Biomimetic sensing layer based on electrospun conductive polymer webs

Abstract

The aim of the present study is to combine a bio-inspired nanofibrous artificial epithelium to the electronic nose (e-nose) principles. The sensing device set up was an electronic nose consisting of an array of 9 micro-chemoresistors (Cr-Au, 3×3) coated with electrospun nanofibrous structures. These were comprised of doped polyemeraldine base blended with 3 different polymers: polyethylene oxide, polyvinilpyrrolidone and polystyrene, which acted as carriers for the conducting polymer and were the major responsible of the features of each fibrous overlay (electrical parameters, selectivity and sensitivity ranges). The two sensing strategies here adopted and compared consisted in the use of 2 different textural coatings: a single- and a double-overlay, where the double-overlay resulting from overdeposition of 2 different polymer blends. Such e-nose included a plurality of nanofibres whose electrical parameters were at the same time depending on each polymer exposure to analytes (NO(2), NH(3)) and on the spatial distribution of the interlacing fibres. The morphology of the coating arrangements of this novel e-nose was investigated by scanning electron microscopy (SEM) and its sensor responses were processed by multicomponent data analyses (PCA and PLS) reporting encouraging results for detection and recognition of analytes at ppb levels.

A Comparative Study of Multifunctional Coatings Based on Electrospun Fibers with Incorporated ZnO Nanoparticles

“…This pitting current increase rate (v pitting ) is determined as the slope of the polarization curve in the region between the pitting potential (E p ) and the potential at which the current cutoff value of 2.5 mA is reached (E cutoff ). A straight-line approximation approach can be used to estimate this value [32]:…”

“…The samples were immersed for 30 min in the NaCl electrolyte in order to ensure steady state before conducting the electrochemical experiments. Tafel polarization measurements were obtained by scanning the electrode potential from −150 to +150 mV at a scan rate of 1.5 mV·s −1 , and the corrosion protection efficiency for the coatings (η) was calculated by the following equation [31,32]:…”

Functional nanofibers in food processing

“…Some promising results have been obtained with fully integrated chemiresistor microchipsbased on electrospun polymer fi bers (Zampetti et al ., 2011), namely with chemoresistive carbon black-polymer composite sensors, owing to their broad response to diverse volatile organic compounds as detection elements in the electronic nose systems, or based on polyaniline as a conductive polymer due to its thermal stability and sensing performances. Some promising results have been obtained with fully integrated chemiresistor microchipsbased on electrospun polymer fi bers (Zampetti et al ., 2011), namely with chemoresistive carbon black-polymer composite sensors, owing to their broad response to diverse volatile organic compounds as detection elements in the electronic nose systems, or based on polyaniline as a conductive polymer due to its thermal stability and sensing performances.…”

Implementation of Olfactory Bulb Glomerular-Layer Computations in a Digital Neurosynaptic Core

“…Presently, most artificial olfaction research is focused on sensor technology; for example, metal oxide transistors (Gonzalez-Jimenez et al, 2011), polymer-immobilized fluorescent dyes (Dickinson et al, 1996), metalloporphyrins (Paolesse et al, 2008), conductive polymer arrays (Beccherelli et al, 2010) and fiber webs (Zampetti et al, 2011), and even carbon nanotube transistors functionalized for diversity with single-strand DNA (Staii et al, 2005) or by coupling to G-protein coupled receptors (Goldsmith et al, 2011) have been developed to try and increase the sensitivity and diversity of primary analyte detection while reducing the costs and practical difficulties of deployment (Hierlemann and Gutierrez-Osuna, 2008). Somewhat less attention, however, has been paid to the subsequent analysis of these response patterns in artificial systems.…”