Delivering of Resveratrol with Solid Lipid Nanoparticles Improved Mitochondria Activity

Skin is main target for UV-oxidative stress and their antioxidant defenses can be quickly overcome. [...

Effect of resveratrol incorporated in liposomes on proliferation and UV-B protection of cells

The possibility of improving the efficacy of resveratrol, a polyphenol with strong antioxidant and free-radical scavenging properties, on cell proliferation and photoprotection by liposomal incorporation was investigated. Oligolamellar vesicles of different lipid compositions, loaded with resveratrol, were prepared and characterized by evaluating size, zeta potential, incorporation efficiency, electron microscopy and stability over 60 days. The effect of free and liposomal resveratrol on the viability of HEK 293 cells and their photoprotection after UV-B irradiation was assessed by the MTS method. Resveratrol decreased the cell viability at 100microM concentration, while at 10microM increased cell proliferation and also achieved the most effective photoprotection. Photomicrographs of the treated cells from inverted light and fluorescence microscopy demonstrated resveratrol effectiveness at 10microM, as well as its toxicity at higher concentrations, based on changes in cell shape, detachment and apoptotic features. Interestingly, liposomes prevented the cytotoxicity of resveratrol at high concentrations, even at 100microM, avoiding its immediate and massive intracellular distribution, and increased the ability of resveratrol to stimulate the proliferation of the cells and their ability to survive under stress conditions caused by UV-B light

Interfacial rheology: An overview of measuring techniques and its role in dispersions and electrospinning

Interfacial rheological properties have yet to be thoroughly explored. Only recently, methods have been introduced that provide sufficient sensitivity to reliably determine viscoelastic interfacial properties. In general, interfacial rheology describes the relationship between the deformation of an interface and the stresses exerted on it. Due to the variety in deformations of the interfacial layer (shear and expansions or compressions), the field of interfacial rheology is divided into the subcategories of shear and dilatational rheology. While shear rheology is primarily linked to the long-term stability of dispersions, dilatational rheology provides information regarding short-term stability. Interfacial rheological characteristics become relevant in systems with large interfacial areas, such as emulsions and foams, and in processes that lead to a large increase in the interfacial area such as electrospinning of nanofibers.Medfazne reološke lastnosti so še dokaj neraziskane. Šele pred kratkim so razvili metode, s katerimi je mogoče z zadostno občutljivostjo in natančnostjo določiti viskoelastične lastnosti medfaze. Medfazna reologija opisuje odnos med deformacijo medfaze in silo, ki to deformacijo povzroči. Zaradi različnih deformacij medfazne plasti (strig in raztezanje, oziroma krčenje) se tudi medfazna reologija deli na strižno in dilatacijsko. Strižne reološke lastnosti medfaze se odražajo v dolgotrajni stabilnosti disperzij, medtem ko sedilatacijske predvsem v kratkotrajni stabilnosti. Poznavanje medfaznih reoloških lastnosti je pomembno v sistemih z velikimi medfaznimi površinami, kot so emulzije in pene ter pri procesih, kjer pride do velikega povečanja medfazne površine, kot je elektrostatsko sukanje nanovlaken