The systemic toxicity of intravitreally injected gold nanorods in mice: Effects of size, surface conjugation, and post-injection period.

Gold nanorods (AuNRs) are promising for remote neuronal activation via photothermal effects, but their systemic toxicity when delivered ocularly is unclear. We assessed the systemic safety of intravitreally injected AuNRs in mice over 32 days, testing three formulations: 25-nm diameter Thy-1 conjugated AuNRs (default), 10-nm diameter Thy-1 conjugated AuNRs (effect of size), and 25-nm diameter bare AuNRs (effect of surface chemistry). Thy-1 conjugation aimed to target retinal neurons specifically.

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

Retinal prostheses aim to restore vision in individuals affected by degenerative conditions, such as age-related macular degeneration and retinitis pigmentosa. Traditional approaches, including implantable electrode arrays and optogenetics, often require invasive surgery or genetic modification and face limitations in spatial resolution and visual field size. While emerging nanoparticle-based methods offer minimally invasive solutions, some of them rely on intense visible light, which may interfere with residual vision.