Medical devices having antimicrobial coatings thereon
View Patent ↗The present invention provides a medical device, preferably a contact lens, which comprises an antimicrobial coating including at least one layer of polyquat of formula (I) or (II). The antimicrobial coating on the medical device of the invention has a high antimicrobial efficacy against microorganisms including Gram-positive and Gram-negative bacterial, a low toxicity, low coefficient of friction, and increased hydrophilicity while maintaining the desired bulk properties such as oxygen permeability and ion permeability of lens material. Such lenses are useful as extended-wear contact lenses. In addition, the invention provides a method for making a medical device, preferably a contact lens, having an antimicrobial coating thereon.
1. A medical device, comprising a core material and an antimicrobial surface coating, wherein said antimicrobial surface coating is an LbL coating obtained by using a layer-by-layer deposition technique and comprises at least one polyanionic-polyquat bilayer composed of one layer of a polyanionic material and one layer of the polyquat of formula (1),
wherein R 1 , R 2 , R 3 and R 4 , independently of one another, are C 1 -C 10 hydrocarbon radicals, wherein A and B, independently of one another, are n-alkylene groups having 3 to 15 carbon atoms or n-alkylene groups having 3 to 15 carbon atoms and one or more hydroxyl groups, wherein the index y is a number from about 10 to 500, wherein X is chlorine, bromine, or iodine, wherein said antimicrobial surface coating imparts to said medical device the following surface properties:
(a) a low coefficient of friction with a averaged value of less than 1.55, and
(b) hydrophilicity characterized by having an averaged contact angle of less than 80 degree, wherein the value of the averaged contact angle is obtained by averaging measurements of at least 3 individual medical devices, and using Sessile Drop test method.
wherein the polyanionic material is selected from the group consisting of polyacrylic acid, polymethacrylic acid, and mixtures thereof.
2. A medical device of claim 1 , wherein said antimicrobial surface coating comprises one or more layers of polyquat of formula (I) in which one of A and B is hexamethylene radical (—CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 —) and the respective other one is an n-alkylene group having 6 to 12 carbon atoms.
3. A medical device of claim 1 , wherein the medical device is an ophthalmic lens.
4. An ophthalmic lens of claim 3 , wherein the ophthalmic lens is a contact lens.
5. A contact lens of claim 4 , wherein the antimicrobial surface coating comprises a capping layer of the polyquat of formula (I).
6. A contact lens of claim 4 , wherein the antimicrobial surface coating further comprises at least one polyelectrolyte bilayer which is composed of one layer of the polyanionic material and one layer of a polycationic material.
7. A contact lens of claim 6 , wherein the polycationic material is selected from the group consisting of poly(allylamine hydrochloride), poly(ethyleneimine), poly(vynylbenzyltriamethylamine), polyaniline, polypyrrole, poly(pyridinium acetylene), and mixtures thereof.
8. A contact lens of claim 4 , wherein said core material is a hydrogel.
9. A contact lens of claim 8 , wherein said hydrogel is a siloxane-containing polymer.