Sensing and Transport Properties of Hybrid Organic/Inorganic Devices

Over the past two decades, organic semiconductors played a growing part as active layers in several electronic systems such as sensors, field‑effect transistors or light emitting diodes to cite a few. In fact, organic materials offer a high versatility and flexibility. However, pure organic systems often lack stability and robustness, which can be overcome by combining them with inorganic scaffolds. In this work, a conducting polymer, polypyrrole (PPy) is employed to create new sensor elements based on the combination of both inorganic and organic layers. Electrical measurements, infrared spectroscopy and current sensing atomic force microscopy provides a better understanding of the polymer behavior upon immersion in aqueous solutions. The observed discharge in water leads to a straightforward application of the device as an in‑flow sensor for several acids like HCl, H2SO4 and H3PO4. The wide range of sensing concentrations as well as the low detection limit place the present detector among the best reported so far in the literature. In a further step to turn towards lab‑in‑a‑tube devices, tubular‑shaped‑integrated microelectrodes are developed by using the rolled‑up technology. As a proof of concept, the successful integration of PPy as an active layer and its use as a gas sensor for volatile organic compounds (VOCs) is demonstrated. Finally, by adapting the rolled‑up top electrodes, as developed by Bof Bufon et al. for self‑assembled monolayers (SAMs), thin PPy films (<50 nm) are vertically contacted and their electrical characteristics measured as a function of temperature and electric field. From the transport investigations, it is observed that an insulating‑to‑metallic transition occurs in the polymeric film by increasing the bias voltage. Other molecular layers like CuPc can be incorporated in these platforms, opening the way towards emerging organic devices

Efficacy and safety of baricitinib in hospitalized adults with severe or critical COVID-19 (Bari-SolidAct): a randomised, double-blind, placebo-controlled phase 3 trial

International audienceAbstract Background Baricitinib has shown efficacy in hospitalized patients with COVID-19, but no placebo-controlled trials have focused specifically on severe/critical COVID, including vaccinated participants. Methods Bari-SolidAct is a phase-3, multicentre, randomised, double-blind, placebo-controlled trial, enrolling participants from June 3, 2021 to March 7, 2022, stopped prematurely for external evidence. Patients with severe/critical COVID-19 were randomised to Baricitinib 4 mg once daily or placebo, added to standard of care. The primary endpoint was all-cause mortality within 60 days. Participants were remotely followed to day 90 for safety and patient related outcome measures. Results Two hundred ninety-nine patients were screened, 284 randomised, and 275 received study drug or placebo and were included in the modified intent-to-treat analyses (139 receiving baricitinib and 136 placebo). Median age was 60 (IQR 49–69) years, 77% were male and 35% had received at least one dose of SARS-CoV2 vaccine. There were 21 deaths at day 60 in each group, 15.1% in the baricitinib group and 15.4% in the placebo group (adjusted absolute difference and 95% CI − 0.1% [− 8·3 to 8·0]). In sensitivity analysis censoring observations after drug discontinuation or rescue therapy (tocilizumab/increased steroid dose), proportions of death were 5.8% versus 8.8% (− 3.2% [− 9.0 to 2.7]), respectively. There were 148 serious adverse events in 46 participants (33.1%) receiving baricitinib and 155 in 51 participants (37.5%) receiving placebo. In subgroup analyses, there was a potential interaction between vaccination status and treatment allocation on 60-day mortality. In a subsequent post hoc analysis there was a significant interaction between vaccination status and treatment allocation on the occurrence of serious adverse events, with more respiratory complications and severe infections in vaccinated participants treated with baricitinib. Vaccinated participants were on average 11 years older, with more comorbidities. Conclusion This clinical trial was prematurely stopped for external evidence and therefore underpowered to conclude on a potential survival benefit of baricitinib in severe/critical COVID-19. We observed a possible safety signal in vaccinated participants, who were older with more comorbidities. Although based on a post-hoc analysis, these findings warrant further investigation in other trials and real-world studies. Trial registration Bari-SolidAct is registered at NCT04891133 (registered May 18, 2021) and EUClinicalTrials.eu ( 2022-500385-99-00 )