Hydrogelation of a Naphthalene Diimide Appended Peptide Amphiphile and Its Application in Cell Imaging and Intracellular pH Sensing
作者:Nilotpal Singha、Purnima Gupta、Bapan Pramanik、Sahnawaz Ahmed、Antara Dasgupta、Anindita Ukil、Debapratim Das
DOI:10.1021/acs.biomac.7b01048
日期:2017.11.13
the molecules. With an increase in concentration, spherical aggregates are formed above 450 μM concentration. Importantly, this water-soluble conjugate was found to be nontoxic, cell permeable, and usable for cellimaging. Moreover, the aggregation process and consequently the emission behavior are highly responsive to the pH of the medium. Thus, the pH responsive aggregation and emission behavior
Electrografted monolayer based on a naphthalene diimide–ruthenium terpyridine complex dyad: efficient creation of large-area molecular junctions with high current densities
An electron donor-acceptor dyad has been designed for the creation of large-area molecular junctions (MJ). Diazonium cation electrografting was used to form well controlled monolayers. The robustness of the monolayer enabled the creation of MJs using direct top-coat evaporation with a high yield of operating devices.
Chiral Naphthalenediimides with High‐Efficiency Fluorescence and Circularly Polarized Luminescence in the Solid State for the Application in Organic Optoelectronics
conformation and self-assemble into discrete dimers in the solid state. The unique discrete dimeric stacking significantly promoted the fluorescence quantum yields and chiroptical properties via the formation of pre-associated excimers. The findings disrupt the general idea that non-core substituted NDIs cannot exhibit strong fluorescence in the solid state.
手性非核取代萘二亚胺 (NDI) 呈现 L 形构象,并在固态下自组装成离散二聚体。独特的离散二聚体堆叠通过预缔合准分子的形成显着提高了荧光量子产率和手性光学性质。这些发现打破了非核心取代的 NDI 在固态下不能表现出强荧光的一般观念。
Intra-Lysosomal Peptide Assembly for the High Selectivity Index against Cancer
targets for cancer therapy because cancercell proliferation is greatly dependent on effective lysosomal function. Recent studies have shown that lysosomal membrane permeabilization induces cell death and is an effective way to treat cancer by bypassing the classical caspase-dependent apoptotic pathway. However, most lysosome-targeted anticancer drugs have very low selectivity for cancercells. Here, we
溶酶体仍然是强大的细胞器和癌症治疗的重要靶点,因为癌细胞增殖很大程度上依赖于有效的溶酶体功能。最近的研究表明,溶酶体膜透化可诱导细胞死亡,是绕过经典的半胱天冬酶依赖性凋亡途径来治疗癌症的有效方法。然而,大多数溶酶体靶向抗癌药物对癌细胞的选择性非常低。在这里,我们展示了肽两亲物的溶酶体内自组装作为克服这一问题的强大技术。我们设计了一种肽两亲物,它位于癌症溶酶体中并进行组织蛋白酶 B 酶指导的超分子组装。这种局部组装会诱导溶酶体肿胀、膜通透和溶酶体损伤,最终导致癌细胞发生不依赖半胱天冬酶的细胞凋亡,无需常规化疗药物。它具有特异的抗癌作用,对耐药癌症有效。此外,这种肽两亲物在与肿瘤靶向配体连接时表现出高肿瘤靶向性,并在癌症和耐药癌症异种移植模型中显着抑制肿瘤生长。
Control of Rectification in Molecular Junctions: Contact Effects and Molecular Signature
作者:Quyen van Nguyen、Pascal Martin、Denis Frath、Maria Luisa Della Rocca、Frederic Lafolet、Clément Barraud、Philippe Lafarge、Vineetha Mukundan、David James、Richard L. McCreery、Jean-Christophe Lacroix
DOI:10.1021/jacs.7b05732
日期:2017.8.30
Thin layers of oligomers with thickness between 7 and 9 nm were deposited on flat gold electrode surfaces by electrochemical reduction of diazonium reagents, then a Ti(2 nm)/Au top contact was applied to complete a solid-state molecular junction. The molecular layers investigated included donor molecules with relatively high energy HOMO, molecules with high HOMO-LUMO gaps and acceptor molecules with low energy LUMO and terminal alkyl chain. Using an oligo(bisthienylbenzene) based layer, a molecule whose HOMO energy level in a vacuum is close to the Fermi level of the gold bottom electrode, the devices exhibit robust and highly reproducible rectification ratios above 1000 at low voltage (2.7 V). Higher current is observed when the bottom gold electrode is biased positively. When the molecular layer is based on a molecule with a high HOMO LUMO gap, i.e., tetrafluorobenzene, no rectification is observed, while the direction of rectification is reversed if the molecular layer consists of naphtalene diimides having low LUMO energy level. Rectification persisted at low temperature (7 K), and was activationless between 7 and 100 K. The results show that rectification is induced by the asymmetric contact but is also directly affected by orbital energies of the molecular layer. A "molecular signature" on transport through layers with thicknesses above those used when direct tunneling dominates is thus clearly observed, and the rectification mechanism is discussed in terms of Fermi level pinning and electronic coupling between molecules and contacts.