Light-induced charge generation in polymeric nanoparticles restores vision in advanced-stage retinitis pigmentosa rats

Abstract

Retinal dystrophies such as Retinitis pigmentosa are among the most prevalent causes of inherited legal blindness, for which treatments are in demand. Retinal prostheses have been developed to stimulate the inner retinal network that, initially spared by degeneration, deteriorates in the late stages of the disease. We recently reported that conjugated polymer nanoparticles persistently rescue visual activities after a single subretinal injection in the Royal College of Surgeons rat model of Retinitis pigmentosa. Here we demonstrate that conjugated polymer nanoparticles can reinstate physiological signals at the cortical level and visually driven activities when microinjected in 10-months-old Royal College of Surgeons rats bearing fully light-insensitive retinas. The extent of visual restoration positively correlates with the nanoparticle density and hybrid contacts with second-order retinal neurons. The results establish the functional role of organic photovoltaic nanoparticles in restoring visual activities in fully degenerate retinas with intense inner retina rewiring, a stage of the disease in which patients are subjected to prosthetic interventions.

Activity of Retinal Neurons Can Be Modulated by Tunable Near-Infrared Nanoparticle Sensors

“…As an optical neuromodulation technique, NINM is likely to preserve a high spatial resolution and can be projected directly through the cornea without the need for surgery, obviating the need for an invasive implant. Although subretinally injected nanoparticles have demonstrated robust retinal retention for up to 2–3 months postinjection, ,,, RGC targeting is likely to necessitate intravitreal injection, for which long-term retinal retention remains the subject of future work. Future work will also require a more exhaustive study of distinct RGC responses based on cell type and subtype in order to elucidate additional avenues for selective stimulation.…”

Photoactive Nanomaterials for Wireless Neural Biomimetics, Stimulation, and Regeneration

“…Light sensitivity and visual activities in old dystrophic animals can be restored to normal levels by forming the light-induced “hybrid synapses” of the retina. This is a useful way for retinal prosthesis construction at a retinitis pigmentosa advanced stage . It represents a promising method for the treatment of age-related degeneration and retinitis pigmentosa, with low invasiveness, long-lasting effect and high spatial resolution.…”

“…This is a useful way for retinal prosthesis construction at a retinitis pigmentosa advanced stage. 105 It represents a promising method for the treatment of age-related degeneration and retinitis pigmentosa, with low invasiveness, long-lasting effect and high spatial resolution. In this case, how the potential difference affects the electrolyte solution around P3HT NPs should be further explored.…”

Resonant Enhancement of Polymer–Cell Optostimulation by a Plasmonic Metasurface

“…Further improvements in the device performances have been obtained using nanostructured P3HT. 8 , 9 Overall, the enhancement of such photodriven phenomena, which ultimately depend on the light absorption capability of the active layer, would certainly improve device functionality and enable their use under low-light illumination.…”

“…Here, a layer of P3HT deposited over a poly­(3,4-ethylenedioxythiophene):polystyrenesulfonate (PEDOT:PSS) layer absorbs the incoming light and interacts with the neighboring cells, inducing a bioelectric response in neurons via a stimulation mechanism that likely involves both photothermal and photocapacitive phenomena occurring at the abiotic/biotic interface. Further improvements in the device performances have been obtained using nanostructured P3HT. , Overall, the enhancement of such photodriven phenomena, which ultimately depend on the light absorption capability of the active layer, would certainly improve device functionality and enable their use under low-light illumination.…”