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The fluorescence detection of ions and pharmaceutical effluents by using organic chemosensors is a valuable surrogate to the currently existing expensive analytical methods. In this regard, the design of multi-functional chemosensors to recognize desirable guests is of utmost importance. In this study, we first show that levofloxacin (LVO) is able to use as a fluorescent chemosensor for the detection of biologically important Cu2+ (turn-off) and Fe3+ (turn-on) ions via independent signal outputs in 100% aqueous buffer solutions. Next, using the reciprocal recognition of LVO and Fe3+ provides a unique emission pattern for the detection of LVO. This approach exhibited a high specificity to LVO among various pharmaceutical samples, namely acetaminophen (AC), azithromycin (AZ), gemifloxacin (GEM) and ciprofloxacin (CIP) and also showed great anti-interference property in urine. The attractive features of this sensing system are availability, easy-to-use, high sensitivity (limit of detection = 18 nM for Cu2+, 22 nM for Fe3+ and 0.12 nM for LVO), rapid response (5 s) with an excellent selectivity. Levofloxacin (LVO) is able to use as a fluorescent chemosensor for the detection of Cu2+ (turn-off) and Fe3+ (turn-on) ions via independent signal outputs. Moreover, using the reciprocal recognition of LVO and Fe3+ a unique emission pattern for the detection of LVO was achieved which is applicable for biological samples. The attractive features of this sensing system are availability, easy-to-use, high sensitivity, rapid response (5 s) with an excellent selectivity. [ABSTRACT FROM AUTHOR]

In this regard, two choline chloride-based deep eutectic solvents (as reactants and reaction media), namely ChCl/oxalic acid and ChCl/benzene-1,2-diamine have been introduced to access quinoxaline-2,3-diol derivatives. Deep eutectic solvents (DESs) have emerged as alternative sustainable media to classical volatile solvents due to their low vapor pressure and low flammability.[1] Among DESs utilized for organic synthesis, eutectic mixtures based on choline chloride (ChCl) are the most reported in the literature. Taking into account the potentiality of arene-1,2-diamines to react with an organic hydrogen bond donor in a eutectic mixture, it was thought that oxalic acid, like urea, would be a good candidate (as reactant) for this purpose. It can be seen that in both cases the oxalic acid (as eutectic component in DES-1 and reactant in DES-2) to I ortho i -PD molar ratio should be higher than 1. [Extracted from the article]

The synthesis of 2‐benzimidazolone and 2‐imidazolone derivatives from urea as an inexpensive widely available carbonyl source is usually performed in high boiling organic solvents accompanied by ammonia evolution, due to urea decomposition. In this paper, a sustainable method has been introduced for the synthesis of these N,N‐heterocycles by employing zinc chloride:urea (1 : 3.5) type IV eutectic mixture under mild reaction conditions. No urea was used directly in the reaction owing to the fact that the eutectic mixture (containing urea itself) suffice to provide the carbonylation source. This new concept allowed the smooth conversion of a range of arene‐1,2‐diamines and benzoins to the corresponding N,N‐heterocycle in efficient yields. The remarkable advantage of this green protocol over other conventional heating procedures is that all reactions are conducted under open‐vessel conditions due to the absorption of the evolved ammonia by the eutectic mixture during the reaction process. (© WILEY‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [ABSTRACT FROM AUTHOR]

Titanium oxide nano-layers were fabricated by a direct electrodeposition method, including Ti as anode and stainless steel as cathode in a non-aqueous media. The applied voltage, electrodeposition time and amount of water in the electrolyte were taken as control parameters to obtain highly stable nano-layers. The prepared samples were characterized by scanning electron microscopy, atomic force microscopy, ellipsometric spectroscopy and energy dispersive X-ray analysis. The fabricated samples showed remarkably high stability and acceptable photocatalytic behavior towards the photodegradation of methylene blue (MB). The best result found for degradation of MB is obtained by nano-layer electrodeposited at 15 V for 30 min. These nano-layers could be reused at least 30 times without any perceptible loss of the photocatalytic activity. The attractive features of this simple process are operational simplicity, decrease of precursors consumption, photocatalytic performance of thin layers without any heat treatment (no annealing is required), and, above all, high stability of thin layers in both static and flowing environments, which make it a useful strategy for the degradation of the pollutants such as MB. [ABSTRACT FROM AUTHOR]

In this study, bulk TiO2 nanorods are synthesized by hydrothermal method in order to be used in the dye-sensitized solar cells (DSSCs). These nanorods are annealed at different temperatures and deposited electrophoretically. The influence of post heat treatment has been thoroughly investigated on fabricated DSSCs using electrochemical impedance spectroscopy (EIS). The results have revealed that the diameter, size and density of the prepared bulk nanorods are function of annealing temperatures. Optimization of the prepared DSSCs has led to an improved efficiency (ca. 3.82%) under AM 1.5 simulated sunlight. [ABSTRACT FROM AUTHOR]