Green hydrothermal synthesis and characterization of Ag2O-supported MgO/rGO nanocomposites by using Phoenix leaf extract: a promising approach for enhanced photocatalytic and anticancer activities.

The present work was designed to synthesize Ag2O-supported MgO/rGO nanocomposites (NCs) via green method using Phoenix leaf extract for improved photocatalytic and anticancer activity. Green synthesized Ag2O-supported MgO/rGO NCs were characterized through X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS), Raman, ultraviolet-visible (UV-vis) spectroscopy, and photoluminescence (PL) spectroscopy, and gas chromatography-mass spectroscopy (GC-MS) was applied to examine the chemical components of the Phoenix leaf extract. Characterization data confirmed the preparation of MgO NPs, Ag2O-MgO NCs, and Ag2O-MgO/rGO NC with particle size of 26-28 nm. UV-vis study exhibited that the band gap energy of MgO NPs, Ag2O-MgO NCs, and Ag2O-MgO/rGO NC were in the range of 3.53-3.43 eV. The photocatalytic results showed that the photodegradation of Rh B dye of Ag2O-supported MgO/rGO NCs (82.81%) was significantly higher than pure MgO NPs. Additionally, the biological response demonstrates that the Ag2O-supported MgO/rGO NCs induced high cytotoxicity against MCF-7 cancer cells for 24 h and 48 h compared with both pure MgO NPs and Ag2O-MgO NCs. This study suggests that the adding of Ag2O and rGO sheets played significant role in the enhanced photocatalytic and anticancer performance of MgO NPs.

Green synthesis of ZnO-TiO2/RGO nanocomposites using Senna surattensis extract: a novel approach for enhanced anticancer efficacy and biocompatibility.

The purpose of the present study is to enhance the anticancer and biocompatibility performance of TiO2 NPs, ZnO NPs, ZnO-TiO2 (NCs), and ZnO-TiO2/reduced graphene oxide (RGO) NCs against two types of human cancer (HCT116) and normal (HUVCE) cells. A novel procedure for synthesizing ZnO-TiO2/RGO NCs has been developed using Senna surattensis extract. The improved physicochemical properties of the obtained samples were investigated using different techniques such as XRD, TEM, SEM, XPS, FTIR, DLS and UV-visible spectroscopy. XRD results showed that the addition of ZnO and RGO sheets affects the crystal structure and phase of TiO2 NPs. SEM and TEM images displayed that the TiO2 NPs and ZnO NPs were small with uniform spherical morphology in the prepared ZnO-TiO2/RGO NCs. Besides, it is shown that ZnO-TiO2 NCs anchored onto the surface of RGO sheets with a particle size of 14.80 ± 0.5 nm. XPS data confirmed the surface chemical composition and oxidation states of ZnO-TiO2/RGO NCs. Functional groups of prepared NPs and NCs were determined using FTIR spectroscopy. DLS data confirmed that the addition of ZnO and RGO sheets improves the negative surface charge of the prepared pure TiO2 NPs (-22.51 mV), ZnO NPs (-18.27 mV), ZnO-TiO2 NCs (-30.20 mV), and ZnO-TiO2/RGO NCs (-33.77 mV). Optical analysis exhibited that the bandgap energies of TiO2 NPs (3.30 eV), ZnO NPs (3.33 eV), ZnO-TiO2 NCs (3.03 eV), and ZnO-TiO2/RGO NCs (2.78 eV) were further enhanced by adding ZnO NPs and RGO sheets. This indicates that the synthesized samples can be applied to cancer therapy and environmental remediation. The biological data demonstrated that the produced ZnO-TiO2/RGO NCs show a more cytotoxic effect on HCT116 cells compared to pure TiO2 NPs and ZnO-TiO2 NCs. On the other hand, these NCs displayed the lowest level of toxicity towards normal HUVCE cells. These results indicate that the ZnO-TiO2/RGO NCs have strong toxicity against HCT116 cells and are compatible with normal cells. Our results show that the plant extract enhanced the physicochemical properties of NPs and NCs compared with the traditional chemical methods for synthesis. This study could open new avenues for developing more effective and targeted cancer treatments.

