Near-Infrared Tandem Organic Photodiodes for Future Application in Artificial Retinal Implants.
Giulio SimoneDario Di Carlo RasiXander de VriesGaël H L HeintgesStefan C J MeskersRené A J JanssenGerwin H GelinckPublished in: Advanced materials (Deerfield Beach, Fla.) (2018)
Photovoltaic retinal prostheses show great potential to restore sight in patients suffering from degenerative eye diseases by electrical stimulation of the surviving neurons in the retinal network. Herein, organic photodiodes (OPDs) sensitive to near-infrared (NIR) light are evaluated as photovoltaic pixels for future application in retinal prostheses. Single-junction and tandem OPDs are compared. In the latter, two nominally identical single-junction cells are processed on top of each other, effectively doubling the open-circuit voltage (V OC ). Both single-junction and tandem OPD micropixels can deliver the required charge to stimulate neurons under pulsed NIR light at physiologically safe intensities when connected to stimulating microelectrodes in a physiological saline solution. However, only tandem OPD pixels can cover the entire charge per pulse neural stimulation window due to their higher V OC (≈1.4 V). This demonstrates the viability of high-resolution retinal prostheses based on flexible OPD arrays.
Keyphrases
- optical coherence tomography
- diabetic retinopathy
- optic nerve
- high resolution
- solar cells
- end stage renal disease
- photodynamic therapy
- spinal cord
- blood pressure
- newly diagnosed
- induced apoptosis
- ejection fraction
- spinal cord injury
- chronic kidney disease
- current status
- minimally invasive
- cell death
- cell cycle arrest
- oxidative stress
- fluorescence imaging
- patient reported outcomes
- endoplasmic reticulum stress
- cell proliferation
- drug delivery
- high density