Organic and printed electronics technologies require conductors with a work function that is sufficiently low to facilitate the transport of electrons in and out of various optoelectronic devices. We show that surface modifiers based on polymers containing simple aliphatic amine groups substantially reduce the work function of conductors including metals, transparent conductive metal oxides, conducting polymers, and graphene. The reduction arises from physisorption of the neutral polymer, which turns the modified conductors into efficient electron-selective electrodes in organic optoelectronic devices. These polymer surface modifiers are processed in air from solution, providing an appealing alternative to chemically reactive low-work function metals. Their use can pave the way to simplified manufacturing of low-cost and large-area organic electronic technologies.

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For Ras oncoproteins to transform mammalian cells, they must be post-translationally modified with a farnesyl group in a reaction catalysed by the enzyme farnesyl-protein transferase (FPTase). Inhibitors of FPTase have therefore been proposed as anti-cancer agents. We show that L-744,832, which mimics the CaaX motif to which the farnesyl group is added, is a potent and selective inhibitor of FPTase. In MMTV-v-Ha-ras mice bearing palpable tumours, daily administration of L-744,832 caused tumour regression. Following cessation of treatment, tumours reappeared, the majority of which regressed upon retreatment. No systemic toxicity was found upon necropsy of L-744,832-treated mice. This first demonstration of anti-FPTase-mediated tumour regression suggests that FPTase inhibitors may be safe and effective anti-tumour agents in some cancers.

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Nanoporous zeolitic imidazolate frameworks (ZIFs) form structural topologies equivalent to zeolites. ZIFs containing only one type of imidazole linker show separation capability for limited molecular pairs. We show that the effective pore size, hydrophilicity, and organophilicity of ZIFs can be continuously and drastically tuned using mixed-linker ZIFs containing two types of linkers, allowing their use as a more general molecular separation platform. We illustrate this remarkable behavior by adsorption and diffusion measurements of hydrocarbons, alcohols, and water in mixed-linker ZIF-8(x)-90(100-x) materials with a large range of crystal sizes (338 nm to 120 μm), using volumetric, gravimetric, and PFG-NMR methods. NMR, powder FT-Raman, and micro-Raman spectroscopy unambiguously confirm the mixed-linker nature of individual ZIF crystals. Variation of the mixed-linker composition parameter (x) allows continuous control of n-butane, i-butane, butanol, and isobutanol diffusivities over 2-3 orders of magnitude and control of water and alcohol adsorption especially at low activities.