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A green instrument-free approach to (bio)chemical analyses: cellulose acetate-based microwell plates as substitutes to plastic microwell plates. 

Alzheimer's disease (AD) has been consistently related to the formation of senile amyloid plaques mainly composed of amyloid β (Aβ) peptides. The toxicity of Aβ aggregates has been indicated to be responsible for AD pathology. One scenario to decrease Aβ toxicity is the development of effective inhibitors against Aβ amyloid formation. In this study, we investigate the effect of gallium nitride nanoparticles (GaN NPs) as inhibitors of Aβ40 amyloid formation using a combination of biophysical approaches. Our results show that the lag phase of Aβ40 aggregation kinetics is significantly retarded by GaN NPs in a concentration dependent manner, implying the activity of GaN NPs in interfering with the formation of the crucial nucleus during Aβ aggregation. Our results also show that GaN NPs can reduce the amyloid fibril elongation rate in the course of the aggregation kinetics. It is speculated that the high polarization characteristics of GaN NPs may provoke a strong interaction between the particles and Aβ40 peptide and in this way decrease self-association of the peptide monomers to form amyloids. 

The electrical characterization and ammonia vapor (NH₃) response of a p‐Si/n‐poly[benzimidazobenzophenanthroline] (n‐BBL) thin‐film junction diode are reported. The presence of a depletion layer at the n‐BBL/p‐Si interface is verifiedviacapacitance–voltage measurements, and the built‐in potential is ≈1.8 V. Using the standard diode equation for data analysis, the turn‐on voltage, rectification ratio, and ideality parameter are found to be 2 V, 16, and 6, respectively. The diode is also tested in the presence of NH₃vapor where it retained its asymmetricJ–Vbehavior with increased currents and an insignificant change in device parameters. NH₃is believed to interact with the adsorbed O₂⁻species on the n‐BBL surface liberating electrons that enhance the diode current. The response time, recovery time, and sensitivity of the diode are 65 s, 121 s, and 52%, respectively. The removal of the gas restores the diode characteristics to their near original shape making it reusable. The diode is also electrically characterized as a function of temperature and is found to retain its rectifying behavior down to 150 K. The rectifying and gas‐sensing features make the diode multifunctional, which expands the range of applications of this ladder‐type conducting polymer. 

CVD grown MoSe2 monolayers were electrically characterized at room temperature in a field effect transistor (FET) configuration using an ionic liquid (IL) as the gate dielectric. During the growth, instead of using MoO3 powder, ammonium heptamolybdate was used for better Mo control of the source and sodium cholate added for lager MoSe2 growth areas. In addition, a high specific capacitance (∼7 μF/cm2) IL was used as the gate dielectric to significantly reduce the operating voltage. The device exhibited ambipolar charge transport at low voltages with enhanced parameters during n- and p-FET operation. IL gating thins the Schottky barrier at the metal/semiconductor interface permitting efficient charge injection into the channel and reduces the effects of contact resistance on device performance. The large specific capacitance of the IL was also responsible for a much higher induced charge density compared to the standard SiO2 dielectric. The device was successfully tested as an inverter with a gain of ∼2. Using a common metal for contacts simplifies fabrication of this ambipolar device, and the possibility of radiative recombination of holes and electrons could further extend its use in low power optoelectronic applications. 

Abstract A poly(triaryl amine) thin film field effect transistor was investigated in air with ionic liquid (IL) gating for the first time. The transistor retained a high‐on/off ratio of ~700 and mobility of ~10⁻²cm²/V‐s. When compared to a transistor based on the conducting polymer polyaniline under similar operating conditions, it was found to exhibit superior performance. Significantly low‐operating voltages (±1 V) enhances the possibility of its use in organic electronics. The device was successfully tested for binary operation, and we demonstrate its suitability for use in low‐power consumption electronic circuits.