Cold gas sterilization process

• US 4,169,124 A
• Filed: 09/26/1977
• Issued: 09/25/1979
• Est. Priority Date: 09/26/1977
• Status: Expired due to Term

• Current Assignee: Allegiance Corporation (Cardinal Health, Inc.)
• Original Assignee: Moore-Perk Corporation
• Inventors: Wardle, Michael D., Forstrom, Richard J.
• Primary Examiner(s): Richman, Barry S.
• Application Number:
  US05/836,665
• Time in Patent Office: 729 Days
• Field of Search: 21/57, 21/58, 424/130, 422/28, 422/32, 422/33, 422/29
• US Class Current: 422/33
• CPC Class Codes: A01N 59/00 Biocides, pest repellants or attractants, or plant growth regulators containing elements or inorganic compounds
• CPC Class Codes: A61L 12/084 in a gaseous state
• CPC Class Codes: A61L 12/124 Hydrogen peroxide; Peroxy compounds
• CPC Class Codes: A61L 2/20 Gaseous substances, e.g. vapours

Abstract

A "cold" gas sterilization process that operates at temperatures below 80° C. in a temperature range that is generally considered nonsporicidal. The process is capable of sterilizing with gaseous hydrogen peroxide at extremely low concentrations in a gas phase, such as 0.5 mg/L. The widely used process of "cold" sterilizing with ethylene oxide is typically run at a gas concentration of 630 mg/L and 55° C. Apparatus is also disclosed for use of this process in "cold" sterilization of contact lenses.

Claims

1. A method of "cold" gas sterilization which comprises:

surrounding an article to be sterilized with hydrogen peroxide gas having a concentration of less than 75 mg/L; and

maintaining such gas in contact with such article at temperatures below 80°

C. until such article is sterile, whereupon sterility of said article is established and including the step of maintaining said article in a sterile condition protected from recontamination until use.

2. A method as set forth in claim 1, wherein the gas is maintained at temperatures above approximately 20°

C.

3. A method as set forth in claim 1, wherein the gas in maintained in contact with such article for a period greater than 60 seconds.

4. A method of "cold" sterilizing an article not suited for total liquid submersion, comprising the steps of:

encasing said article in a chamber;

surrounding the article in the chamber with hydrogen peroxide gas having a concentration of less than 75 mg/L; and

maintaining such gas in contact with the article at temperatures below 80°

C. until such article is sterile, whereupon sterility of said article is established and including the step of maintaining said article in a sterile condition protected from recontamination until use.

5. A method as set forth in claim 5, wherein the method includes the step of evacuating the chamber.

6. A method as set forth in claim 5, wherein the article is encased in a sealed sterilizer tank.

7. A method as set forth in claim 5, wherein the article is encased in a package with at least one portion of the package being pervious to passage of hydrogen peroxide gas, but impervious to microbial passage.

8. A method of "cold" gas sterilization which comprises:

surrounding an article to be sterilized with hydrogen peroxide gas having a concentration of less than 75 mg/L and at a pressure of less than atmospheric; and

maintaining said gas under such conditions in contact with such article at temperatures below 80°

C. until such article is sterile, whereupon sterility of said article is established and including the step of maintaining said article in a sterile condition protected from recontamination until use.

9. A method as set forth in claim 8, wherein the gas is under a negative pressure of at least 15 inches of Hg.

10. A method of "cold" gas sterilization which comprises:

surrounding an article to be sterilized with hydrogen peroxide gas having a concentration of 0.1 to 50 mg/L; and

maintaining such gas in contact with the article for a period of greater than 60 seconds and at temperatures of from 45°

C. to 65°

C. until such article is sterile, whereupon sterility of said article is established and including the step of maintaining said article in a sterile condition protected from recontamination until use.