High-Tech and Nature-Made Nanocomposites and Their Applications in the Field of Sensors and Biosensors for Gas Detection

Abstract

Gas sensors have been object of increasing attention by the scientific community in recent years. For the development of the sensing element, two major trends seem to have appeared. On one hand, the possibility of creating complex structures at the nanoscale level has given rise to ever more sensitive sensors based on metal oxides and metal-polymer combinations. On the other hand, gas biosensors have started to be developed, thanks to their intrinsic ability to be selective for the target analyte. In this review, we analyze the recent progress in both areas and underline their strength, current problems, and future perspectives.

Keywords: bio-sniffers; biosensors; conductive polymers; enzymatic inhibition; enzymes; gas sensors; metal oxides; multi-enzyme cycle; nanomaterials; whole cells biosensors.

Figure 1

SEM images of the modified thin films developed ((A) and (B)), elemental analysis (C), and result obtained with the surface plasmon resonance (SPR) technique for the detection of formaldehyde (D). Reproduced from [13] with permission from Elsevier (License number 4927020376869).

Figure 2

SEM images reported in the work of Patil et al.: (a) polyaniline (PANI)–ZnO with 10% of camphor sulfonic acid (CSA); (b) PANI–ZnO with 20% CSA; (c) PANI–ZnO with 30% CSA; (d) PANI–ZnO with 40% CSA and (e) PANI–ZnO with 50% CSA. Reproduced from [53] with permission from Elsevier (License number 4930190716578).

Figure 3

An example of a sensor-based on olfactory cells (a) with a detail of cell interfacing with transducer (b) and circuitry involved (c). A broader scheme of the experiments is reported (d). Reproduced from [91] with permission from Elsevier (License number 4930191079175).

Figure 4

(A) Electrochemical and metal oxide semiconductor sensor used by Biosensor Srl to develop (B) multigas sensor array to detect and quantify NOx and acetic acid.