Intravitreally Injected Plasmonic Nanorods Activate Bipolar Cells with Patterned Near-Infrared Laser Projection.

Area of Science:

• Biomedical Engineering
• Neuroscience
• Ophthalmology

Background:

• Degenerative retinal diseases cause vision loss, necessitating prosthetic solutions.
• Current retinal prostheses have limitations like invasiveness, limited resolution, and interference with residual vision.
• Nanoparticle-based methods offer minimally invasive options but may use visible light.

Purpose of the Study:

• To develop a less invasive retinal prosthesis using gold nanorods (AuNRs) for vision restoration.
• To achieve precise neural activation via patterned near-infrared (NIR) light stimulation.
• To target bipolar cells for high-resolution visual restoration.

Main Methods:

• Intravitreal injection of anti-Thy1 antibody-conjugated AuNRs.
• Patterned NIR laser scanning (20 μm spot size) for photothermal stimulation.
• In vivo electrocorticogram (ECoG) recordings in wild-type and blind mice.

Main Results:

• Localized neuronal activation of bipolar cells via photothermal effect.
• Evoked ECoG responses in the visual cortex of both mouse models.
• No significant systemic toxicity or retinal damage observed.

Conclusions:

• This approach offers a precise, customizable, and less invasive method for vision restoration.
• The technique demonstrates potential for significant advancements in spatial resolution and broad applicability.
• Patterned NIR stimulation with AuNRs shows promise for treating blindness caused by retinal degeneration.