Claims for Patent: 11,383,059

Summary for Patent: 11,383,059

Title:	Conversion of nitrogen dioxide (NO.sub.2) to nitric oxide (NO)
Abstract:	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.
Inventor(s):	Rounbehler; David P. (Lexington, MA), Fine; David H. (Cocoa Beach, FL)
Assignee:	VERO Biotech Inc. (Atlanta, GA)
Application Number:	17/459,058
Patent Claims:	1. A method, comprising: conveying a nitrogen dioxide-containing gas from a tankless gas source that contains dinitrogen tetroxide to a cartridge; and passing the nitrogen dioxide-containing gas through the cartridge to remove the nitrogen dioxide, producing a nitric oxide-containing gas. 2. The method of claim 1, wherein the cartridge includes a reducing agent configured to react with nitrogen dioxide to produce nitric oxide. 3. The method of claim 1, wherein the cartridge includes a substrate coated with a reducing agent, the method further comprises: flowing the nitrogen dioxide-containing gas over the substrate such that the reducing agent converts nitrogen dioxide in the nitrogen dioxide-containing gas to nitric oxide. 4. The method of claim 2, further comprising delivering the nitric oxide-containing gas to a patient. 5. The method of claim 3, further comprising delivering the nitric oxide-containing gas to a patient. 6. The method of claim 1, further comprising delivering the nitric oxide-containing gas to a patient. 7. A method, comprising: conveying a nitrogen dioxide-containing gas to a cartridge; and passing the nitrogen dioxide-containing gas through the cartridge, the cartridge including at least one of vitamin C or vitamin E configured to react with nitrogen dioxide to remove the nitrogen dioxide and produce a nitric oxide-containing gas. 8. The method of claim 7, further comprising delivering the nitric oxide-containing gas to a patient. 9. A method, comprising: conveying a nitrogen dioxide-containing gas to a cartridge; and passing the nitrogen dioxide-containing gas through the cartridge, the cartridge including silica gel wetted with ascorbic acid such that the nitrogen dioxide-containing gas flows over the silica gel and such that the ascorbic acid reacts with nitrogen dioxide to produce a nitric oxide-containing gas. 10. The method of claim 9, wherein: the silica gel is porous and has a mesh size between 35 and 70. 11. The method of claim 9, further comprising delivering the nitric oxide-containing gas to a patient. 12. The method of claim 10, further comprising delivering the nitric oxide-containing gas to a patient. 13. A method, comprising: conveying a nitrogen dioxide-containing gas to a cartridge; passing the nitrogen dioxide-containing gas through the cartridge to remove the nitrogen dioxide, producing a nitric oxide-containing gas; mixing the nitric oxide-containing gas with an oxygen-containing gas; and delivering the nitric oxide-containing gas to a patient after mixing the nitric oxide-containing gas and the oxygen-containing gas. 14. The method of claim 13, wherein the nitric oxide-containing gas is supplied to a ventilator prior to being delivered to the patient. 15. The method of claim 13, further comprising delivering the nitric oxide-containing gas to a flexible bag prior to delivering the nitric-oxide containing gas to the patient such that a constant supply of nitric oxide can be delivered to the patient during inhalation. 16. The method of claim 13, wherein the nitric oxide is delivered to the patient to treat pulmonary hypertension. 17. The method of claim 13, wherein the patient is a newborn and the nitric oxide is delivered to treat persistent pulmonary hypertension. 18. The method of claim 13, wherein the nitric oxide is delivered to the patient to treat bronchopulmonary dysplasia. 19. The method of claim 13, wherein the patient is a cardiac surgery patient. 20. A method, comprising: conveying a nitrogen dioxide-containing gas from an unpressurized tankless gas source to a cartridge; and passing the nitrogen dioxide-containing gas through the cartridge to remove the nitrogen dioxide, producing a nitric oxide-containing gas. 21. The method of claim 20, further comprising delivering the nitric oxide-containing gas to a patient. 22. A method, comprising: conveying a nitrogen dioxide-containing gas to a cartridge; passing the nitrogen dioxide-containing gas through the cartridge to remove the nitrogen dioxide, producing a nitric oxide-containing gas; measuring a concentration of nitrogen dioxide in the nitric oxide-containing gas before the nitric oxide-containing gas is delivered to a patient; and generating an alarm when a concentration of nitrogen dioxide in the nitric-oxide containing gas exceeds a threshold. 23. A method, comprising: conveying a nitrogen dioxide-containing gas to a cartridge; and passing the nitrogen dioxide-containing gas through the cartridge, the cartridge including a nontoxic reducing agent configured to react with nitrogen dioxide to produce a nitric oxide-containing gas. 24. The method of claim 23, further comprising delivering the nitric oxide-containing gas to a patient. 25. A method, comprising: conveying a nitrogen dioxide-containing gas to a cartridge; and passing the nitrogen dioxide-containing gas through the cartridge, the cartridge including a reducing agent configured to react with nitrogen dioxide to produce nitric oxide, removing all nitrogen dioxide from nitrogen dioxide-containing gas and producing a nitric oxide-containing gas. 26. The method of claim 25, further comprising delivering the nitric oxide-containing gas to a patient.