Rigid gas permeable contact lens deposition measured via radiolabeled proteins

Image courtesy of Adobe Stock/Valeri Luzina

At the 2023 Global Specialty Lens Symposium, Centre for Ocular Research and Education’s (CORE) Biosciences group presented a scientific post on an investigation of protein deposits rigid gas permeable (RGP) contact lens deposition via a novel method: Incorporating radiolabeled lysozyme into an artificial tear solution, which allows researchers to determine on-lens protein through radioactive counts.¹

Investigators soaked 7 common RGP lens materials in the radioactive artificial tear solution for 16 hours, then exposed to a 3% one-step hydrogen peroxide (OSP) care solution for 8 hours to evaluate cleaning ability.

The deposits were minimal without use of a cleaning solution. The deposits ranged from 1.2 ± 0.2 μg to 3.2 ± 0.7 μg per RGP lens. After 30 alternating incubating and cleaning cycles with OSP solution, the amount of radioactive lysozyme on the RGP lenses reduced significantly when compared to using phosphate buffered saline. With the OSP solution, the remaining lysozyme on cleaned lenses ranged from 1.3 ± 0.1 μg to 2.5 ± 0.1 μg per lens.

“Renewed interest in RGP lenses around the world, sparked by the rise in their use for myopia management, has subsequently increased the desire for more advanced research. CORE has built a reputation for discovering new ways to precisely assess ophthalmic devices and pharmaceuticals, and this radiolabeling technique has strong potential for other applications,” Alex Hui, OD, PhD, FAAO, head of Biosciences at CORE, said in a press release.

The unique approach was previously used to study soft contact lens deposition in the past, but it was the first time radiolabeled lysozyme was used to investigate protein deposits on RGP contact lenses.

The investigation, conducted by the CORE Biosciences group, was initially presented as a scientific poster at the 2023 Global Specialty Lens Symposium: "The impact of RGP care solutions on ISO measured lens parameters and the protein deposition on RGP lenses when managed with a hydrogen peroxide care solution," Hui, et al. The study was supported by funding from CooperVision.

CORE’s Biosciences group delves into important research regarding ocular surface and biomaterials, especially contact lenses. In 2022, CORE broadened its specialty contact lens investigations to examine design optimization for orthokeratology, scleral lens physiological performance, and the effect of scleral lenses on ocular surface disease and dry eye.

Reference

CORE Biosciences group uses radiolabeled proteins to study RGP contact lens deposition. Press release. Centre for Ocular Research and Education. February 13, 2023. Accessed February 13, 2023.