Hydrothermal synthesis of CdIn2S4 nanostructures using new starting reagent for elevating solar cells efficiency

Bioinspired silk fibroin nano-delivery systems protect against 5-FU induced gastrointestinal mucositis in a mouse model and display antitumor effects on HT-29 colorectal cancer cells in vitro

Colorectal cancer (CRC), is the second cause of cancer-related deaths worldwide is one of the most prevalent types of cancers. Conventional treatment continues to rely on surgery, chemotherapy, and radiotherapy, but for advanced cases, adjuvant chemotherapy remains the main approach for improving surgical outcomes and lower the disease recurrence probability. Chemotherapy-induced gastrointestinal (GI) toxicity is the main dose-limiting factor for many chemotherapeutic regimens, including 5-FU, and one of the biggest oncological challenges. Up to 40% of the patients receiving 5-FU get mucositis, 10-15% of which develop severe symptoms. In this context, our study aimed to develop a bioinspired nanosized drug delivery system as a strategy to reduce 5-FU associated side effects, such as GI mucositis. To this end, SF-based nanoparticles were prepared and characterized in terms of size and morphology, as well as in terms of in vitro antitumoral activity on a biomimetic colorectal cancer model by investigation of apoptosis, DNA fragmentation, and release of reactive oxygen species. Additionally, the capacity of the SF-based nanocarriers to offer intestinal protection against 5-FU-induced GI mucositis was evaluated in vivo using a mouse model that mimics the chemotherapy-associated gut mucositis occurring in colorectal cancer. Our studies show that silk fibroin nanoparticles efficiently deliver 5-FU to tumor cells in vitro while protecting against drug-induced GI mucositis in a mouse model.

Autophagy: A Promising Target for Age-related Osteoporosis

Autophagy is a process the primary role of which is to clear up damaged cellular components such as long-lived proteins and organelles, thus participating in the conservation of different cells. Osteoporosis associated with aging is characterized by consistent changes in bone metabolism with suppression of bone formation as well as increased bone resorption. In advanced age, not only bone mass but also bone strength decrease in both sexes, resulting in an increased incidence of fractures. Clinical and animal experiments reveal that age-related bone loss is associated with many factors such as accumulation of autophagy, increased levels of reactive oxygen species, sex hormone deficiency, and high levels of endogenous glucocorticoids. Available basic and clinical studies indicate that age-associated factors can regulate autophagy. Those factors play important roles in bone remodeling and contribute to decreased bone mass and bone strength with aging. In this review, we summarize the mechanisms involved in bone metabolism related to aging and autophagy, supplying a theory for therapeutic targets to rescue bone mass and bone strength in older people.

Ultrasonic-assisted synthesis and DNA interaction studies of two new Ru complexes; RuO2 nanoparticles preparation

AIM

To study of the interactions of two new ruthenium(II) complexes (C1 and C2) with calf thymus (CT)-DNA; production of RuO₂ nanoparticles using the complexes precursor.

MATERIALS & METHODS

Complex C1 was characterized by x-ray crystallography. The binding of the complexes with (CT)-DNA was studied using techniques that include electronic absorption spectra, fluorescence and redox behavior. The preparation of RuO₂ nanoparticles was carried out by thermal decomposition.

RESULTS

The interaction mode of DNA with complexes is the type of electrostatic. It was revealed that sonication of the samples, before thermal decomposition, has been affected the morphologies and sizes of the resulting nanoparticles.

CONCLUSION

The complexes are capable of interaction with DNA molecules and they have a good potential to prepare nanostructures.

Influence of CdS Morphology on the Efficiency of Dye-Sensitized Solar Cells

Cadmium sulfide (CdS) used in dye-sensitized solar cells (DSSCs) is currently mainly synthesized by chemical bath deposition, vacuum evaporation, spray deposition, chemical vapor deposition, electrochemical deposition, sol-gel, solvothermal, radio frequency sputtering, and hydrothermal process. In this paper, CdS was synthesized by hydrothermal process and used with a mixture of titanium dioxide anatase and rutile (TiO2(A+R)) to build the photoanode, whereas the counter electrode was made of nanocomposites of conductive polymer polyaniline (PANI) and multiwalled carbon nanotubes (MWCNTs) deposited on a fluorine-doped tin oxide substrate. Two morphologies of CdS have been obtained by using hydrothermal process: branched nanorods (CdSBR) and straight nanorods (CdSNR). The present work indicates that controlling the morphology of CdS is crucial to enhance the efficiency of DSSCs device. Indeed, the higher power conversion energy of 1.71% was achieved for a cell CdSBR-TiO2(A+R)/PANI-MWCNTs under 100 mW/cm2, whereas the power conversion energy of 0.97 and 0.83% for CdSNR-TiO2(A+R)/PANI-MWCNTs and TiO2(A+R)/PANI-MWCNTs, respectively. Therefore, by increasing the surface to volume ratio of CdS nanostructures and the crystallite size into those structures opens the way to low-cost chemical production of solar cells.

