Soft transparent graphene contact lens electrodes for conformal full-cornea recording of electroretinogram

Abstract

Visual electrophysiology measurements are important for ophthalmic diagnostic testing. Electrodes with combined optical transparency and softness are highly desirable, and sometimes indispensable for many ocular electrophysiology measurements. Here we report the fabrication of soft graphene contact lens electrodes (GRACEs) with broad-spectrum optical transparency, and their application in conformal, full-cornea recording of electroretinography (ERG) from cynomolgus monkeys. The GRACEs give higher signal amplitude than conventional ERG electrodes in recordings of various full-field ERG responses. High-quality topographic mapping of multifocal ERG under simultaneous fundus monitoring is realized. A conformal and tight interface between the GRACEs and cornea is revealed. Neither corneal irritation nor abnormal behavior of the animals is observed after ERG measurements with GRACEs. Furthermore, spatially resolved ERG recordings on rabbits with graphene multi-electrode array reveal a stronger signal at the central cornea than the periphery. These results demonstrate the unique capabilities of the graphene-based electrodes for in vivo visual electrophysiology studies.

Electronic Contact Lens: A Platform for Wireless Health Monitoring Applications

“…In other words, the four‐coil ICPT receiver side contains two more coils in separate layers compared with the two‐coil system. For electronic contact lenses, the two‐coil coupling ICPT is generally applied and can achieve flexible adjustment by tuning the coil geometry or matching components to meet the resonant frequency with a high transfer efficiency . For electronic contact lens antenna design, the uppermost mission is to transfer power without impeding vision, where the leading component is the pupil unit with a maximum 8 mm diameter.…”

Full activation pattern mapping by simultaneous deep brain stimulation and fMRI with graphene fiber electrodes

“…In this work, we report on a full and unbiased activation pattern mapping by DBS-fMRI with graphene fiber (GF) microelectrodes in a Parkinson's disease (PD) rat model. Graphene films have been utilized in various kinds of neural electrodes [15][16][17] , due to the unique electrical and optical properties. Here, we show that microelectrodes made from GFs exhibit the combined advantages of high charge-injection-capacity, stimulation stability, and MRI compatibility, which were not achievable by other electrodes.…”

Contact Lens Technology: From Fundamentals to Applications

“…Glucose binding induced a local volumetric increase, leading to a change in the Bragg diffraction. Graphene films were also used in contact lenses for various applications . An example of device for full‐corneal electroretinagram (ERG) recording is shown in Figure b .…”

“…Graphene films were also used in contact lenses for various applications . An example of device for full‐corneal electroretinagram (ERG) recording is shown in Figure b . The device consisted on a contact lens‐shaped parylene covered with a graphene layer on the concave side.…”