Process and apparatus for dry sterilization of medical devices and materials

• US 6,342,187 B1
• Filed: 09/21/2000
• Issued: 01/29/2002
• Est. Priority Date: 02/25/1987
• Status: Expired due to Fees

• Current Assignee: Adir Jacob
• Original Assignee: Adir Jacob
• Inventors: Jacob, Adir, Wilder, Jonathan Allen
• Primary Examiner(s): Mayekar, Kishor
• Application Number:
  US09/666,913
• Time in Patent Office: 495 Days
• Field of Search: 422/186.29, 422/186.05, 422/22, 204/164
• US Class Current: 422/186.05
• CPC Class Codes: A61L 2/12 Microwaves
• CPC Class Codes: A61L 2/14 Plasma, i.e. ionised gases

Abstract

Articles which it is intended to sterilize are placed into a confined volume and are subjected to neutral species of an electrical discharge while maintaining the volume glowless and substantially field free by interposing a barrier between the articles and the discharge, the barrier being transparent to neutral species and opaque to charged species emanating from the discharge.

Claims

1. Plasma generating apparatus for sterilization of medical devices and materials, comprising

a chamber having an axial length, and comprising a gas tight chamber wall made of electrically conductive material, the chamber wall being adapted for connection to a reference potential;

a chamber door at one end of said chamber'"'"'s axial length, said chamber door defining an inner door surface, the inner door surface also being adapted for connection to a reference potential;

an electrically conductive electrode positioned within said chamber and defining an inner volume, said electrode having a generally similar cross section as said chamber and containing perforations along its length, essentially all of said perforations having a diameter of less than or equal to about 4 mm;

a source of RF voltage adapted for application between said electrode and said reference potential;

a shelf electrically insulated from said electrode and placed within its inner volume, said shelf configured for receiving sealed gas permeable sterilization containers holding medical devices and materials to be sterilized; and

means for evacuating the chamber to a pressure less than or equal to about 0.5 Torr;

wherein upon application of the RF voltage at about 0.5 Torr pressure, a plasma glow discharge occurs between said electrode and said chamber wall, while the volume inside the sterilization container remains free of plasma glow.

2. A method for sterilizing medical devices and materials within a plasma generating apparatus, comprising

providing a chamber having an axial length, and comprising a gas tight chamber wall made of electrically conductive material, said chamber wall being connected to a reference potential, said chamber further comprising a chamber door at one end of said chamber'"'"'s axial length and defining an inner door surface, said inner door surface also being connected to a reference potential, an electrically conductive electrode positioned within the chamber and defining an inner volume, said electrode having generally a similar cross section as the chamber and containing perforations along its length, essentially all of said perforations having a diameter of less than or equal to about 4 mm, and a shelf electrically insulated from the electrode and placed within the inner volume of said chamber, said shelf being configured for receiving sealed gas permeable sterilization containers holding medical devices and materials to be sterilized;

evacuating the chamber to a pressure less than or equal to about 0.5 Torr; and

applying an RF voltage between said electrode and said reference potential;

wherein upon application of the RF voltage at about 0.5 Torr pressure, a plasma glow discharge occurs between the electrode and the chamber wall, while the volume inside the sterilization container remains void of plasma glow.