Effective Adsorption and Removal of Doxorubicin from Aqueous Solutions Using Mesostructured Silica Nanospheres: Box-Behnken Design Optimization and Adsorption Performance Evaluation.

The aim of this study is to evaluate the efficacy of mesoporous silica nanospheres as an adsorbent to remove doxorubicin (DOX) from aqueous solution. The surface and structural properties of mesoporous silica nanospheres were investigated using BET, SEM, XRD, TEM, ζ potential, and point of zero charge analysis. To optimize DOX removal from aqueous solution, a Box-Behnken surface statistical design (BBD) with four times factors, four levels, and response surface modeling (RSM) was used. A high amount of adsorptivity from DOX (804.84 mg/g) was successfully done under the following conditions: mesoporous silica nanospheres dose = 0.02 g/25 mL; pH = 6; shaking speed = 200 rpm; and adsorption time = 100 min. The study of isotherms demonstrated how well the Langmuir equation and the experimental data matched. According to thermodynamic characteristics, the adsorption of DOX on mesoporous silica nanospheres was endothermic and spontaneous. The increase in solution temperature also aided in the removal of DOX. The kinetic study showed that the model suited the pseudo-second-order. The suggested adsorption method could recycle mesoporous silica nanospheres five times, with a modest reduction in its ability for adsorption. The most important feature of our adsorbent is that it can be recycled five times without losing its efficiency.

A promising 1D Cd-based hybrid perovskite-type for white-light emission with high-color-rendering index.

A one dimensional (1D) perovskite-type (C6H7NBr)3[CdBr5] (abbreviated 4-BAPC) was synthesized by slow evaporation at room temperature (RT). 4-BAPC crystalizes in the monoclinic system with the space group P21/c. The 1D inorganic chains are formed by corner sharing CdBr6 octahedra. Thermal measurement shows that 4-BAPC is stable up to 190 °C. Optical characterization demonstrates that the grown crystal is an indirect bandgap material with a bandgap value of 3.93 eV, which is consistent with theoretical calculations. The electronic structure, calculated using density functional theory, reveals that the valence band originates from a combination of Br-4p orbitals and Cd-4d orbitals, whereas the conduction band originates from the Cd-5s orbitals. The photoluminescence spectroscopy shows that the obtained material exhibits a broad-band white light emission with extra-high CRI of 98 under λ exc = 380 nm. This emission is mainly resulting from the self-trapped exciton recombinations within the inorganic CdBr6 octahedron, and the fluorescence within the organic conjugated ammonium salt.

Composition and Characterization of Cold Pressed Moringa oleifera Seed Oil.

The present study aims to investigate the volatile compound and the triacylglycerol profiles of Tunisian cold pressed Moringa oleifera seed oil (MoSO) and to assess its thermal properties and its biological activities. GC-MS analysis identified thirty six phyto-compounds amounting to 98.99% of the total oil. These compounds were classified into eleven groups among which the fatty acid one exhibited the highest intensity (91.63%). Cis, 6-octadecenoic acid was the most abundant compound (70.68%). The triacylglycerol composition of MoSO was characterized by the predominance of the glycerol trioleate (OOO) (32.42±0.12%). Thermogravimetric analysis of MoSO showed that the oil possess an interesting thermal stability with a highly Onset temperatures (Tonset) of 390.72°C and 357.47°C, respectively in nitrogen and air atmospheres. By using the ABTS assay, MoSO exhibited an interesting antioxidant capacity of 365 µM TEAC. The oil was also endowed with a relatively strong anti-inflammatory activity since its treatment at the different concentrations tested (75, 150 and 300 µg/mL). However, no antimicrobial activity was observed. On the basis of the obtained results, MoSO could be used in diverse industrial applications such as pharmaceutical, cosmetic, and food fields thanks to its thermal stability and interesting biological activities.

Viscoelastic and dielectric properties of 5CB nematic liquid crystal doped by magnetic and nonmagnetic nanoparticles.

In this article we show how spherical nanoparticles (NPs) imposing planar anchoring can strongly impact the viscoelastic, dielectric, and electro-optical properties of a nematic liquid crystal when they are not aggregated. We also demonstrate that when the NPs are magnetic, most nematic properties are more impacted than when they are nonmagnetic. With magnetic NPs a molecular disorder is induced that decreases the nematic order parameter, this decrease impacting the values of elastic constants, viscosity, and response time. The impact on 5CB liquid crystal (LC) has been investigated with spherical nanoparticles (NPs) of identical size around 6 nm, magnetic (γFe_{2}O_{3}), and nonmagnetic (CeO_{2}) ones that are both surface functionalized by poly(aminopropylmethylsiloxane-b-dimethylsiloxane) (PAPMS-b-PDMS) block copolymer ligands to promote planar anchoring. In the presence of nonmagnetic NPs, despite an almost constant nematic order parameter, a significant decrease of elastic constants (25.4%), viscosity (22%), and response time (23%) is measured. It suggests a dilution effect for the intermolecular interactions in the presence of NPs. This hypothesis is supported by the observation of an enhanced decrease of the same nematic parameters in the presence of magnetic NPs that can be fully explained by the corresponding order parameter decrease. This finally leads to a remarkable decrease of the splay elastic constant by 51% in the presence of magnetic NPs. The decrease of the nematic order parameter by 18% in the presence of magnetic NPs demonstrates that the NP magnetic moments are only weakly coupled to the nematic director and consequently only induce a disorder in the composite system. A significant influence of the expected large LC structural modifications in the presence of magnetic NPs is, however, shown by a particularly large increase of the diffusion coefficient 43% and large decrease of the dielectric anisotropy (43%). We believe that the observed impact of NPs with planar anchoring on nematic properties could be extended to most spherical NPs if their aggregation can be avoided. In particular, the difference between magnetic and nonmagnetic NPs could be extended to ferroelectric and nonferroelectric NPs.