Advanced design of a x-ray absorption spectroscopy setup for measuring transition metals speciation in molten carbonates, hydroxides and hydrogenosulfates.

Battery recycling is currently becoming a crucial issue. One possible treatment path involves the use of molten salts. A mechanistic understanding of the underlying processes requires being able to analyze in situ speciation in molten salts at various temperatures. This can be advantageously achieved using x-ray absorption spectroscopy, the use of Quick-EXAFS facilities being particularly appropriate. Consequently, this paper presents the design and development of a new setup allowing carrying out Quick-EXAFS experiments in oxidizing molten salts at high temperatures. We describe the different components of a cell and the performance of the heating device. We illustrate the capabilities of the setup by analyzing the temperature evolution of Co speciation upon dissolution of LiCoO2, a typical battery electrode material, in molten carbonates, hydroxides, and hydrogenosulphates.

Paronychia argentea Lam. protects renal endothelial cells against oxidative injury.

ETHNOPHARMACOLOGICAL RELEVANCE: Paronychia argentea Lam. (Arabic tea), a species spontaneously growing in the Mediterranean area, has been used in folk medicine for renal diseases. AIM OF THE STUDY: To assess the antioxidant and protective potentials of different extracts from P. argentea in the renal endothelial NRK-52E cell line by several in vitro models, including a H2O2-induced oxidative stress model. MATERIAL AND METHODS: Aerial parts of P. argentea were collected in Algeria and ethanolic, chloroform and aqueous-chloroform extracts were obtained from dried plant. The antioxidant capacity was first evaluated by the Oxygen Radical Absorbance Capacity (ORAC) and the free radical scavenging activity (DPPH) methods. Cellular viability was assessed by MTT method assay after 24 h pretreatment with each extract concentration in order to measure protection from H2O2 in NRK-52E cells. Furthermore, the intracellular ROS formation (DCFH-DA method), was determined. RESULTS: P. argentea showed in vitro antioxidant activity as evidenced by the ORAC and DPPH assays. No cell toxicity was observed for concentrations ranging from 0.1 to 100 µg/mL of each extract. These extracts also exerted a protective effect on renal endothelial cells simultaneously treated with 1 mM H2O2. Chemical composition for the aqueous-chloroform extract was assessed by HPLC, as it showed the strongest antioxidant ability, revealing three quercetin derivatives as the main phenolic compounds. CONCLUSION: P. argentea is endorsed with antioxidant activity and protects renal endothelial cells against oxidative damage which indicate this plant constitutes a potential treatment for renal diseases.