Blind mice see again with gold-powered breakthrough, human trials to follow

Yahoo

21-04-2025

In a promising breakthrough for treating vision loss, scientists at Brown University have developed a potential new way to restore sight using gold nanoparticles and infrared light—no surgery or genetic engineering required.
The study shows that injecting gold nanoparticles into the eye and stimulating them with infrared lasers can activate retinal cells and partially restore vision in mice with retinal degenerative conditions.
"This is a new type of retinal prosthesis that has the potential to restore vision lost to retinal degeneration without requiring any kind of complicated surgery or genetic modification," said Jiarui Nie, the lead researcher.
"We believe this technique could potentially transform treatment paradigms for retinal degenerative conditions."
The group conducted the technique in isolated mouse retinas and living mice with retinal lesions. They projected laser patterns, which were designed as shapes, onto the treated retinas and recorded their visual activity in the brain's visual cortex regions to determine whether the visual activity corresponds with electrical activity—the expectation that the nanoparticle stimulation was, indeed, providing visual information to be processed.
Most notably, no inflammatory or toxic effects were found, indicating that the nanoparticles did not produce significant harm and damage to the retina was none. Moreover, the particles showed no signs of degradation months after being placed in the retina.
As opposed to surgery, "an intravitreal injection is one of the simplest procedures in ophthalmology," Nie said.
In humans, the scientists imagine a smart goggle or glasses system with potential real-world applications. These goggles would host cameras alongside a low-power infrared laser capable of transforming real-world visuals into accurately designed light patterns.
Laser activation would stimulate retinal nanoparticles, thus enabling the brain to 'see' images without functioning photoreceptors.
This concept is similar to earlier FDA-approved systems involving electrode implants, but with several key advantages. It is a minimally invasive procedure—only an eye injection is needed, not surgery. Second, unlike limited electrode arrays, nanoparticles can cover the entire retina. Additionally, it preserves residual vision using infrared, which doesn't interfere with remaining natural eyesight.
Though still in early stages, the findings open the door to a new class of non-surgical, light-based visual prosthetics. Before human use, more studies and eventual clinical trials are needed, but the initial results are promising.
"We showed that the nanoparticles can stay in the retina for months with no major toxicity," Nie said of the research. "And we showed that they can successfully stimulate the visual system. That's very encouraging for future applications."
The research has been published in ACS Nano.