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Structure-based targeting of fluorescent dyes is essential for their use as imaging agents for disease diagnosis. Here, we describe the development of the benzoquinolizinium compound Medical fluorophore 1 (MF1) as a novel biomedical imaging agent that allows the visualization of inflammation by virtue of its unique chemical structure. Lipopolysaccharide treatment stimulated the uptake of MF1 by bone marrow-derived macrophages, with no adverse effects on cell proliferation. In vivo fluorescence lifetime imaging revealed the accumulation of MF1 in carrageenan-induced acute inflammatory lesions in mice, which peaked at 6 h. MF1-based imaging also allowed monitoring of the response to the anti-inflammatory drugs dexamethasone and sulfasalazine. Thus, MF1 can be used to diagnose diseases characterized by inflammation as well as treatment efficacy. [ABSTRACT FROM AUTHOR]

A hybrid electrode, PEDOT:PSS/Ag NW containing a non-ionic surfactant (Triton X-100), was developed to enhance the mechanical stability of the Ag NW electrode and used for flexible ECL displays. The resulting hybrid electrode exhibited an outstanding figure of merit value of 12.3 × 10−3Ω−1 and stable luminescence efficiency under the bending test. [ABSTRACT FROM AUTHOR]

Flexible multi-channel Si nanowire (NW) field-effect transistors (FETs) were investigated to determine the effect of the number of Si NWs. The Langmuir–Blodgett method was applied for the formation of well-aligned Si NW monolayers, and an ion-gel with a high dielectric constant was used as a gate insulator in a top-gate TFT structure to secure flexibility. Like typical nanoelectronic devices, the drain current changed with the number of Si NWs. However, unlike previous reports, the mobility of the multi-channel Si NW FETs increased from 42.8 to 124.6 cm2 V−1 s−1 as the number of Si NWs was increased from 1 to 58. To verify the feasibility of our approach, the electrical performance of the TFTs fabricated on a flexible polyimide (PI) substrate was analyzed in respect of the bending strain (0.08–1.51%) and bending cycle (up to 12 000 cycles). As the number of Si NWs was increased, the trade-off between electrical and mechanical properties during bending tests was confirmed, and the appropriate number of Si NWs was optimized for a flexible FET with excellent performance. [ABSTRACT FROM AUTHOR]

Work function modulation of electrode materials is a crucial factor for achieving superior performance in transparent and flexible device applications. In this work, aluminum-doped zinc-oxide nanoparticles (AZO NPs) with a low work function were introduced in single-walled carbon nanotube (SWCNT) transparent electrodes to achieve an Ohmic contact with an indium-oxide (In2O3) active layer. These SWCNT–AZO NP hybrid electrodes exhibited a low contact resistance with the solution-processed In2O3 active layer, due to the low work function of the AZO NPs physisorbed on the SWCNTs. The 50 nm thick SWCNT–AZO NP hybrid films showed a considerably low electrical resistance of 214.5 Ω sq−1, an optical transmittance of 82.1% and a work function of 4.57 eV. By using these materials as the source and drain electrodes, fully solution-processed In2O3 thin film transistors (TFTs) were fabricated, and they showed excellent device performance. Furthermore, the fully solution-processed flexible In2O3 TFTs with these SWCNT–AZO NP hybrid electrodes exhibited only a 2.02% decrease in the field effect mobility after 1000 cycles of repeated bending stress at a radius of curvature of 3 mm. [ABSTRACT FROM AUTHOR]

Herein, we propose an ionic liquid–polymer dielectric layer for flexible electronics reinforced by a chemical interaction between the polymer matrix (PVP) and the ionic liquid. Due to the robust structures of the cross-linked PVP matrix and hydrogen bonding between the ionic liquid and PVP, the ionic liquid–PVP (IL–PVP) layer exhibited a good mechanical strength when bending up to 1000 times and a stable thermal behaviour up to 300 °C. Furthermore, the IL–PVP dielectric layer showed a high capacitance value of ∼2 μF cm−2 and was operated well as a gate insulator for flexible ZnO thin film transistors with a linear field-effect mobility of ∼3.3 cm2 V−1 s−1 at a gate bias of 3 V. [ABSTRACT FROM AUTHOR]

A single-wall carbon nanotube–aluminium (SWCNT)–Al bilayer was developed as an electrode for a high-performance solution processable thin film transistor (TFT). The contact resistance was systematically lowered by inserting an Al layer between the SWCNTs and the indium oxide. The performance of the device was considerably enhanced by adopting the SWCNT–Al bilayer electrodes, because of the enlargement of the contact area of the electrodes and the formation of an Ohmic contact between the electrodes and the semiconductor. The TFT using the SWCNT–Al bilayer electrodes shows a threshold voltage of 0.45 V, a mobility of 4.50 cm2 V−1 s and an Ion/Ioff of 6.86 × 105. [ABSTRACT FROM AUTHOR]

An unprecedented organocatalytic enantioselective formal synthesis of bromopyrrole alkaloid natural products is reported. An organocatalytic aza-Michael addition using pyrroles as the N-centered nucleophile is utilized as the enantioselective step to construct the nitrogen-substituted stereogenic carbon center in bromopyrrole alkaloids in good yield and excellent enantioselectivity. The aza-Michael product is converted via lactamization using a Staudinger-type reductive cyclization to the key intermediate, which was previously used in the total synthesis of bromopyrrole alkaloid natural products.