Packaging Solutions
A packaging system for the storage of a hydrogel contact lens employs an aqueous solution including hydroxypropyl methylcellulose.
1 . A method comprising:
(a) immersing a contact lens in a package with an aqueous solution comprising hydroxypropyl methylcellulose, wherein the solution has an osmolality of at least about 200 mOsm/kg and a pH in the range of 6 to 8;
(b) sealing the solution and the contact lens within the package; and
(c) sterilizing the packaged solution and device.
2 . The method of claim 1 , wherein the contact lens is a silicone hydrogel contact lens.
3 . The method of claim 1 , wherein the contact lens is a Group III or IV contact lens.
4 . The method of claim 1 , wherein the solution has a viscosity in the range of 0.5 to 5 cps.
5 . The method of claim 1 , wherein the solution has an osmolality in the range of 250 to 400 mOsm/kg, a pH in the range of 7.0 to 7.5, and a viscosity in the range of 1 to 3 cps.
6 . The method of claim 1 , wherein the concentration of hydroxypropyl methylcellulose is 0.05 to 5 weight percent.
7 . The method of claim 1 , wherein the concentration of hydroxypropyl methylcellulose is 0.1 to 0.4 weight percent.
8 . The method of claim 1 , wherein the hydroxypropyl methylcellulose has a viscosity (at 20 oC and at 2 weight % in water) of no greater than 50 cps.
9 . The method of claim 1 , wherein the hydroxypropyl methylcellulose has a viscosity (at 20 oC and at 2 weight % in water) of no greater than 25 cps.
10 . The method of claim 1 , wherein the solution comprises a buffer and NaCl.
11 . The method of claim 10 , wherein the solution comprises a borate buffer.
12 . The method of claim 1 , including hermetically sealing the contact lens and the solution in the package and heat sterilizing the package contents.
13 . The method of claim 1 , wherein the solution does not contain an effective disinfecting amount of a disinfecting agent or a germicide compound.
14 . A combination comprising a contact lens and an aqueous solution in a sealed container, wherein the solution comprises hydroxypropyl methylcellulose and the solution has an osmolality of at least about 200 mOsm/kg and a pH in the range of 6 to 8.
15 . The combination of claim 14 , wherein the contact lens is a silicone hydrogel contact lens.
16 . The combination of claim 14 , wherein the solution consists essentially of hydroxypropyl methylcellulose, a borate buffer and NaCl.
17 . The combination of claim 14 , wherein the solution consists of hydroxypropyl methylcellulose, a buffer, NaCl, water, and an optional chelating agent.
18 . The combination of claim 14 , wherein the solution consists of: 0.05 to 0.5 weight percent hydroxypropyl methylcellulose; 0.05 to 2.5 weight percent buffer; 0.01 to 2.5 weight percent NaCl; 0 to 1 weight percent chelating agent; and water.
19 . The combination of claim 15 , wherein the solution comprises: 0.05 to 0.5 weight percent hydroxypropyl methylcellulose; 0.05 to 2.5 weight percent buffer; and 0.01 to 2.5 weight percent NaCl; and the solution has an osmolality in the range of 250 to 400 mOsm/kg, a pH in the range of 7.0 to 7.5, and a viscosity in the range of 1 to 3 cps.
20 . The combination of claim 19 , wherein the hydroxypropyl methylcellulose has a viscosity (at 20 oC and at 2 weight % in water) of no greater than 25 cps.