Abstract
Miniaturized gas sensors and biosensors based on nanostructured sensing elements have attracted considerable interest because these nanostructured materials can be used to significantly improve sensor sensitivity and the response time. We report here on a generic, reversible sensing platform based on hybrid nanofilms. Thin ordered Langmuir-Blodgett (LB) films built of fluorene derivatives were used as effective gas sensors for both oxidative and reductive analytes. A novel immobilization method based on thin LB films as a matrix has been developed for construction of sensing protein layers. Biomolecules can often be incorporated into and immobilized on Langmuir-Blodgett films using adsorption methods or by covalent immobilization of proteins. The sensor sensitisation was achieved by an amphiphilic N-alkyl-bis(thiophene)arylenes admixed into the film. The interlaced derivative was expected to facilitate the electron transfer, thereby enhancing the sensor sensitivity. The results suggest that this may be very promising approach for exploring the interactions between proteins and high throughput detection of phenol derivatives in wastewater.
Highlights
A variety of different chemical sensors based on conducting molecules can be used for gaseous or liquid analytes
Conductometric electronic noses based on conducting structures have been applied to the detection of odours connected with fires [1], aromatic hydrocarbons [2], pollutants in water [3,4] or for analysis of wine [5]
The changes in electrical conductivity can be exploited for a number of chemical or gas sensor applications, as known from literature, for example, in the case of a chemiresistor device built of dithiolene metal complexes [23] and an optical sensor for detection of gases such as nitrogen oxides built of a highly polarisable organic material (Polysiloxane I) [24]
Summary
A variety of different chemical sensors based on conducting molecules can be used for gaseous or liquid analytes. Chemical reactions lead to changes in the doping levels of conducting materials and alter their physical properties like resistance. Electron donating gases like NH3 reduce and dedope conducting materials by electrochemical removal of the counterion, which leads to an increase in resistance. This process rarely goes to completion due to limitations arising from the slow diffusion of counterions from the solid polymer matrix. Fluorene-based conjugated polymers have emerged as a very promising class of materials for use in electronic sensor devices because of their thermal stability, good solubility, and facile functionalization at the C-9 position of fluorene.
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