One-step preparation, characterization, and anticancer potential of ZnFe2O4/RGO nanocomposites.

Zinc ferrite nanoparticles (ZnFe2O4 NPs) have attracted extensive attention for their diverse applications including sensing, waste-water treatment, and biomedicine. The novelty of the present work is the fabrication of ZnFe2O4/RGO NCs by using a one-step hydrothermal process to assess the influence of RGO doping on the physicochemical properties and anticancer efficacy of ZnFe2O4 NPs. X-ray diffraction (XRD), Scanning electron microscopy (SEM), Energy-dispersive X-ray(EDX), X-ray photoelectron spectroscopy (XPS), Fourier-transform infrared spectroscopy (FTIR), UV-vis spectroscopy, and Photoluminescence (PL) spectroscopy were employed to characterize prepared pure ZnFe2O4 NPs and ZnFe2O4/ RGO NCs. XRD results showed that the synthesized samples have high crystallinity. Furthermore, the average crystal sizes of ZnFe2O4 nanoparticles (NPs) and ZnFe2O4/RGO nanocomposites (NCs) were 51.08 nm and 54.36 nm, respectively. SEM images revealed that pure ZnFe2O4 NPs were spherical in shape with uniformly loaded on the surface of the RGO nanosheet. XPS and EDX analysis confirmed the elemental compositions of ZnFe2O4/RGO NCs. Elemental mapping of SEM shows that the elemental compositions (Zn, Fe, O, and C) were homogeneously distributed in ZnFe2O4/RGO NCs. The intensity of FT-IR spectra depicted that pure ZnFe2O4 NPs were successfully anchored into the RGO nanosheet. An optical study suggested that the band gap energy of ZnFe2O4/RGO NCs (1.61 eV) was lower than that of pure ZnFe2O4 NPs (1.96 eV). PL spectra indicated that the recombination rate of the ZnFe2O4/ RGO NCs was lower than ZnFe2O4 NPs. MTT assay was used to evaluate the anticancer performance of ZnFe2O4 /RGO NCs and pure ZnFe2O4NPs against human cancer cells. In vitro study indicates that ZnFe2O4 /RGO NCs have higher anticancer activity against human breast (MCF-7) and lung (A549) cancer cells as compared to pure form ZnFe2O4 NPs. This work suggests that RGO doping enhances the anticancer activity of ZnFe2O4NPs by tuning its optical behavior. This study warrants future research on potential therapeutic applications of these types of nanocomposites.

Bi2O3-Doped WO3 Nanoparticles Decorated on rGO Sheets: Simple Synthesis, Characterization, Photocatalytic Performance, and Selective Cytotoxicity toward Human Cancer Cells.

Graphene derivatives and metal oxide-based nanocomposites (NCs) are being studied for their diverse applications including gas sensing, environmental remediation, and biomedicine. The aim of the present work was to evaluate the effect of rGO and Bi2O3 integration on photocatalytic and anticancer efficacy. A novel Bi2O3-WO3/rGO NCs was successfully prepared via the precipitation method. X-ray crystallography (XRD) data confirmed the crystallographic structure and the phase composition of the prepared samples. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analysis confirmed the loading of Bi2O3-doped WO3 NPs on rGO sheets. Energy-dispersive X-ray (EDX) results confirmed that all elements of carbon (C), oxygen (O), tungsten (W), and bismuth (Bi) were present in Bi2O3-WO3/rGO NCs. The oxidation state and presence of elemental compositions in Bi2O3-WO3/rGO NCs were verified by the X-ray photoelectron spectroscopy (XPS) study. Raman spectra indicate a reduction in carbon-oxygen functional groups and an increase in the graphitic carbon percentage of the Bi2O3-WO3/rGO NCs. The functional group present in the prepared samples was examined by Fourier transform infrared (FTIR) spectroscopy. UV analysis showed that the band gap energy of the synthesized samples was slightly decreased with Bi2O3 and rGO doping. Photoluminescence (PL) spectra showed that the recombination rate of the electron-hole pair decreased with the dopants. Degradation of RhB dye under UV light was employed to evaluate photocatalytic performance. The results showed that the Bi2O3-WO3/rGO NCs have high photocatalytic activity with a degradation rate of up to 91%. Cytotoxicity studies showed that Bi2O3 and rGO addition enhance the anticancer activity of WO3 against human lung cancer cells (A549) and colorectal cancer cells (HCT116). Moreover, Bi2O3-WO3/rGO NCs showed improved biocompatibility in human umbilical vein endothelial cells (HUVECs) than pure WO3 NPs. The results of this work showed that Bi2O3-doped WO3 particles decorated on rGO sheets display improved photocatalytic and anticancer activity. The preliminary data warrants further research on such NCs for their applications in the environment and medicine.

