Marine oil spills constitute an environmental disaster with severe adverse effects on the economy and ecosystem. Phase-selective organogelators (PSOGs), molecules that can congeal oil selectively from oil-water mixtures, have been proposed to be useful for oil-spill recovery. However, a major drawback lies in the mode of application of the PSOG to an oil spill spread over a large area. The proposed method of using carrier solvents is impractical for various reasons. Direct application of the PSOG as a solid, although it would be ideal, is unknown, presumably owing to poor dispersion of the solid through the oil. We have designed five cheap and easy-to-make glucose-derived PSOGs that disperse in the oil phase uniformly when applied as a fine powder. These gelators were shown to selectively congeal many oils, including crude oil, from oil-water mixtures to form stable gels, which is an essential property for efficient oil-spill recovery. We have demonstrated that these PSOGs can be applied aerially as a solid powder onto a mixture of crude oil and sea water and the congealed oil can then be scooped out. Our innovative mode of application and low cost of the PSOG offers a practical solution to oil-spill recovery.

Marine oil spills constitute an environmental disaster with severe adverse effects on the economy and ecosystem. Phase-selective organogelators (PSOGs), molecules that can congeal oil selectively from oil-water mixtures,h ave been proposed to be useful for oil-spill recovery.However,amajor drawbacklies in the mode of application of the PSOG to an oil spill spread over al arge area. The proposed method of using carrier solvents is impractical for various reasons.D irect application of the PSOG as asolid, although it would be ideal, is unknown, presumably owing to poor dispersion of the solid through the oil. We have designed five cheap and easy-to-make glucose-derived PSOGs that disperse in the oil phase uniformly when applied as af ine powder.T hese gelators were shown to selectively congeal many oils,i ncluding crude oil, from oil-water mixtures to form stable gels,w hich is an essential property for efficient oil-spill recovery.W eh ave demonstrated that these PSOGs can be applied aerially as as olid powder onto am ixture of crude oil and sea water and the congealed oil can then be scooped out. Our innovative mode of application and low cost of the PSOG offers apractical solution to oil-spill recovery.

Amitriptyline hydrochloride is an antidepressant drug with sedative effects used to treat the symptoms of anxiety, agitation with depression and schizophrenia with depression. A reversed‐phase high‐performance liquid chromatography method was developed to separate and quantitatively determine the assay and four organic impurities of amitriptyline in tablet dosage form and bulk drugs using a C18 column in an isocratic elution mode with mobile phase consisting of a mixture of pH 7.5 phosphate buffer and methanol. The pH conditions used in the chromatographic separation are discussed. The stability‐indicating characteristics of the proposed method were proved using stress testing [5 m HCl at 80°C/1 h, 5 m NaOH at 80°C/1 h, H2O (v/w) at 80°C/1 h, 6% H2O2 (v/v) at 25°C/1 h, dry heat at 105°C/24 h and UV–vis light/4 days] and validated for specificity, detection limit, quantitation limit, linearity, precision, accuracy and robustness. For amitriptyline and its four known organic impurities, the quantitation limits, linearity and recoveries were in the ranges 0.25–3.0 μg/ml (r2 > 0.999) and 87.9–107.6%, respectively. The mass (m/z) spectral data of amitriptyline hydrochloride and its impurity are discussed. The proposed LC method is also suitable for impurity profiling and assay determination of amitriptyline in bulk drugs and pharmaceutical formulations.

Montelukast sodium (MLS) is a leukotriene receptor antagonist drug used in the treatment of asthma, bronchospasm, allergic rhinitis and urticaria. A reversed-phase high performance liquid chromatography method was developed to separate, identify and quantitative determination of MLS and its eight known organic impurities in tablet dosage form using a C 18 column and mobile phases consisting of a gradient mixture of pH 2.5 phosphate buffer and acetonitrile. The stability-indicating character of the developed method was proven using stress testing (1 M HCl at 80 C/30 min, 1 M NaOH at 80 C/30 min, H 2 O at 80 C/30 min, 3% H 2 O 2 at 25 C/1 min, dry heat at 105 C/10 h and UV-vis light/4 days) and was validated for specificity, quantitation limit, linearity, precision, accuracy and robustness. For MLS and its eight known impurities, the quantitation limits, linearity and recoveries were 0.015-0.03 μg/ml, correlation coefficient > 0.997 (R 2 > 0.995) and 85.5-107.0%, respectively. The developed chromatographic method is suitable for impurity profiling and also for assay determination of MLS in bulk drugs and pharmaceutical formulations. The mass values (m/z) of newly formed degradation products (DP1 and DP2) of montelukast sodium were identified using liquid chromatography-mass spectrometry.

We investigate L-Tyrosine as an efficient catalyst for the Knoevenagel condensation of arylaldehydes with meldrum’s acid containing cyclic active methylene group in solvent-free condition under grindstone method at room temperature to produce substituted-5-benzylidene-2,2-dimethyl-[1,3]dioxane-4,6-diones 3(a–j).