Fabrication of semiconductor nanowires by conjugation of quantum dots to actin filaments

We demonstrate the feasibility of fabrication of semiconducting nanowires (quantum dots) using F-actin as a template. Three different approaches of assembling quantum dots into nanowires are described. The nanowires were characterized by fluorescence microscopy.     

Leveraging Electron Transfer Dissociation for Site Selective Radical Generation: Applications for Peptide Epimer Analysis

Traditional electron-transfer dissociation (ETD) experiments operate through a complex combination of hydrogen abundant and hydrogen deficient fragmentation pathways, yielding c and z ions, side-chain losses, and disulfide bond scission. Herein, a novel dissociation pathway is reported, yielding homolytic cleavage of carbon–iodine bonds via electronic excitation. This observation is very similar to photodissociation experiments where homolytic cleavage of carbon–iodine bonds has been utilized previously, but ETD activation can be performed without addition of a laser to the mass spectrometer. Both loss of iodine and loss of hydrogen iodide are observed, with the abundance of the latter product being greatly enhanced for some peptides after additional collisional activation. These observations suggest a novel ETD fragmentation pathway involving temporary storage of the electron in a charge-reduced arginine side chain. Subsequent collisional activation of the peptide radical produced by loss of HI yields spectra dominated by radical-directed dissociation, which can be usefully employed for identification of peptide isomers, including epimers.

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木犀草素与胞嘧啶相互作用的理论研究

采用密度泛函理论中的B3LYP方法,在6-31＋G＊基组水平上对木犀草素、胞嘧啶、木犀草素-胞嘧啶复合物进行结构优化和振动频率分析,得到了12种稳定复合物.并应用分子中的原子理论（AIM）分析、自然键轨道（NBO）理论分析得到复合物氢键性质和特征.通过基组重叠误差（BSSE）校正后的相互作用能、成键临界点电荷密度、二阶...     

Off-on-off luminescent switching of a dye containing imidazo[4,5-f][1,10]phenanthroline

A new acid-base fluorescent switch containing both imidazo[4,5-f][1,10]-phenanthroline and triphenylamine groups has been synthesized.Its fluorescence emissions and absorptions can be reversibiy changed through protonation/deprotonation of imidazole and amine moiety by controlling the intramolecular charge transfer(ICT) process,leading to off-on-off fluorescent molecular switching.     

Sulfate encapsulation in a metal-assisted capsule based on a mono-pyridylurea ligand

A sulfate-encapsulating complex, [Cu(1)L(6)]·3[Cu(2)L(2)(DMF)(4)](SO(4))(4) (1, L = N-(1-naphthyl)-N'-(3-pyridyl)urea) is synthesized in which two C(3)-clefts of the octahedral complexes interdigitate to form a cavity to encapsulate the sulfate ion by six urea groups.