Photocatalytic Degradation of Methylene Blue and Anticancer Response of In2O3/RGO Nanocomposites Prepared by a Microwave-Assisted Hydrothermal Synthesis Process.

The incorporation of graphene with metal oxide has been widely explored in various fields, including energy storage devices, optical applications, biomedical applications, and water remediation. This research aimed to assess the impact of reduced graphene oxide (RGO) doping on the photocatalytic and anticancer properties of In2O3 nanoparticles. Pure and In2O3/RGO nanocomposites were effectively synthesized using the single-step microwave hydrothermal process. XRD, TEM, SEM, EDX, XPS, Raman, UV-Vis, and PL spectroscopy were carefully utilized to characterize the prepared samples. XRD data showed that synthesized In2O3 nanoparticles had high crystallinity with a decreased crystal size after RGO doping. TEM and SEM images revealed that the In2O3 NPs were spherical and uniformly embedded onto the surface of RGO sheets. Elemental analysis of In2O3/RGO NC confirmed the presence of In, O, and C without impurities. Raman analysis indicated the successful fabrication of In2O3 onto the RGO surface. Uv-Vis analysis showed that the band gap energy was changed with RGO addition. Raman spectra confirmed that In2O3 nanoparticles were successfully anchored onto the RGO sheet. PL results indicated that the prepared In2O3/RGO NCs can be applied to enhance photocatalytic activity and biomedical applications. In the degradation experiment, In2O3/RGO NCs exhibited superior photocatalytic activity compared to that of pure In2O3. The degradation efficiency of In2O3/RGO NCs for MB dye was up to 90%. Biological data revealed that the cytotoxicity effect of In2O3/RGO NCs was higher than In2O3 NPs in human colorectal (HCT116) and liver (HepG2) cancer cells. Importantly, the In2O3/RGO NCs exhibited better biocompatibility against human normal peripheral blood mononuclear cells (PBMCs). All the results suggest that RGO addition improves the photocatalytic and anticancer activity of In2O3 NPs. This study highlights the potential of In2O3/RGO NCs as an efficient photocatalyst and therapeutic material for water remediation and biomedicine.

An integrative GC-MS and LC-MS metabolomics platform determination of the metabolite profile of Bombax ceiba L. root, and in silico & in vitro evaluation of its antibacterial & antidiabetic activities.

The Bombax ceiba L. tree is a member of the family Bombacaceae and the genus Bombax. Both Chinese and Indian traditional medicine have made extensive use of it in the treatment of sickness. Its chemical composition is still a mystery. B. ceiba roots methanol extract (BCRME) was analyzed by different chromatographic analytical techniques in order to identify its major chemical constituents. Twelve compounds and six compounds were identified from GC-MS and LC-MS analysis, respectively. This is the first report on the presence of lathodoratin, cedrene, 4H-1-benzopyran-4-one,8-[{dimethylamino} methyl]-7-methoxy-3-methyl-2-phenyl, asiatic acid, and (E)-2,4,4'-trihydroxylchalcone in B. ceiba roots. Methanol extract demonstrated noteworthy antibacterial activity against Staphylococcus aureus (MTCC96) (MIC: 100 µg/mL) compare to antibiotic ampicillin (MIC: 250 µg/mL) as well as the highest α-amylase inhibition (IC50=26.91 µg/mL) and α-glucosidase inhibition (IC50=21.21 µg/mL) effects, molecular docking study confirmed these findings, with some compounds having a very high docking score.

