Organic Bioelectronics for In Vitro Systems

Abstract

Bioelectronics have made strides in improving clinical diagnostics and precision medicine. The potential of bioelectronics for bidirectional interfacing with biology through continuous, label-free monitoring on one side and precise control of biological activity on the other has extended their application scope to in vitro systems. The advent of microfluidics and the considerable advances in reliability and complexity of in vitro models promise to eventually significantly reduce or replace animal studies, currently the gold standard in drug discovery and toxicology testing. Bioelectronics are anticipated to play a major role in this transition offering a much needed technology to push forward the drug discovery paradigm. Organic electronic materials, notably conjugated polymers, having demonstrated technological maturity in fields such as solar cells and light emitting diodes given their outstanding characteristics and versatility in processing, are the obvious route forward for bioelectronics due to their biomimetic nature, among other merits. This review highlights the advances in conjugated polymers for interfacing with biological tissue in vitro, aiming ultimately to develop next generation in vitro systems. We showcase in vitro interfacing across multiple length scales, involving biological models of varying complexity, from cell components to complex 3D cell cultures. The state of the art, the possibilities, and the challenges of conjugated polymers toward clinical translation of in vitro systems are also discussed throughout.

AC amplification gain in organic electrochemical transistors for impedance-based single cell sensors

“…1,2 The interest is motivated by the possibility to combine electrochemical transduction mechanisms known from metallic electrodes with the intrinsic ampli cation properties of a transistor structure. 3 The ampli cation is highly wanted to improve signal to noise ratio in challenging sensor applications aiming for instance at biochemical detection in complex mixtures 4 or single cell bioelectronic monitoring. 5 Signi cant progress on this concept has been made by the introduction of organic or carbon-based semiconducting materials with high stability in water such as carbon nanotubes, 6,7 graphene, 8,9 or organic semiconductors.…”

“…24,3 A second, emerging class of biosensors that takes advantage of OECT ampli cation regards impedance based sensors for monitoring cellular adhesion and cell layer barrier properties as quanti ed by the transepithelial electrical resistance (TEER). 25,4 Monitoring such cellular properties is of importance in studies of wound healing, cancer development, toxicity assays or recognition processes in the immune system. 25 Impedance based biosensors quantify the ionic current that passes through a cellular layer when an AC voltage is applied.…”

3D Organic Bioelectronics for Monitoring In Vitro Stem Cell Cultures

“…Considering these properties, PEDOT:PSS-based scaffolds have come to the fore as multifunctional biomaterials with tailor-made properties allowing the development of smart bioelectronic interfaces for in vitro models. 23 Organic bioelectronic interfaces for in vitro 3D stem cell cultures e can be customized to mimic accurately the micro-environment required for stem cell growth. For example, Iandolo et al developed composite PEDOT:PSS/collagen scaffolds with highly elastic mechanical properties that supported "soft" neural crest-derived stem cell culture.…”

“…22 Both GOPS and PEGDE render PEDOT:PSS water-stable via similar mechanisms — a reaction of the epoxy rings moiety present in their structures with the weakly nucleophilic PSS - . 23 Importantly, the choice of cross-linker impacts the electrochemical, 24 surface topography, 21 and mechanical properties 25 of PEDOT:PSS structures. Considering these properties, PEDOT:PSS-based scaffolds have come to the fore as multifunctional biomaterials with tailor-made properties allowing the development of smart bioelectronic interfaces for in vitro models.…”

“…Considering these properties, PEDOT:PSS-based scaffolds have come to the fore as multifunctional biomaterials with tailor-made properties allowing the development of smart bioelectronic interfaces for in vitro models. 23…”