Process for making biomedical devices
A process for treating a medical device involves: (a) treating a silicon-containing biomedical device with an organic solvent that swells the device, and treating the device with a hydrophilic, monomeric material; and (b) exposing the biomedical device and the hydrophilic, monomeric material to heat or light radiation to polymerize the hydrophilic, monomeric material.
1 . A process for treating a medical device comprising, sequentially:
(a) treating a silicon-containing biomedical device with an organic solvent that swells the device, and treating the device with a hydrophilic, monomeric material; and
(b) exposing the biomedical device and the hydrophilic, monomeric material to heat or light radiation to polymerize the hydrophilic, monomeric material.
2 . The process of claim 1 , further comprising removing the organic solvent, whereby polymerized hydrophilic material remains retained in the device.
3 . The process of claim 1 , wherein in step (a), the device is treated simultaneously with a solution containing the organic solvent and the hydrophilic, monomeric material.
4 . The process of claim 1 , comprising, sequentially:
(a) treating a silicon-containing biomedical device with an organic solvent that swells the device;
(a′) treating the device with a hydrophilic, monomeric material; and
(b) exposing the biomedical device and the hydrophilic, monomeric material to heat or light radiation to polymerize the hydrophilic, monomeric material.
5 . The process of claim 4 , further comprising removing the organic solvent, whereby polymerized hydrophilic material remains retained in the device.
6 . The process of claim 1 , wherein step (b) includes autoclaving the device containing the hydrophilic, monomeric material.
7 . The process of claim 4 , wherein step (a) includes soaking the device in a solution comprising organic solvent, and step (a′) includes soaking the device in an aqueous solution comprising the hydrophilic, monomeric material.
8 . The process of claim 1 , wherein in step (a), the device swells in volume by at least 30%.
9 . The process of claim 1 , wherein in step (a), the device swells in volume by at least 50%.
10 . The process of claim 1 , wherein in step (a), the device swells in volume by at least 100%.
11 . The process of claim 1 , wherein the device shrinks in volume as the hydrophilic, monomeric material replaces the organic solvent in the device.
12 . The process of claim 1 , wherein the device is a contact lens.
13 . The process of claim 1 , wherein the device is a silicone hydrogel contact lens.
14 . The process of claim 1 , wherein the hydrophilic, monomeric material includes at least one member selected from the group consisting of N-vinylpyrrolidone, ethylenically unsaturated PVP, ethylenically unsaturated PVA, ethylenically unsaturated PAA, and ethylenically unsaturated PEO.
15 . The process of claim 1 , wherein the hydrophilic, monomeric material includes (meth)acrylate functionality.
16 . The process of claim 15 , wherein the hydrophilic, monomeric material includes (meth)acrylated PVP.
17 . The process of claim 1 , wherein step (a) includes soaking the device in an aqueous solution comprising the hydrophilic, monomeric material and an initiator.
18 . The process of claim 1 , wherein step (a) includes soaking the device in isopropanol, ethanol, or an aqueous mixture thereof.
19 . The process of claim 1 , wherein the hydrophilic, monomeric material has an Mn of at least 500.
20 . The process of claim 1 , wherein the hydrophilic, monomeric material has an Mn of at least 1000.
21 . The process of claim 1 , wherein the hydrophilic, monomeric material has an Mn of at least 3000.
22 . The process of claim 1 , comprising, sequentially:
(a) soaking a silicon-containing contact lens in a solution including an organic solvent that swells the device in volume by at least 30%;
(b) soaking the contact lens in an aqueous solution including a hydrophilic, monomeric material, whereby the hydrophilic, monomeric material replaces the organic solvent in the lens and shrinks the lens in volume; and
(c) exposing the contact lens with the hydrophilic, monomeric material absorbed therein to heat or light radiation to polymerize the hydrophilic, monomeric material.
23 . The process of claim 22 , wherein step (b) is repeated with aqueous solutions including sequentially lower amounts of the hydrophilic monomeric material.