South Korean chemists have developed a hydrogel material for contact lenses that self-heals from scratches after just an hour at room temperature under ultraviolet (UV) light.1

While this kind of self-healing has been demonstrated before, it has required temperatures much higher than room temperature. The ability to induce the repair using ordinary equipment at home would signal a step towards a new generation of contact lenses.

“During contact lens wear, microscratches caused by blinking or routine cleaning can scatter light and cause glare, while also providing sites for protein or microbial adhesion, ultimately compromising ocular health,” the researchers wrote.

“Moreover, surfaces roughened by scratches and microcracks facilitate the adhesion and accumulation of proteins, increasing wearer discomfort and the risk of infection.”

The researchers created the hydrogel, which was then coated with another polymer to reduce bacterial adhesion and improve resistance to surface scratches. When a damaged hydrogel was exposed to UV light (365 nanometers in wavelength) at room temperature for one hour, the energy from the light induced a healing process known as disulfide exchange. In tests, this healing process was highly efficient, resulting in a near-seamless repair.

According to the researchers, the repair process can be repeated and could even be conducted using at-home UV lamps, such as those used for curing gel nail polish.

As well as self-healing, the new material demonstrated water retention on a par with current soft lenses, as well as excellent scratch resistance. Further stability testing is required.

Reference available at mivision.com.au.