Conversion of nitrogen dioxide (NO
Inhalation of low levels of nitric oxide can rapidly and safely decrease pulmonary hypertension in mammals. A nitric oxide delivery system that converts nitrogen dioxide to nitric oxide employs a surface-active material, such as silica gel, coated with an aqueous solution of antioxidant, such as ascorbic acid.
1. A method of delivering nitric oxide to a human comprising converting nitrogen dioxide to nitric oxide by fluidly communicating a gas flow including nitrogen dioxide to a receptacle including an inlet, an outlet, and a surface-active material comprising silica coated with an aqueous solution of an antioxidant, wherein the antioxidant includes ascorbic acid or a variant of vitamin E, wherein the inlet is configured to receive the gas flow and fluidly communicate the gas flow to the outlet through the surface-active material such that nitrogen dioxide in the gas flow is converted to nitric oxide.
2. The method of claim 1 wherein the surface-active material is saturated with the aqueous solution of the antioxidant.
3. The method of claim 1 wherein the surface-active material comprises a substrate that retains water.
4. The method of claim 1 wherein the variant of vitamin E includes alpha tocopherol or gamma tocopherol.
5. The method of claim 4 where the silica gel is 35 to 70 sized mesh.
6. The method of claim 1 wherein the receptacle comprises a cartridge.
7. The method of claim 1 wherein the antioxidant comprises ascorbic acid.
8. The method of claim 1 wherein the receptacle is at ambient temperature.
9. The method of claim 1 wherein the surface-active material is prepared using a solution of ascorbic acid in water.
10. The method of claim 9 wherein the surface-active material is prepared using a 20% solution of ascorbic acid in water.
11. The method of claim 9 wherein the surface-active material is prepared using a 25% solution of ascorbic acid in water.
12. The method of claim 9 wherein the surface-active material is prepared using a 30% solution of ascorbic acid in water.
13. The method of claim 1 wherein the surface-active material is prepared by soaking the surface-active material in a solution of ascorbic acid in water and air drying the surface-active material before inserting the surface-active material into the receptacle.
14. The method of claim 1 wherein the surface-active material is prepared by soaking the surface-active material in a solution of ascorbic acid in water and drying the surface-active material with a gas before inserting the surface-active material into the receptacle.
15. The method of claim 1 wherein the antioxidant comprises alpha tocopherol or gamma tocopherol.
16. The method of claim 1 wherein the receptacle includes screen and glass wool adjacent to both the inlet and the outlet.
17. The method of claim 1 wherein the screen and glass wool is soaked in the aqueous solution of antioxidant before being inserted in the receptacle.