Patent ID: 11927512
Assignee: ALCON INC.
Field: Measurement (Instruments)
Classification: CPC B  G | IPC G

Claim 0:
1. A method for determining the thickness of coatings on the surfaces of contact lenses, comprising the steps of:
(a) obtaining a coated contact lens in fully hydrated state, wherein the coated contact lens comprises a lens body and a coating thereon, wherein the lens body comprises a non-silicone hydrogel material or a silicone hydrogel material, wherein the coating comprises a coating material having negatively-charged groups;
(b) selectively staining the coating over the lens body of the coated contact lens by immersing the coated contact lens in an aqueous solution of a fluorescently-labeled polycationic polymer for a time period of about 12 hours or less, wherein the aqueous solution comprises buffering agents in an amount for having a pH of from about 6.5 to about 8.0;
(c) orthogonally cutting the selectively-stained coated contact lens; and
(d) determining the thickness of the coating on the coated contact lens.