METHODS FOR TREATING BIOFILMS
Existing biofilms on a range of surfaces, including previously implanted medical devices and human skin, can be treated via application of an acidic liquid which has an effective solute concentration of from 0.3 to 1.4 Osm/L and a pH of from 3.7 to 4.2.
1 : A method for in situ treatment of an implanted medical device having thereon a biofilm, said method comprising contacting said biofilm with a liquid composition comprising solvent and solute components and having a calculated effective solute concentration of from 0.3 to 1.4 Osm/L and a pH of from 3.7 to 4.2 for a time sufficient to reduce surface or skin bioburden resulting from said biofilm.
2 : The method of claim 1 wherein said composition has a calculated effective solute concentration of from 350 to 590 mOsm/L.
3 : The method of claim 2 wherein said composition has a calculated effective solute concentration of 525±50 mOsm/L.
4 : The method of claim 1 wherein said composition has a calculated effective solute concentration of from 450 to 680 mOsm/L.
5 : The method of claim 1 wherein said composition has a pH of from 3.85 to 4.05.
6 : The method of claim 5 wherein said pH is 3.95±0.05.
7 : The method claim 1 wherein said solvent component consists of purified water.
8 : The method of claim 1 wherein said solute component comprises a buffer system and an ionic surfactant.
9 : The method of claim 8 wherein said buffer system consists of dissociation products of at least one carboxylic acid and at least one conjugate base of at least one carboxylic acid.
10 : The method of claim 9 wherein said buffer system comprises dissociation products of from 25 to 40 g/L citric acid and from 30 to 45 g/L of a citrate that comprises three alkali metal ions.
11 : The method of claim 8 wherein said composition comprises from 0.7 to 1.9 g/L ionic surfactant.
12 : The method of claim 11 wherein said ionic surfactant is an anionic surfactant.
13 : The method of claim 1 wherein said liquid composition is sterile.
14 . (canceled)
15 : The method of claim 1 wherein said solute component comprises a buffer system that comprises dissociation products of citric acid and at least one citrate.
16 : The method of claim 15 wherein said buffer system comprises dissociation products of from 30 to 38 g/L citric acid and of from 34 to 42 g/L of trisodium citrate.
17 : The method of claim 16 wherein the liquid composition has a pH gf 3.95±0.1.
18 : The method of claim 15 wherein said solute component further comprises from 0.75 to 1.25 g/L anionic surfactant.
19 . (canceled)
20 : The method of claim 1 wherein an implanted medical device having a biofilm thereon is the object of in situ treatment, said solute component of said composition comprising anionic surfactant.
21 : The method of claim 22 wherein said composition is applied to the skin of a patient suffering from atopic dermatitis or acne vulgaris.
22 : A method for treating human skin having thereon a biofilm, said method comprising contacting said biofilm with a liquid composition comprising solvent and solute components and having a calculated effective solute concentration of from 0.3 to 1.4 Osm/L and a pH of from 3.7 to 4.2 for a time sufficient to reduce surface or skin bioburden resulting from said biofilm.