Nanopowder synthesis of novel Sn(II)-imprinted poly(dimethyl vinylphosphonate) by ultrasound-assisted technique: Adsorption and pre-concentration of Sn(II) from aqueous media and real samples

In this research, a novel Sn(II)-imprinted poly(dimethyl vinylphosphonate) nanopowder (Sn(II)-IPDMVPN) was prepared using Sn²⁺, dimethyl vinylphosphonate, azobis isobutyronitril and ethylene glycol dimethacrylate as the template, ligand, initiator and cross linker, respectively. The non-imprinted poly(dimethyl vinylphosphonate) nanopowder (NIPDMVPN) was also synthesized utilizing the same procedure without using SnCl₂·2H₂O in order to compare the results with the Sn(II)-IPDMVPN. The structure, morphology and composition of the products were characterized by XRD, SEM, EDX, XRF, BET, FT-IR and NMR techniques. Some experimental conditions including pH, eluent concentration and sample volume were optimized to maximize Sn(II) adsorption by the Sn(II)-IPDMVPN. It was found that the optimum conditions are pH = 5, 1.00 M of HNO₃ as eluent and sample volume up to 50 mL. The results obtained by ICP-MS indicated that the Sn(II)-IPDMVPN had much higher adsorption capacity for Sn(II) ions (about threefold) than the NIPDMVPN. The applicability of the Sn(II)-IPDMVPN was also investigated in three different real samples. Under the best experimental conditions, the calibration graphs were linear in the range of 0.19-90 μg L^-1 with a coefficient of determination (R²) of 0.990. The detection limit was calculated to be 0.06 μg L^-1. The relative standard deviation (RSD) for six replicate measurements of Sn(II) at 1.00 ng mL^-1 was determined to be 1.8%. The results showed that the Sn(II)-IPDMVPN-ICP-MS is a very simple, rapid, sensitive and efficient method for the determination of Sn(II) ions in water samples.

Sonochemical synthesis of two novel Pb(II) 2D metal coordination polymer complexes: New precursor for facile fabrication of lead(II) oxide/bromide micro-nanostructures

Two new lead(II) coordination polymer complexes (CSCs) (2D), [Pb₂(L)₂(Br)₂]_n·H₂O (1), [Pb₂(HL^/)(L^/)(H₂O)₂]_n·H₂O (2), where L = C₆H₅NO₂ (2-pyridinecarboxylic acid) and L^/ = C₉H₆O₆ (1,3,5-tricarboxylic acid), have been synthesized under different experimental conditions. Micrometric crystals (bulk) or microsized materials have been obtained depending on using the branch tube method or sonochemical irradiation. All materials have been characterized by scanning electron microscopy (SEM), powder X-ray diffraction (PXRD) and FT-IR spectroscopy. Single crystal X-ray analyses on complexes 1 and 2 shows that Pb²⁺ ions are 8-coordinated, 7 and 9-coordinated, respectively. Topological analysis shows that the compound 1 and 2 are 4,6L26 and bnn net, respectively. However, neither the shape nor the morphology is maintained, showing the role of sonochemistry to modulate both morphology and dimensions of the resulting crystalline material, independently of whether we have a 2D coordination polymer (CP). Finally, micro structuration of lead(II) bromide oxide and lead(II) oxide have been prepared by calcination of two different lead (II) CPs at 700 °C that were characterized by SEM and XRD.

The effects of solvent and ultrasonic irradiation in synthesis of thallium(I) nano supramolecular polymers and use them as template for synthesis of thallium(III) oxide nanostructures with desirable morphology

In order to study the effects of solvent and ultrasonic irradiation on formation of [Tl(HTar)]_n (1) and/or [Tl₂(Tar)]_n (2), [H₂Tar = (+)-tartaric acid] supramolecular polymers, we designed some experiments and synthesized four samples of 1 under the reaction of H₂Tar and TlNO₃ by sonochemical process and as the bulk samples. Nanostructures of compounds 1 and 2 as the bulk samples could be synthesized without ultrasonic irradiation, too. In the presence of ultrasonic waves, with acetonitrile solvent, more discrete nanoparticles were obtained. These four samples have been used as new precursors for preparation of thallium(III) oxide nanostructures via solid-state thermal decomposition process. There is a direct relationship between the morphology of initial precursors and resulting thallium(III) oxide nanostructures. These nanostructures were characterized by IR spectroscopy, X-ray powder diffraction (XRD) and Scanning Electron Microscopy (SEM).

Nanocomposite materials based on poly(vinyl chloride) and bovine serum albumin modified ZnO through ultrasonic irradiation as a green technique: Optical, thermal, mechanical and morphological properties

In this project, physicochemical properties of poly(vinyl chloride) (PVC) reinforced by ZnO nanoparticles (NPs) were studied. Firstly, ZnO NPs were modified with bovine serum albumin (BSA) as an organo-modifier and biocompatible substance through ultrasound irradiation as environmental friendly, low cost and rapid means. Nanocomposite (NC) films were prepared by loadings of various ratios of ZnO/BSA NPs (3, 6 and 9wt%) inside the PVC. Structural morphology and physical properties of the ZnO-BSA NPs and NC films were investigated via Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis (TGA), transmission electron microscopy and field emission scanning electron microscopy. According to the obtained information from the TGA, an increase in the thermal stability can be clearly observed. Also the results of contact angle analysis indicated with increasing percent of ZnO/BSA NPs into PVC the hydrophilic behaviors of NCs were increased.

Photovoltaic Performance of Vapor-Assisted Solution-Processed Layer Polymorph of Cs3Sb2I9

The presence of toxic lead (Pb) remains a major obstruction to the commercial application of perovskite solar cells. Although antimony (Sb)-based perovskite-like structures A₃M₂X₉ can display potentially useful photovoltaic behavior, solution-processed Sb-based perovskite-like structures usually favor the dimer phase, which has poor photovoltaic properties. In this study, we prepared a layered polymorph of Cs₃Sb₂I₉ through solution-processing and studied its photovoltaic properties. The exciton binding energy and exciton lifetime of the layer-form Cs₃Sb₂I₉ were approximately 100 meV and 6 ns, respectively. The photovoltaic properties of the layered polymorph were superior to those of the dimer polymorph. A solar cell incorporating the layer-form Cs₃Sb₂I₉ exhibited an open-circuit voltage of 0.72 V and a power conversion efficiency of 1.5%-the highest reported for an all-inorganic Sb-based perovskite.