Four low-viscosity ionic liquids (ILs) based on the dicyanamide anion ([N(CN) 2 ] -), i.e., 1-butyl-3-methylimdazolium ([BMI][N(CN) ), have been investigated to determine their extraction capability for thiophene (TS) and dibenzothiophene (DBT) from model fuel oils. Aromatic imidazolium is more efficient than cyclic thiophenium and tetrahedral trialkylsulfonium; specifically, the S-extraction ability follows the orderwith DBT being more efficiently extracted than TS. The S-extraction of [BMI][N(CN) 2 ] has been investigated as a representative with respect to the influence of extraction temperature, IL : oil mass ratio, initial S-content, multiple extractions and reusability, along with its mutual solubility in oil. The percentage of S-removal from gasoline and diesel fuel were 48.5 and 68.7%, respectively, in a single extraction at 25 • C, 1 : 1(w/w) IL : oil, 5 min; the S-content in gasoline decreased from 599 ppm to 4 ppm after 5 extraction cycles and in diesel fuel decreased from 606 ppm to an undetectable value after 4 cycles. The mutual solubility is not pronounced and the extraction efficiency is not conspicuously changed after 6 regeneration cycles. It is worth noting that a short extraction time of < 5 min is observed for all the ILs at room temperature, which is understood by their low viscosities and effective mass transfer. This work may offer a new option for the deep desulfurization of fuel oils.

Water-soluble, biologically compatible CdSe quantum dots (QDs) with l-cysteine as capping agent were synthesized in aqueous medium. Fluorescence (FL) spectra, absorption spectra, and transmission electron microscopy studies showed that both the molar ratio of Se/Cd and the reaction time are the determining factors for the size distribution of CdSe/l-cysteine QDs. The interaction of QDs bioconjugated to bovine serum albumin (BSA) was also studied by absorption and FL titration experiments. With addition of QDs, the FL intensity of BSA was largely quenched, which can be explained by static mechanism. However, when BSA was added to the solution of QDs, FL intensity of QDs was faintly enhanced at first and then quenched. Lysozyme could change the Escherchia coli (E. coli) membrane fluidity and permeability by FL polarimetry. Fluorescent imaging suggested that QDs can be designed as a probe to label the E. coli cell. These results suggested CdSe/l-cysteine QDs can be used as a probe for labeling biological molecule and bacteria cell.

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Implant-associated bacterial infections pose serious medical and financial issues due to the colonization and proliferation of pathogens on the surface of the implant. The as-prepared traditional antibacterial surfaces can neither resist bacterial adhesion nor inhibit the development of biofilm over the long term. Herein, novel (montmorillonite/poly-l-lysine-gentamicin sulfate) ((MMT/PLL-GS)) organic-inorganic hybrid multilayer films were developed to combine enzymatic degradation PLL for on-demand self-defense antibiotics release. Small molecule GS was loaded into the multilayer films during self-assembly and the multilayer films showed pH-dependent and linear growth behavior. The chymotrypsin- (CMS) and bacterial infections-responsive film degradation led to the peeling of the films and GS release. Enzyme-responsive GS release exhibited CMS concentration dependence as measured by the size of the inhibition zone and SEM images. Notably, the obtained antibacterial films showed highly efficient bactericidal activity which killed more than 99.9% of S. aureus in 12 h. Even after 3 d of incubation in S. aureus, E. coli or S. epidermidis solutions, the multilayer films exhibited inhibition zones of more than 1.5 mm in size. Both in vitro and in vivo antibacterial tests indicated good cell compatibility, and anti-inflammatory, and long-term bacterial anti-adhesion and biofilm inhibition properties.