Photodeposition mediated synthesis of silver-doped indium oxide nanoparticles for improved photocatalytic and anticancer performance.

Indium oxide nanoparticles (In2O3 NPs) are being investigated for a number of applications including gas-sensing, environmental remediation, and biomedicine. We aimed to examine the effect of silver (Ag) doping on photocatalytic and anticancer activity of In2O3 NPs. The Ag-doped (2%, 4%, and 6%weight) In2O3 NPs were synthesized by the photodeposition method. Prepared samples were characterized via X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FTIR), UV-Vis spectroscopy, and the photoluminescence (PL). XRD data showed that Ag-doping increases the crystallinity of In2O3 NPs. SEM and TEM images indicated that In2O3 NPs have spherical morphology with smooth surfaces, and Ag-doping increases the size without affecting the particle's shape. XPS spectra showed the oxidation state and the presence of Ag in In2O3 NPs. Band gap energy of In2O3 NPs decreases with increasing the concentration of Ag (3.41 eV to 3.12 eV). The peak intensity of PL spectra of In2O3 NPs also reduces with the increment of Ag ions suggesting the hindrance of the recombination rate of e-/h+. The photocatalytic activity was measured by the degradation of Rh B dye under UV irradiation. The degradation efficiency of Ag-doped (6%) In2O3 NPs was 92%. Biochemical data indicated that Ag-doping enhances the anticancer performance of In2O3 NPs against human lung cancer cells (A549). Moreover, Ag-doped In2O3 NPs displayed excellent biocompatibility in normal human lung fibroblasts (IMR90). Overall, this study demonstrated that Ag-doping enhances the photocatalytic activity and anticancer efficacy of In2O3 NPs. This study warrants further investigation on the environmental and biomedical applications of Ag-In2O3 NPs.

Synthesis of Trimetallic (Ni-Cu)@Ag Core@Shell Nanoparticles without Stabilizing Materials for Antibacterial Applications.

We report a simple method to prepare colloidal trimetallic (Ni-Cu)@Ag core@shell nanoparticles (NPs) without stabilizing materials. Experimental evidence was found for the successful synthesis of these NPs using X-ray diffraction (XRD), optical spectroscopy, and high-resolution transmission electron microscopy (HRTEM). The presence of core metals (Ni and Cu) was confirmed by elemental analysis using a total reflection X-ray fluorescence (TXRF) analysis. In addition, the absorption spectra of the prepared samples exhibited broad bands compared to the bands of the monometallic NPs, indicating the formation of a core-shell nanostructure. The antibacterial activity of the trimetallic NPs was evaluated against three Gram-negative (Pseudomonas aeruginosa, Escherichia coli, and Salmonella) and two Gram-positive (Streptococcus and Staphylococcus aureus) bacteria on Mueller-Hinton agar. These NPs showed high inhibition of bacterial growth at the low sample concentrations used in this study compared to other nanomaterials. One of the interesting results of the current study is that the inhibition zone of Pseudomonas aeruginosa as a resistant bacterium was high for most NPs. These results make the prepared samples promising candidates for antibiotic material applications.

High Performance of Carbon Monoxide Gas Sensor Based on a Novel PEDOT:PSS/PPA Nanocomposite.

In this work, the carbon monoxide (CO) detection property of poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate)/poly(p-anisidine) (PEDOT:PSS/PPA) nanocomposite was systematically investigated at room temperature. The PEDOT:PSS/PPA nanocomposite was synthesized by the cost-effective "in situ chemical oxidation polymerization" technique. The electric, optical, spectroscopic, and structural properties of the as-prepared nanomaterials were analyzed with I-V, UV-vis, Raman, Fourier transform infrared (FTIR), and X-ray diffraction (XRD) spectroscopies. Topological investigations of materials were conducted by atomic force microscopy (AFM). The gas-sensing performance of the PEDOT:PSS/PPA and PEDOT:PSS nanocomposites toward CO gas in the concentration range of 50-300 ppm at room temperature was explored, and their performances were compared. The PEDOT:PSS/PPA sensor shows a perfectly linear response to different concentrations (50-300 ppm) of CO gas (R 2 = 0.9885), and the response time and recovery time of the CO gas sensor (100 ppm) can be about 58 and 61 s, respectively, showing high sensitivity to CO gas and rapid response recovery with outstanding stability. Thus, the PEDOT:PSS/PPA-based sensors, with their impressive sensing performance, may give assurance for future high-performance CO-sensing applications.

