Organic thin-film transistor sensors have been recently attracting the attention of the plastic electronics community for their potential exploitation in novel sensing platforms. Specificity and sensitivity are however still open issues: in this respect chiral discrimination-being a scientific and technological achievement in itself--is indeed one of the most challenging sensor bench-tests. So far, conducting-polymer solid-state chiral detection has been carried out at part-per-thousand concentration levels. Here, a novel chiral bilayer organic thin-film transistor gas sensor--comprising an outermost layer with built-in enantioselective properties-is demonstrated to show field-effect amplified sensitivity that enables differential detection of optical isomers in the tens-of-parts-per-million concentration range. The ad-hoc-designed organic semiconductor endowed with chiral side groups, the bilayer structure and the thin-film transistor transducer provide a significant step forward in the development of a high-performance and versatile sensing platform compatible with flexible organic electronic technologies.
Photosynthesis is responsible for the photochemical conversion of light into the chemical energy that fuels the planet Earth. The photochemical core of this process in all photosynthetic organisms is a transmembrane protein called the reaction center. In purple photosynthetic bacteria a simple version of this photoenzyme catalyzes the reduction of a quinone molecule, accompanied by the uptake of two protons from the cytoplasm. This results in the establishment of a proton concentration gradient across the lipid membrane, which can be ultimately harnessed to synthesize ATP. Herein we show that synthetic protocells, based on giant lipid vesicles embedding an oriented population of reaction centers, are capable of generating a photoinduced proton gradient across the membrane. Under continuous illumination, the protocells generate a gradient of 0.061 pH units per min, equivalent to a proton motive force of 3.6 mV⋅min Remarkably, the facile reconstitution of the photosynthetic reaction center in the artificial lipid membrane, obtained by the droplet transfer method, paves the way for the construction of novel and more functional protocells for synthetic biology.
Self-assembled monolayers (SAMs) derived of 4-methoxy-terphenyl-3'',5''-dimethanethiol (TPDMT) and 4-methoxyterphenyl-4''-methanethiol (TPMT) have been prepared by chemisorption from solution onto gold thin films and nanoparticles. The SAMs have been characterized by spectroscopic ellipsometry, Raman spectroscopy and atomic force microscopy to determine their optical properties, namely the refractive index and extinction coefficient, in an extended spectral range of 0.75-6.5 eV. From the analysis of the optical data, information on SAMs structural organization has been inferred. Comparison of SAMs generated from the above aromatic thiols to well-known SAMs generated from the alkanethiol dodecanethiol revealed that the former aromatic SAMs are densely packed and highly vertically oriented, with a slightly higher packing density and a absence of molecular inclination in TPMT/Au. The thermal behavior of SAMs has also been monitored using ellipsometry in the temperature range 25-500 degrees C. Gold nanoparticles functionalized by the same aromatic thiols have also been discussed for surface enhanced Raman spectroscopy applications. This study represents a step forward tailoring the optical and thermal behavior of surfaces as well as nanoparticles.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.