A Conformable Organic Electronic Device for Monitoring Epithelial Integrity at the Air Liquid Interface

Abstract

Air liquid interfaced (ALI) epithelial barriers are essential for homeostatic functions such as nutrient transport and immunological protection. Dysfunction of such barriers are implicated in a variety of autoimmune and inflammatory disorders and, as such, sensors capable of monitoring barrier health are integral for disease modelling, diagnostics and drug screening applications. To date, gold‐standard electrical methods for detecting barrier resistance require rigid electrodes bathed in an electrolyte, which limits compatibility with biological architectures and is non‐physiological for ALI. This work presents a flexible all‐planar electronic device capable of monitoring barrier formation and perturbations in human respiratory and intestinal cells at ALI. By interrogating patient samples with electrochemical impedance spectroscopy and simple equivalent circuit models, disease‐specific and patient‐specific signatures are uncovered. Device readouts are validated against commercially available chopstick electrodes and show greater conformability, sensitivity and biocompatibility. The effect of electrode size on sensing efficiency is investigated and a cut‐off sensing area is established, which is one order of magnitude smaller than previously reported. This work provides the first steps in creating a physiologically relevant sensor capable of mapping local and real‐time changes of epithelial barrier function at ALI, which will have broad applications in toxicology and drug screening applications.

Electrochemical Investigation of PEDOT:PSS/Graphene Aging in Artificial Sweat

“…Various equivalent circuits have been proposed for the analysis of PEDOT:PSS-based layers, ranging from the simplest serial RC circuit [ 21 , 38 ], Randles circuit, R s ( C dl ( R ct W )) [ 2 , 7 , 39 ], to significantly more complex ones involving multiple RC blocks and Warburg impedance ( W ) [ 2 , 8 ]. The choice of an equivalent circuit is significantly influenced by the substrates used and additives to the conducting polymer.…”