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Chlorogenic acid (CGA) was thiolated using Traut's reagent. Then, thiolated chlorogenic acid (CAT) functionalized on the silver nanoparticles (AgNPs). The resulting CAT-functionalized silver nanoparticles (CAT-AgNPs) have higher stability with a uniform spherical shape compared to naked AgNPs. The average particle size is 10 nm, as revealed by transmission electron microscopy (TEM). The antimicrobial activity was higher against both gram-positive and gram-negative bacteria of spherically stable nanoparticles evaluated by the disk diffusion method. Minimal inhibitory concentration (MIC) values for CAT-AgNPs were 130 µg/ml for Staphylococcus aureus and 150 µg/ml for Escherichia coli. Cytotoxicity studies showed that the CAT-AgNPs show maximum activity against MCF-07 cell lines with an IC50 value of 20 ng/ml. Compared to traditional noncovalent interactions, the Ag–S covalent linkage of CAT with AgNPs helped in highly stable capping. The prepared CAT-AgNPs show anticancer and antibacterial activities, thus providing an efficient antimicrobial nano-drug carrier. Nanoparticles with a dual-mode of action help in preventing fouling of nanocarriers while delivering drugs to targeted cells, opening up many applications in nanobiotechnology and nanomedicine. [ABSTRACT FROM AUTHOR]

The present paper provides a simple mathematical model that describes the synergistic interaction of environmental factors that occur in urban ecosystem. The model predicts the value of maximum synergistic action and the condition for its achievement, as well as implies the dependence of synergistic action on the intensity of the agents used and the proportion of irreversible damages after the combined effects. The developed mathematical model can be used to predict the accumulation of pollution in the ground layer of soil. [ABSTRACT FROM AUTHOR]

A tripod rhodamine derivative (L) with flexible chains was synthesized through linking tris(2-aminoethyl)amine appended rhodamine and two thiophene groups. Based on the synergetic action of the acidic medium provided by trivalent metal ions and stability complex came from trivalent metal ions and probe L, the probe displayed higher selectivity and sensitivity in CH 3 OH/H 2 O (1/3) solution. The formation of these complexes caused a new absorption peak appearance at 555 nm along with color changes of the solution. Meanwhile, a drive fluorescence behaviors of probe L by the trivalent metal ions were observed with a dramatical enhancement of the fluorescence at 585 nm, respectively. Interestingly, introducing EDTA to the probe L/Fe(III) complex, the fluorescence intensity of the complex was further enhanced. Based on the high throughput analysis strategy, the probe L was designed as a logic gate for detecting trivalent metal ions. Typically, the combination ratio of the probe L with Fe(III) was 1/1 (mole), which was obtained by Job-plot experiment and further confirmed by DFT calculations. Moreover, the tripod rhodamine derivative as a “turn-on” fluorescence switch was applied to detect Fe(III) in actual sample. [ABSTRACT FROM AUTHOR]

Au, Se and porphyrin are widely used components in the design of anticancer drugs, but their combination has never been referred to. In this work, a Se-modified porphyrin Au(III) complex, [AuTPP-Se]Cl, was designed and synthesized as a potential anticancer agent. This compound exhibits remarkable antiproliferative activity on all the six tested cancer cells. Its potency on HepG2 is even ten times higher than that of CDDP. The synergistic action among Au, Se and porphyrin components was validated. Mechanism study showed that both the induction of mitochondria-dependent apoptosis and the arrest of cell cycle contribute to the anticancer activity of [AuTPP-Se]Cl. [ABSTRACT FROM AUTHOR]

Objective To explore the suitable level and action time of l7-β estradiol and fluid shear stress (FSS) and their combined effect on the proliferation of rat osteoblasts in Vitro. Methods MC3T3-E1 osteoblasts were adopted after subcultured and different concentrations of 17-β estradiol and FSS values were applied respectively on MC3T3- E1, the suitable level of 17-β estradiol and FSS were selected through MTT and alkaline phosphatase (ALP). Then the two factors at the suitable level were applied simultaneously to MC3T3-E1 to detect the proliferation activity. Results Seventeen-β estradiol(10-18 mol L-1 ) for 5 d and 12x10-5 N FSS for 60 mm exhibited better effects on the proliferation activity than the other groups respectively, and the combined effect of both factors was better than any single-factor treated group. Conclusion Both l7-β estradiol and FSS have a suitable threshold in promoting proliferation of osteoblasts, and two-factor treated group exhibits better effect than any other single-factor treated groups. Therefore 17-β estradiol and FSS have a synergetic action on differentiation and proliferation of osteoblasts. [ABSTRACT FROM AUTHOR]

Ni-based self-lubricating composites with multiple-lubricants addition were prepared by a powder metallurgy technique, and the effect of multiple-lubricants on tribological properties was investigated from room temperature to 700 °C. The synergetic effects of graphite, MoS, and metallic silver lubricants on the tribological characteristics of composites were analyzed. XRD analysis showed that new CrS and MoC phase were formed in the composites containing graphite, MoS and metallic Ag lubricants during the sintering process. The average friction coefficients (0.69-0.22) and wear rates (11.90-0.09 × 10 mm N m) were obtained when rubbing against Inconel 718 alloy from room temperature to 700 °C due to synergetic lubricating action of multiple-lubricants. A smooth lubricating was gradually generated on the worn surface, and the improving of tribological properties was attributed to the formation of lubricious glaze film on the worn surface and their partially transferred to the counterface. The graphite played the main role of lubrication at room temperature, while molybdate phase and graphite were responsible for low friction coefficients and wear rates at mid/high temperatures. The synergetic lubricating effect of molybdate (produced in the rubbing process at high temperatures) iron oxide (transfer from disk material to the pin) and remaining graphite multiple-lubricants play an important lubricating role during friction tests at a wide temperature range. [ABSTRACT FROM AUTHOR]