In this study, a rapid chiral separation of 12 cathinones analogs has been developed and validated using cyclodextrin-assisted CE with UV and TOF-MS detection. Optimum separation was obtained on a 57.5 cm × 50 μm capillary using a buffer system consisting of 10 mM β-cyclodextrin (β-CD) in a 100 mM phosphate buffer for CE-UV, and 0.6% v/v highly sulfated-γ-cyclodextrin (HS-γ-CD) in a 50 mM phosphate buffer for CE-MS. In the CE-MS experiment, a partial filling technique was employed to ensure that a minimum amount of cyclodextrin entered the mass spectrometer. All analytes were separated within 18 min in the CE-UV separation and identified by TOF-MS. Ten compounds were enantiomerically separated using β-CD in the UV mode and an additional two more were enantiomerically separated using HS-γ-CD in the MS mode. Detection limits down to 1.0 ng/mL were obtained. The method was then applied to examine seized drugs.

DOSS − (dioctyl sulfosuccinate) based quaternary ammonium ionic liquids (QAILs) were synthesized and used as both neat lubricants and lubricant additives. The influence of structure on their miscibility, thermal stability, and tribological property was discussed. These QAILs are low cost as compared with conventional halogen-containing ionic liquids (ILs). They are noncorrosive and hydrolysis stable because of their halogen-free characteristics. The tribological properties of these QAILs as neat lubricants for steel/steel and steel/copper contacts are found to be better than conventional halogen-containing ILs 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (L-F104) and far better than traditional synthetic lubricant poly-α-olefin (PAO). Moreover, oil-soluble ILs were obtained by properly adjusting the chain length and cation asymmetry of these QAILs, which can be easily dissolved in nonpolar synthetic-oil PAO. They are found to be effective lubricant additives for improving the friction-reducing and antiwear properties of PAO. It is a great advantage as compared with conventional ILs, which have extremely low solubility in PAO and are difficult to be used as lubricant additives for this kind of base oil. Furthermore, the coking test results indicated that the synthesized QAILs have high deterging ability when used as lubricant additives for PAO. Thus, they can restrain carbonaceous deposition as well as oil sludge and varnish formation on the metal contacts during the sliding process. They can also disperse, loosen, and remove the already formed harmful substances and keep the metal contacts clean. The present work may make obvious progress toward preparing low cost, noncorrosive, and environmentally benign IL lubricants in lubrication engineering.

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This article described the synthesis and application of 6-chloro-8-fluoro-4-methylumbelliferone phosphate (CF-MUP) in analyzing acid phosphatase activity. Compared to the existing MUP, the new coumarin phosphate, CF-MUP, demonstrateed much higher sensitivity and was more robust for detecting the activity of acid phosphatase than the classic substrate 4-methylumbelliferone phosphate (MUP). The product of enzyme reaction, 6-chloro-8-fluoro-4-methylumbelliferone (CF-MU) possesses strong fluorescence at ~450 nm with low pKa (4.7), high fluorescence quantum yield and pH independence in the physiological pH range. This new fluorescence dye, CF-MU, is a convenient tool for assays with buffer pH between 4.5 and 8.

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