The most common strategies to control electrical activity in living cells are based on electrical or chemical stimulation. However, in recent years, techniques relying on optical stimuli are emerging as promising alternatives with peculiar advantages, particularly for the high degree of temporal and spatial resolution that can be achieved. Here we describe the technique of cell stimulation by polymer photo-excitation (CSP), which takes advantage of the unique optoelectronic properties of the interface between organic semiconducting thin films and an ionic liquid environment. Due to their intrinsic bio-affinity with biological systems, conjugated polymers have been demonstrated as functional substrates for the growth of different types of cellular systems. CSP exploits their ability to generate electrical stimuli following photoexcitation. In particular, we demonstrate that thin films of poly(3-hexylthiophene) (P3HT) are able to elicit electrical activity in different types of cells, from primary neurons to cellular lines. An interesting result is that the stimulation is equally effective with films obtained by blending the donor polymer with an electron acceptor, but also with single component P3HT layers; this allows us to shed light on the actual photoexcitation mechanism, which is based on a capacitive coupling of the active interface with the cellular membrane, as corroborated by further physico-chemical analysis. Other developments of the technique with important consequences for neuroscientific experimentation will also be presented. These results open the way to a new generation of neuronal communication and photo-manipulation tools.
Bio-organic interfaces for cellular photo-excitation
MARTINO, NICOLA;LANZANI, GUGLIELMO
2013-01-01
Abstract
The most common strategies to control electrical activity in living cells are based on electrical or chemical stimulation. However, in recent years, techniques relying on optical stimuli are emerging as promising alternatives with peculiar advantages, particularly for the high degree of temporal and spatial resolution that can be achieved. Here we describe the technique of cell stimulation by polymer photo-excitation (CSP), which takes advantage of the unique optoelectronic properties of the interface between organic semiconducting thin films and an ionic liquid environment. Due to their intrinsic bio-affinity with biological systems, conjugated polymers have been demonstrated as functional substrates for the growth of different types of cellular systems. CSP exploits their ability to generate electrical stimuli following photoexcitation. In particular, we demonstrate that thin films of poly(3-hexylthiophene) (P3HT) are able to elicit electrical activity in different types of cells, from primary neurons to cellular lines. An interesting result is that the stimulation is equally effective with films obtained by blending the donor polymer with an electron acceptor, but also with single component P3HT layers; this allows us to shed light on the actual photoexcitation mechanism, which is based on a capacitive coupling of the active interface with the cellular membrane, as corroborated by further physico-chemical analysis. Other developments of the technique with important consequences for neuroscientific experimentation will also be presented. These results open the way to a new generation of neuronal communication and photo-manipulation tools.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
