RESUMO
Nuclear factor-κB (NF-κB) signaling is classified into the canonical and noncanonical pathways. We describe in this chapter the methods used to study the noncanonical pathway, including derivation of primary cells, pathway stimulation, and immunoblotting.
Assuntos
NF-kappa B/metabolismo , Transdução de Sinais , Peptídeos e Proteínas Associados a Receptores de Fatores de Necrose Tumoral/metabolismo , Animais , Linfócitos B/metabolismo , Western Blotting , Técnicas de Cultura de Células , Ativação Enzimática , Fibroblastos/metabolismo , Separação Imunomagnética/métodos , Macrófagos/metabolismo , Camundongos , NF-kappa B/química , Cultura Primária de Células , Ligação Proteica , Transporte ProteicoRESUMO
We investigate the relationship between the charge carrier type in organic thin film transistors (OTFTs) and molecular energy levels. We examine a series of functionalized acenes that collectively have their HOMOs range from -4.9 eV to -5.6 eV and LUMOs range from -2.8 eV to -3.7 eV, as measured by cyclic voltammetry. Placed together, these 20 molecules allow us to chart the transition from OTFTs that display only hole transport, to ambipolar, to solely electron transport. Specifically, we note that for octadecyltrimethoxysilane (OTS) treated substrates, with top contact gold electrodes, electron injection and transport occurs when the LUMO < -3.15 eV, while hole injection and transport ceases when the HOMO < -5.6 eV. Ambipolar transport prevails when molecules have HOMO/ LUMO levels within the aforementioned range. This is seen across channel lengths ranging from 50-150 microm and using only gold as electrodes. This empirical plot is the first time such a detailed study has been made on the onset of charge injection and transport for a class of organic semiconductors. It provides guidelines for future molecular design.
RESUMO
We present a high performance, ambipolar organic field-effect transistor composed of a single material. Ambipolar molecules are rare, and they can enable low-power complementary-like circuits. This low band gap, asymmetric linear acene contains electron-withdrawing fluorine atoms, which lower the molecular orbital energies, allowing the injection of electrons. While hole and electron mobilities of up to 0.071 and 0.37 cm2/V.s, respectively, are reported on devices measured in nitrogen, hole mobilities of up to 0.12 cm2/V.s were found in ambient, with electron transport quenched. These devices were fabricated on octadecyltrimethoxysilane-treated surfaces at a substrate temperature of 60 degrees C.
