Method for determining coating thickness on coated contact lenses

Patent metadata

Field	Value
Publication number	US-11927512-B2
Application number	US-202017087983-A
Country	US
Kind code	B2
Filing date	Nov 3, 2020
Priority date	Nov 5, 2019
Publication date	Mar 12, 2024
Grant date	Mar 12, 2024

Abstract

The invention provides a method for imaging and thickness determination of coatings on coated contact lenses. The method comprises selectively staining a negatively-charged-groups-containing coating over the lens body of a coated contact lens by immersing the coated contact lens in an aqueous solution comprising a fluorescently-labeled polycationic polymer and having a pH of from about 6.5 to 8.0; orthogonally cutting the selectively-stained coated contact lens; and determining the thickness of the coating on the coated contact lens. In addition, the invention provides a method for selecting a candidate coating material comprising negatively charged groups for applying a coating with a desired thickness onto silicone hydrogel contact lenses and for optimizing a coating process for producing coated silicone hydrogel contact lenses with a desired thickness coating thereon.

First claim

What is claimed is:

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.

2. The method of claim 1 , wherein the non-silicone hydrogel material or the silicone hydrogel material is free of negatively-charged groups.

3. The method of claim 2 , wherein the lens body comprises a silicone hydrogel material.

4. The method of claim 3 , wherein the negatively charged groups of the coating material are carboxyl groups.

5. The method of claim 4 , wherein the fluorescently-labeled polycationic polymer has a number average molecular weight of greater than 1500 Daltons and at least 50% by mole of monomeric units each having a positively-charged groups at a pH from about 6.5 to about 8.0.

6. The method of claim 5 , wherein the fluorescently-labeled polycationic polymer is a fluorescently-labeled polycationic polypeptide which comprises at least 50% by mole of one or more positively charges amino acid units selected from the group consisting of lysine, arginine, histine, 2,3-diaminopropionic acid, and combinations thereof.

Assignees

• Alcon Inc

Inventors

• Chang Yuan
• Zheng Ying
• Ge Junhao
• Zhang Steve Yun
• Sentell Karen Belinda
• Dou Jinbo

Classifications

• G01N1/30 Primary

  Staining; Impregnating {; Fixation; Dehydration; Multistep processes for preparing samples of tissue, cell or nucleic acid material and the like for analysis} · CPC title

• G01N1/04

  in the solid state, e.g. by cutting · CPC title

• G01N21/77

  by observing the effect on a chemical indicator · CPC title

• G02B1/043

  Contact lenses · CPC title

• G01N2001/302

  Stain compositions · CPC title