Design and synthesis of novel enantiopure Bis(5-Isoxazolidine) derivatives: insights into their antioxidant and antimicrobial potential via in silico drug-likeness, pharmacokinetic, medicinal chemistry properties, and molecular docking studies.

A series of novel compounds, mono-5-isoxazolidines, and bis (5-isoxazolidines) derivatives, were prepared as bicycloadducts. The new series of isoxazolidines were designed and synthesized via 1,3-dipolar cycloaddition reaction of nitrones with 3,9-Divinyl-2,4,8,10-tetra oxaspiro (5-5) undecane in the context of new antimicrobial and antioxidant drugs discovery and were fully characterized by FT-IR, 13C-NMR, and 1H-NMR spectroscopy. The physicochemical properties of all the novel cycloadducts, like bioactivity score and lipophilicity, were predicted using calculative methods. Similarly, the pharmacokinetic properties such as metabolism, absorption, distribution, and excretion (ADME) were also predicted. Most of the tested compounds exhibited antimicrobial properties to varying degrees against various bacterial species, including the Gram-negative bacteria Pseudomonas aeruginosa and Escherichia coli, and the Gram-positive bacteria Streptococcus pyogenus and Staphylococcus aureus, Antifungal properties were also observed against the tested fungi like Candida albicans, Aspergillus niger, and Aspergillus clavatus. The activity data exhibited that most compounds have high activity as compared to the standard drugs. In the range of graded doses, the results of some selected compounds revealed that some are high antioxidants while others are moderate or weak antioxidants. As evidenced by the molecular docking studies, the synthesized compounds showed good binding mode better than a standard drug, against the protein of a Pantothenate Synthetase enzyme (PDB-2X3F).

One-Pot Synthesis of SnO2-rGO Nanocomposite for Enhanced Photocatalytic and Anticancer Activity.

Metal oxide and graphene derivative-based nanocomposites (NCs) are attractive to the fields of environmental remediation, optics, and cancer therapy owing to their remarkable physicochemical characteristics. There is limited information on the environmental and biomedical applications of tin oxide-reduced graphene oxide nanocomposites (SnO2-rGO NCs). The goal of this work was to explore the photocatalytic activity and anticancer efficacy of SnO2-rGO NCs. Pure SnO2 NPs and SnO2-rGO NCs were prepared using the one-pot hydrothermal method. X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FTIR), UV-Vis spectrometry, photoluminescence (PL), and Raman scattering microscopy were applied to characterize the synthesized samples. The crystallite size of the SnO2 NPs slightly increased after rGO doping. TEM and SEM images show that the SnO2 NPs were tightly anchored onto the rGO sheets. The XPS and EDX data confirmed the chemical state and elemental composition of the SnO2-rGO NCs. Optical data suggest that the bandgap energy of the SnO2-rGO NCs was slightly lower than for the pure SnO2 NPs. In comparison to pure SnO2 NPs, the intensity of the PL spectra of the SnO2-rGO NCs was lower, indicating the decrement of the recombination rate of the surfaces charges (e-/h+) after rGO doping. Hence, the degradation efficiency of methylene blue (MB) dye by SnO2-rGO NCs (93%) was almost 2-fold higher than for pure SnO2 NPs (54%). The anticancer efficacy of SnO2-rGO NCs was also almost 1.5-fold higher against human liver cancer (HepG2) and human lung cancer (A549) cells compared to the SnO2 NPs. This study suggests a unique method to improve the photocatalytic activity and anticancer efficacy of SnO2 NPs by fusion with graphene derivatives.

Facile Synthesis, Characterization, Photocatalytic Activity, and Cytotoxicity of Ag-Doped MgO Nanoparticles.

