Self-assembled monolayers of 3‑Hydroxy‑N‑(5‑mercapto‑1,3,4‑thiadiazol‑2‑yl) benzamide (HMTB): A platform for Impedimetric sensing of Co(II)

New chalcone derivatives containing morpholine-thiadiazole: Design, synthesis and evaluation of against tobacco mosaic virus

Twenty chalcone derivatives containing morpholine-thiadiazole were designed and synthesized from the natural product chalcone. The bioactivity test results indicate that some compounds exhibit good antiviral activity against tobacco mosaic virus (TMV). In particular, the EC50 values for the curative and protective activity of S14 against TMV were 91.8 and 130.6 μg/mL, which was better than that of the antiviral agent ningnanmycin (NNM, 237.8, 220.6 μg/mL). The results of preliminary mechanism study indicated that S14 had strong binding capacity and affinity to tobacco mosaic virus coat protein (TMV-CP). In the chlorophyll content assay, the chlorophyll content of tobacco leaves increased significantly after the action of S14, so that it can enhance the photosynthetic capacity of plants. In addition, the results of malondialdehyde (MDA) content assay also indicated that S14 could improve the disease resistance of tobacco.

Role of Nanoscale Roughness and Polarity in Odd-Even Effect of Self-Assembled Monolayers

The dependency of substrate roughness on wetting properties of self-assembled monolayers (SAMs) has been studied extensively, but most previous studies used limited selection of probing liquid and range of surface roughness. These studies disregarded the limit to observation of sub-nanometer odd-even parity effect, hence are inconclusive. In this work we report the role of solvent polarity on the roughness-dependency of wetting behavior of SAMs by studying static con-tact angle of a variety of probing liquids, with different polarities, on SAMs formed on Ag-based substrate with different surface morphology. By overlapping the roughness ranges with previous studies on Au, the limitation of surface roughness (RMS=1 nm) to observation of the odd-even effect using water as probing liquid was confirmed, but other probing liquid yielded different roughness-dependent behaviors, with more polar solvent showing more roughness-dependent behavior. Based on these observations, we concluded that there exists a phase-transition like behavior in SAMs due to substrate roughness and molecule chain length, but whose determination is dependent on the probing liquid.