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New technologies for developing second generation retinal prostheses


Inherited or age-dependent retinal dystrophies such as Retinitis pigmentosa (RP) and macular degeneration (MD) are among the most prevalent causes of blindness. Despite enormous efforts, no established pharmacological treatment to prevent or cure photoreceptor degeneration has been identified. Given the relative survival of the inner retina, attempts have been made to restore vision with optogenetics or with retinal neuroprostheses to allow light-dependent stimulation of the inner retinal network. While microelectrode and photovoltaic devices based on inorganic technologies have been proposed and in many cases implanted in RP patients, a new generation of prosthetics based on organic molecules, such as organic photoswitches and conjugated polymers, is demonstrating an unexpected potential for visual rescue and intimate interactions with functioning tissue. Organic devices are starting a new era of tissue electronics, in which light-sensitive molecules and live tissues integrate and tightly interact, producing a new ecosystem of organic prosthetics and intelligent biotic/abiotic interfaces. In addition to the retina, the applications of these interfaces might be extended in the future to other biomedical fields.

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The work was supported by the EU project FP7-PEOPLE-212-ITN 316832 “OLIMPIA”, Telethon - Italy GGP12033 and GGP14022; Fondazione Cariplo ONIRIS 2013–0738; Compagnia di San Paolo ID 4191; Italian Ministry of Health RF-2013-02358313. The support of Ra.Mo. Foundation (Milano, Italy) and Rare Partners srl (Milano, Italy) is also acknowledged.

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The authors declare that they do not have any competing financial interests in relation to the work described.

Correspondence to Fabio Benfenati.

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Fig. 1: Rehabilitating strategies to rescue vision in degenerative blindness.
Fig. 2: Conjugated polymers as light-sensitive neural interfaces.