Due to unique physicochemical properties, magnesium oxide nanoparticles (MgO NPs) have shown great potential for various applications, including biomedical and environmental remediation. Moreover, the physiochemical properties of MgO NPs can be tailored by metal ion doping that can be utilized in photocatalytic performance and in the biomedical field. There is limited study on the photocatalytic activity and biocompatibility of silver (Ag)-doped MgO NPs. This study was planned for facile synthesis, characterization, and photocatalytic activity of pure and silver (Ag)-doped MgO NPs. In addition, cytotoxicity of pure and Ag-doped MgO NPs was assessed in human normal umbilical vein endothelial cells (HUVECs). Pure MgO NPs and Ag-doped (1, 2, 5, and 7.5 mol%) MgO NPs were prepared via a simple sol-gel procedure. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FTIR), photoluminescence (PL), and X-ray photoelectron spectroscopy (XPS) were used to characterize the prepared samples. XRD results showed the preparation of highly crystalline NPs with no impurity peaks. TEM and SEM studies indicate smooth surfaces with almost spherical morphology of MgO NPs, and Ag-doping did not change the morphology. Elemental composition study suggested that Ag is uniformly distributed in MgO particles. Intensity of the PL spectra of MgO NPs decreased with increasing the concentration of Ag dopants. In comparison to pure MgO NPs, Ag-MgO NPs showed higher degradation of methylene blue (MB) dye under UV irradiation. The improved photocatalytic activity of Ag-MgO NPs was related to the effect of dopant concentration on reducing the recombination between electrons and holes. Cytotoxicity studies showed good biocompatibility of pure and Ag-doped MgO NPs with human normal umbilical vein endothelial cells (HUVECs). These results highlighted the potential of Ag-doped MgO NPs in environmental remediation.

Facile Synthesis of Zn-Doped Bi2O3 Nanoparticles and Their Selective Cytotoxicity toward Cancer Cells.

Bismuth (III) oxide nanoparticles (Bi2O3 NPs) have shown great potential for biomedical applications because of their tunable physicochemical properties. In this work, pure and Zn-doped (1 and 3 mol %) Bi2O3 NPs were synthesized by a facile chemical route and their cytotoxicity was examined in cancer cells and normal cells. The X-ray diffraction results show that the tetragonal phase of ß-Bi2O3 remains unchanged after Zn-doping. Transmission electron microscopy and scanning electron microscopy images depicted that prepared particles were spherical with smooth surfaces and the homogeneous distribution of Zn in Bi2O3 with high-quality lattice fringes without distortion. Photoluminescence spectra revealed that intensity of Bi2O3 NPs decreases with increasing level of Zn-doping. Biological data showed that Zn-doped Bi2O3 NPs induce higher cytotoxicity to human lung (A549) and liver (HepG2) cancer cells as compared to pure Bi2O3 NPs, and cytotoxic intensity increases with increasing concentration of Zn-doping. Mechanistic data indicated that Zn-doped Bi2O3 NPs induce cytotoxicity in both types of cancer cells through the generation of reactive oxygen species and caspase-3 activation. On the other hand, biocompatibility of Zn-doped Bi2O3 NPs in normal cells (primary rat hepatocytes) was greater than that of pure Bi2O3 NPs and biocompatibility improves with increasing level of Zn-doping. Altogether, this is the first report highlighting the role of Zn-doping in the anticancer activity of Bi2O3 NPs. This study warrants further research on the antitumor activity of Zn-doped Bi2O3 NPs in suitable in vivo models.

High Surface Reactivity and Biocompatibility of Y2O3 NPs in Human MCF-7 Epithelial and HT-1080 FibroBlast Cells.

