A specific ion-pair approach can be involved in precise control of the size of gold nanodots. The dendrimers with terminal amine and hydroxyl groups were a hydrophilic and hydrophobic microcavity-template, respectively, for trapping gold salts. The facile strategy can significantly enhance the quantum yield of gold nanodots from 20% to 62% after microwave irradiation.

This paper intends to discuss the economical performances and CO2 reduction potential of two CO2-based dimethyl carbonate (DMC) production processes through rigorous process simulation. One of them is the direct production process with addition of butylene oxide (BO) as dehydrating agent (DIR-BO porocess), while the other is the indirect production process through ethylene carbonate (EC) as an intermediate (IND-EC process). Both processes are systematically optimized and heat-integrated. From economical evaluation, the IND-EC process exhibits economical attractiveness, while the DIR-BO process does not. We suggest that once the reaction rate of the DIR-BO process can be improved, the overall economic performance of the direct process can be much better. From the aspect of CO2 reduction, the net CO2 emissions throughout both processes are calculated. We found that DIR-EO process is largely carbon positive, with CO2 emission of 2.242 (kg CO2/kg DMC), yet for the IND-EC process, it is near carbon neutral, with CO2 emission of 0.049 (kg CO2/kg DMC). Thus, from the aspect of achieving CO2 reduction, converting it into DMC provides limited benefits.

Ionic liquids (ILs) have received much attention in the last two decades. One of the important applications is to use this relatively new class of compounds for the separation of azeotropic mixtures via extractive distillation. In this paper, overall extractive distillation processes of two azeotropic separation systems using a favorable ionic liquid as entrainer are rigorously developed. The optimized design flowsheets are compared with the conventional processes using an industrial entrainer. The two ionic liquid extractive distillation systems include separating acetone and methanol using 1,3-dimethylimidazolium dimethylphosphate ([MMIM][DMP]) as entrainer and another system of separating isopropyl alcohol and water using 1-ethyl-3-methylimidazolium acetate ([EMIM][OAC]) as entrainer. The potential drawbacks of using an ionic liquid in the extractive distillation systems are given in the paper. It is found that the degradation temperature and high normal boiling point temperature of the ionic liquids in these two systems require the IL processes to use high vacuum operating conditions, thus making them only economically comparable to the conventional processes.

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The growth factor receptor-bound protein Src homology 2 (Grb2-SH2) plays an important role in the oncogenic Ras signaling pathway, which involves in cell proliferation and differentiation. Therefore, the antagonist of Grb2-SH2 has become a potential target for developing anticancer agents. Recently, we discovered a peptide 1 (Fmoc-Glu-Tyr-Aib-Asn-NH(2)) with high affinity for the Grb2-SH2 domain by using surface plasmon resonance (SPR)-biosensor technology. Herein, we report the further design of the lead peptide 1 by addition of an Arg-Gly-Asp sequence to 1 to enhance binding to Grb2-SH2 and inducing apoptosis in cancer cells. Both the linear and cyclic analogs of the newly designed compound were prepared along with an analog in which the N(alpha)-Fmoc group was removed. These peptide analogs were assayed for their affinity for the Grb2-SH2, their antiproliferative effect on human breast cancer cells, their specificity for cancer cells, and their effects on cytotoxicity and the cell cycle. MCF-7 and MDA-MB-453 breast cancer cells were treated with various concentrations of each peptide. The cell viability and cytotoxicity of peptide-treated cells were determined by using the cell proliferation kit (3-[4, 5-dimethyl-2-thiazolyl]-2, 5-diphenyl-tetrazolium bromide, MTT) and cytotoxicity kit (lactate dehydrogenase, LDH), respectively. Effects of peptides on the cell cycle progression of cancer cells and apoptosis were analyzed by using flow cytometry. Results demonstrated that the peptide analog 2 (H-Arg-Gly-Asp-Glu-Tyr-Aib-Asn-Arg-Gly-Asp-NH(2)) had anti-proliferative effects on MCF-7 and MDA-MB-453 cells with an IC(50) of 45.7 microM and 47.4 microM, respectively. The cytotoxicity and percentage of sub-G1 in the cell cycle were increased in these cancer cells when cells were treated with higher concentration of the Arg-Gly-Asp-containing peptide 2. These results provide important information for the development of anti-cancer agents.