11 December 2020
Development of a colour-sensitive inkjet-printed pixelated artificial retina model and its study via an optoelectronic device
Around 300 million people worldwide are visually impaired. In recent years, photosensitive organic electronic materials have been shown to be a very promising tool for transducing light stimuli to non-functioning retinas. An international interdisciplinary team from four institutes developed a colour-sensitive artificial retina model using polymer semiconductors. These are processable as inks which enabled pixelatation by depositing each polymer dot by inkjet-printing. Three types of polymer semiconductors, with spectral absorbance curves emulating those of rods, and of cones which provide colour sensitivity, were deposited in a concentric layout simplifying the anatomical human retinal scheme. The team verified that the phototransduction process from the artificial retina to a biological electrolyte solution imitating extracellular fluids found in our tissues produced electrical signals compatible with those found in retinas through a novel closed sandwich-type optoelectronic device. Biocompatibility of the materials was also verified. The bio-hybrid device is compact, easy-to-handle, transportable, with controllable size and requires a small amount of bio-electrolyte thus permitting use of tools typically found in an electronic-engineering/physics/chemistry laboratory. The density of the artificial photoreceptors was ∼11000 pixels/cm2 and the corresponding spatial resolution was 267 dpi (dots per inch), with pixel diameters of 95 micrometres comparable to that of a human hair.
Results are published in “Colour‑sensitive conjugated polymer inkjet‑printed pixelated artificial retina model studied via a bio‑hybrid photovoltaic device” article in Scientific Reports at https://rdcu.be/cbQ6g
For more information see the press release and