This study aimed to generate a comparative data on biological response of yttrium oxide nanoparticles (Y2O3 NPs) with the antioxidant CeO2 NPs and pro-oxidant ZnO NPs. Sizes of Y2O3 NPs were found to be in the range of 35±10 nm as measured by TEM and were larger from its hydrodynamic sizes in water (1004 ± 134 nm), PBS (3373 ± 249 nm), serum free culture media (1735 ± 305 nm) and complete culture media (542 ± 108 nm). Surface reactivity of Y2O3 NPs with bovine serum albumin (BSA) was found significantly higher than for CeO2 and ZnO NPs. The displacement studies clearly suggested that adsorption to either BSA, filtered serum or serum free media was quite stable, and was dependent on whichever component interacted first with the Y2O3 NPs. Enzyme mimetic activity, like that of CeO2 NPs, was not detected for the NPs of Y2O3 or ZnO. Cell viability measured by MTT and neutral red uptake (NRU) assays suggested Y2O3 NPs were not toxic in human breast carcinoma MCF-7 and fibroblast HT-1080 cells up to the concentration of 200 µg/mL for a 24 h treatment period. Oxidative stress markers suggested Y2O3 NPs to be tolerably non-oxidative and biocompatible. Moreover, mitochondrial potential determined by JC-1 as well as lysosomal activity determined by lysotracker (LTR) remained un-affected and intact due to Y2O3 and CeO2 NPs whereas, as expected, were significantly induced by ZnO NPs. Hoechst-PI dual staining clearly suggested apoptotic potential of only ZnO NPs. With high surface reactivity and biocompatibility, NPs of Y2O3 could be a promising agent in the field of nanomedicine.

TiO2 nanoparticles potentiated the cytotoxicity, oxidative stress and apoptosis response of cadmium in two different human cells.

Widespread application of titanium dioxide nanoparticles (nTiO2) and ubiquitous cadmium (Cd) pollution may increase their chance of co-existence in the natural environment. Toxicological information on co-exposure of nTiO2 and Cd in mammalian models is largely lacking. Hence, we studied the combined effects of nTiO2 and Cd in human liver (HepG2) and breast cancer (MCF-7) cells. We observed that nTiO2 did not produce toxicity to HepG2 and MCF-7 cells. However, moderate concentration of Cd exposure caused cytotoxicity to both cells. Interestingly, non-cytotoxic concentration of nTiO2 effectively enhanced the oxidative stress response of Cd indicated by pro-oxidants generation (reactive oxygen species, hydrogen peroxide, and lipid peroxidation) and antioxidants depletion (glutathione level and glutathione reductase, superoxide dismutase, and catalase enzymes). Moreover, nTiO2 potentiated the Cd-induced apoptosis in both cells suggested by altered expression of p53, bax, and bcl-2 genes along with low mitochondrial membrane potential. Cellular uptake results demonstrated that nTiO2 facilitates the internalization of Cd into the cells. Overall, this study demonstrated that non-cytotoxic concentration of nTiO2 enhanced the toxicological potential of Cd in human cells. Therefore, more attention should be paid on the combine effects of nTiO2 and Cd on human health.

Evaluation of the Cytotoxicity and Oxidative Stress Response of CeO2-RGO Nanocomposites in Human Lung Epithelial A549 Cells.

Graphene-based nanocomposites have attracted enormous interest in nanomedicine and environmental remediation, owing to their unique characteristics. The increased production and widespread application of these nanocomposites might raise concern about their adverse health effects. In this study, for the first time, we examine the cytotoxicity and oxidative stress response of a relatively new nanocomposite of cerium oxide-reduced graphene oxide (CeO2-RGO) in human lung epithelial (A549) cells. CeO2-RGO nanocomposites and RGO were prepared by a simple hydrothermal method and characterized by relevant analytical techniques. Cytotoxicity data have shown that RGO significantly induces toxicity in A549 cells, evident by cell viability reduction, membrane damage, cell cycle arrest, and mitochondrial membrane potential loss. However, CeO2-RGO nanocomposites did not cause statistically significant toxicity as compared to a control. We further observed that RGO significantly induces reactive oxygen species generation and reduces glutathione levels. However, CeO2-RGO nanocomposites did not induce oxidative stress in A549 cells. Interestingly, we observed that CeO2 nanoparticles (NPs) alone significantly increase glutathione (GSH) levels in A549 cells as compared to a control. The GSH replenishing potential of CeO2 nanoparticles could be one of the possible reasons for the biocompatible nature of CeO2-RGO nanocomposites. Our data warrant further and more advanced research to explore the biocompatibility/safety mechanisms of CeO2-RGO nanocomposites in different cell lines and animal models.