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The human skin is a recurring target of external aggressions, such as UV radiation, leading to exacerbation of the aging process and the occurrence of skin diseases, such as cancer. Hence, preventive measures should be taken to protect it against these aggressions, consequently decreasing the chance of disease development. In the present study, a topical xanthan gum nanogel containing gamma-oryzanol-loaded nanostructured lipid carriers (NLCs) and nanosized UV filters TiO2 and methylene bis-benzotriazolyl tetramethylbutylphenol (MBBT) was developed to assess their synergistic potential in having multifunctional skin beneficial properties. The developed NLCs contained the natural-based solid lipids shea butter and beeswax, liquid lipid carrot seed oil, and the potent antioxidant gamma-oryzanol, with an optimum particle size for topical application (<150 nm), good homogeneity (PDI = 0.216), high zeta potential (−34.9 mV), suitable pH value (6), good physical stability, high encapsulation efficiency (90%), and controlled release. The final formulation, a nanogel containing the developed NLCs and the nano UV filters, showed high long-term storage stability and high photoprotection ability (SPF = 34) and resulted in no skin irritation or sensitization (rat model). Hence, the developed formulation showed good skin protection and compatibility, demonstrating promise as a new platform for the future generation of natural-based cosmeceuticals. [ABSTRACT FROM AUTHOR]

Sulfamic acid‐functionalized Fe3‐xTixO4 nanoparticles (Fe3‐xTixO4‐SO3H NPs) were fabricated as novel acidic magnetic nanocatalyst by the reaction of Fe3‐xTixO4 magnetic nanoparticles (MNPs) with 3‐chloropropyltrimethoxysilyl urea (TMSPU) followed by functionalization with chlorosulfonic acid. The structure of the synthesized nanocatalyst was studied using different methods including, Fourier‐transform infrared (FT‐IR), field‐emission scanning electron microscopy (FE‐SEM), transmission electron microscopy (TEM), powder X‐ray diffraction (XRD), energy‐dispersive X‐ray spectroscopy (EDX), thermogravimetric analysis (TGA), vibrating sample magnetometer (VSM), and dynamic light scattering (DLS). The potential catalytic ability of the synthesized MNPs was studied in one‐pot four‐component condensation reaction between aromatic aldehydes, dimedone, alkyl acetoacetates and ammonium acetate in order to synthesis of hexahydroquinoline derivatives. It was witnessed that the reactions proceeded smoothly under solvent‐free condition with high yields of corresponding hexahydroquinolines. Sulfamic acid‐functionalized Fe3‐xTixO4 nanoparticles (Fe3‐xTixO4‐SO3H NPs) were fabricated as novel acidic magnetic nanocatalytic for the synthesis of hexahydroquinolines under green solvent‐free condition through one‐pot four‐component condensation reaction. [ABSTRACT FROM AUTHOR]

The amino acid ionic liquid tetrabutylammonium asparaginate (TBAAsp) was immobilized on titanomagnetite (Fe3− xTi xO4) nanoparticles in a facile one-pot process using an organosilane compound (TMSP) as spacer. The modified Fe3− xTi xO4@TMSP@TBAAsp magnetic nanoparticles were characterized using Fourier transform spectroscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, vibrating sample magnetometry and thermogravimetric analysis. The resulting analytical data clearly verified the successful immobilization of the ionic liquid on the magnetic substrate. The magnetic ionic liquid-based nanoparticles exhibited high catalytic activity in the synthesis of 1,4-dihydropyrano[2,3- c]pyrazole derivatives via a one-pot three-component reaction under mild reaction conditions. The catalyst was easily recycled and reused for at least six runs without any considerable loss of activity. [ABSTRACT FROM AUTHOR]

In the present study, for the first time N-(3-silyl propyl) diethylene triamine N,N',N''-tri-sulfonic acid (SPDETATSA) was grafted on magnetic Fe3-xTixO4 nanoparticles. The structure of the resulted nanoparticles was characterized based on Fourier-transform infrared (FT-IR), energy-dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermal gravimetric analysis (TGA), and vibrating sample magnetometer (VSM) analyses. The results confirmed the successful immobilization of sulfamic acid groups onto the magnetic support. These nanoparticles exhibited high catalytic activity as novel magnetically recyclable acid nanocatalyst in the synthesis of a diverse range of hexahydroquinolines through one-pot tandem reactions in excellent yields. Also, this nanocatalyst performed satisfactory catalytic maintenance of activity for the synthesis of the reaction products after 4 rounds of recycling with no considerable loss of activity. [ABSTRACT FROM AUTHOR]

Silica-modified magnetite-polyoxometalates functionalized with sulfamic acid groups as hybrid nanoparticles were prepared by sulfonation of diamine-functionalized propyl group grafted on the magnetic silica-coated Fe3O4nanoparticles. This heterogeneous nanocatalyst was explored to present high catalytic performance for the synthesis of 3,4-dihydropyrimidinones and tetrahydrobenzo[b]pyrans under mild reaction conditions. The properties of this nanocatalyst were characterized by FT- infrared, energy-dispersive X-ray spectrum, scanning electron microscope, X-ray diffraction, X-ray fluorescence and elemental analysis. Easy separation of the nanocatalyst by using an external magnet, recyclability, non-toxicity, versatility and high stability of the catalyst combined with low reaction times and excellent yields make the present protocol very useful and attractive for the synthesis of the titled products. [ABSTRACT FROM AUTHOR]