QD-induced cytotoxicity and point toward multiple molecular targets in nonclassical apoptosis.

Thirty-seven metal compounds were examined for inhibitory activities against infection with human immunodeficiency virus type 1 (HIV-1). Zinc group metal compounds, namely, zinc acetate, zinc chloride, zinc nitrate, cadmium acetate and mercury chloride, showed anti-HIV-1 activities. Cadmium and mercury compounds at 1-10 microg/ml and zinc compounds at 100 microg/ml strongly inhibited HIV-1 infection, although the cadmium, mercury and zinc compounds had severe cytotoxities at 100, 100 and 1000 microg/ml, respectively. They inhibited transcription of HIV-1 RNA and HIV-1 production at concentrations at which they did not affect the growth of HIV-1-producing cells. They had little effect on syncytium formation resulting from cocultivation of uninfected with HIV-1-producing cells. Nor did they affect HIV-1 DNA synthesis following HIV-1 infection. The metal compounds may owe their anti-HIV-1 effects to inhibition of HIV-1 DNA to RNA transcription, rather than inhibition of the adsorption, penetration or reverse transcription step of HIV-1 infection.

A 90 kDa cellular protein in a fish cell, CHSE-214, showed increased expression by the infection of infectious hematopoietic necrosis virus (IHNV), heat shock, 2-mercaptoethanol, copper sulfate, and cadmium sulfate, and was detected in various kinds of cells such as human, rat, and mouse cells. The molecular mass of the 90 kDa protein was different from those of the hsp90 and grp94. In addition, all the anti-stress protein MAbs did not react with the 90 kDa protein. Finally, the subcellular distribution of the 90 kDa protein, determined by Western blots of subcellular fractions, was found to be mainly nuclear, both in normal and IHNV-infected CHSE-214 cells. The present results indicate that the 90 kDa protein is a kind of stress protein. However, based on its molecular mass, antigenic characteristics, and subcellular distribution, it is likely that this protein is a novel stress protein that has not been previously described in animal systems, especially in fish systems.

With an objective to determine the period of persistence of the metal-induced adaptive response to chemical mutagens and heavy metals, growing root meristems of Allium cepa were conditioned by cadmium sulfate (CdSO4), 4 x 10(-7) and 4 x 10(-6) M for 1 h and subsequently challenged by maleic hydrazide (MH), 5 x 10(-3) M or methyl mercuric chloride (MMCl), 1.26 x 10(-6) M for 3 h at different time intervals ranging from a few minutes to several hours following the conditioning dose. Root meristems, fixed at regular intervals during recovery from 6 to 48 h, were cytologically analysed for cells with micronuclei (MNC). The adaptive responses to MH and MMCl were observed as early as 5 min after the Cd-conditioning that persisted for at least 48 h. Metabolic inhibitors, cycloheximide (CH). 10(-7) M and buthionine sulfoximine (BSO), 10(-4) M administered either prior to or simultaneous with Cd-conditioning effectively prevented the adaptive response to MH. Whereas BSO, an inhibitor of phytochelatin synthesis, prevented the adaptive responses from 15 min to 8 h after the conditioning dose, CH an inhibitor of cytoplasmic protein synthesis prevented the same from 6 to 48 h. The findings underscored the differential roles of phytochelatins and proteins underlying the foregone metallo-adaptive response.

Synchronized V79 cells were treated before entering mitosis with known and suspicious mitotic arrestants and analyzed by flow cytometry and by light microscopy. Colcemid, nocodazole, vinblastine, diethylstilbestrol, triethyl lead and cadmium sulfate caused a dose dependent mitotic arrest of up to 80%, in comparison with 6% for the controls. Mixtures of polycyclic aromatic hydrocarbons and heterocyclic compounds induced a mitotic arrest of 50%-60%. Extracts of airborne particulates revealed a mitotic arrest of 10%-40%. In contrast, benzoquinone and hydroquinone led to a G2-block rather than to a mitotic arrest. Results of flow cytometry measurements correlated well with those obtained by light microscopy. Cell synchronization in combination with flow cytometry seems to be of considerable value as a rapid method for testing nongenotoxic agents with mitotic arresting activity.