S-nitrosothiol-generating skin dressings
The present disclosure relates to a skin dressing adapted, on activation, to generate one or more S-nitrosothiols by reaction between a thiol and a nitrite salt in the skin dressing for delivery of nitric oxide to a body site. The skin dressing comprises a source of Cu 2+ , Zn 2+ and/or Fe 2+ ions.
1. A skin dressing adapted, on activation, to generate one or more S-nitrosothiols by reaction between a thiol and a nitrite salt in the skin dressing, the skin dressing comprising:
a first component comprising the nitrite salt and a buffer with a pK a of from 4.5 to 7.0;
a second component comprising the thiol, wherein the second component is kept apart from the first component until activation; and
a source of Cu 2+ , Zn 2+ and/or Fe 2+ ions;
wherein the only component in the dressing that has a pK a of from 1.0 to 4.0 is the nitrite, and wherein the thiol is selected from the group consisting of 1-thioglycerol, 1-thioglucose, methyl-ester of cysteine, ethyl-ester of cysteine, glutathione, L-glutathione, cysteine, N-acetylcysteine, mercaptoethylamine, and 3-mercaptopropanoic acid.
2. The skin dressing of claim 1 , wherein the buffer has a pK a of from 5 to 6.
3. The skin dressing of claim 1 , wherein a pH of the first component is from 2 to 5.
4. The skin dressing of claim 1 , wherein a pH of the first component is from 3 to 4.
5. The skin dressing of claim 1 , wherein a pH of the second component is from 7 to 10.
6. The skin dressing of claim 5 , wherein a pH of the first component is from 3 to 4.
7. The skin dressing of claim 6 , wherein the buffer has a pK a of from 5 to 6.
8. The skin dressing of claim 1 , wherein the first and second components are amorphous.
9. The skin dressing of claim 1 , wherein the first component and/or the second component comprise a polymeric support.
10. The skin dressing of claim 9 , wherein the polymeric support comprises polyacrylic acid.
11. The skin dressing of claim 1 , wherein the first component comprises the source of Cu 2+ , Zn 2+ and/or Fe 2+ ions.
12. The skin dressing of claim 1 , wherein the nitrite salt includes at least one nitrite selected from the group consisting of sodium nitrite and potassium nitrite.
13. A skin dressing comprising:
a first component including a nitrite salt;
a second component including a thiol; and
a source of Cu 2+ , Zn 2+ and/or Fe 2+ ions;
wherein the skin dressing has a storage state in which the first component and the second component are separated, and an activated state in which the first component and the second component contact one another;
wherein the skin dressing is adapted, in the activated state, to generate one or more S-nitrosothiols by reaction between the nitrite salt of the first component and the thiol of the second component; and
wherein the only component in the dressing that has a pK a of from 1.0 to 4.0 is the nitrite, and wherein the thiol is selected from the group consisting of 1-thioglycerol, 1-thioglucose, methyl-ester of cysteine, ethyl-ester of cysteine, glutathione, L-glutathione, cysteine, N-acetylcysteine, mercaptoethylamine, and 3-mercaptopropanoic acid.
14. The skin dressing of claim 13 , wherein the first component includes a buffer with a pK a of from 4.5 to 7.0.
15. The skin dressing of claim 13 , wherein at least one of the first component and the second component includes the source of Cu 2+ , Zn 2+ and/or Fe 2+ ions.