US 4,528,268 AGranted

Apparatus and method for testing the sufficiency of sterilization

AssigneeH. W. Andersen Products Inc.

InventorsHarold W. Andersen, Charles H. Harrison

Life of this patent

Estimating the term…

Loading patent…

Abstract

Apparatus and method for testing the sufficiency of sterilization includes a test tube having a distal end in which a bacterial spore element is disposed. A sealed glass ampule containing a sterile liquid culture medium is disposed in the test tube and a plunger having a fenestration closed with a hydrophobic filter is fitted slidingly in the open end of the test tube. In use, the apparatus is exposed to sterilization, and thereafter the plunger is pushed down into the test tube to engage the ampule to slide the latter into engagement with an ampule-engaging means to thereby fracture or break the ampule so that the contents of the ampule are released into the test tube to contact the spore element, whereby the apparatus is then subjected to incubation, the sufficiency of the sterilization being thereby determined.

Claims21

Dependent claims

Apparatus for testing the sufficiency of sterilization comprising a test tube having an open end and a closed distal end, said test tube being adapted to receive a bacterial spore element, a sealed ampule containing a sterile liquid culture medium, said ampule being disposed in said test tube, engaging-breaking means in said test tube, and a hollow open-ended plunger fitted slidingly into the open end of said test tube into a position where said plunger is retained in said test tube and said ampule is disposed in said test tube in an unbroken state, said plunger having sealing means operable to seal off communication between the outside of said plunger and the inside of said test tube, a hydrophobic filter element sealing the distal fenestration of said plunger and allowing passage of air in and out of said test tube, said plunger being constructed and disposed such that upon increased insertion of the plunger into said test tube, said plunger engages said ampule to slide the latter into engagement with said engaging-breaking means in said test tube to thereby fracture or break the ampule so that its contents are released into said test tube to contact said spore element, said filter allowing oxygen to pass into said test tube while preventing bacteria from entering into said test tube, said filter also retaining the liquid in said test tube.

Apparatus for testing the sufficiency of sterilization comprising a test tube, said test tube being adapted to receive a bacterial spore element, a sealed ampule containing a sterile liquid culture medium, retaining means on the inside of said test tube for snugly and slidably retaining said ampule in said test tube, engaging-breaking means in said test tube, and a hollow open-ended plunger fitted slidingly into the open end of said test tube, said plunger having rib means providing communication between the inside and outside of said test tube and sealing ring means sealing off said communication, said plunger being insertable into said test tube into a position where said plunger is retained in said test tube and said ampule is disposed in said test tube in an unbroken state, a hydrophobic filter element sealing the distal fenestration of said plunger and allowing passage of air in and out of said test tube, said plunger being constructed and disposed such that upon insertion of said plunger into said test tube, said plunger engages said ampule to slide the latter into engagement with said engaging-breaking means to thereby break the ampule so that its contents are released into said test tube to contact said spore element, said filter allowing oxygen to pass into said test tube while preventing bacteria from entering into said test tube, said filter also retaining the liquid in said test tube.

A method of testing the sufficiency of sterilization comprising the steps of providing a sterile liquid culture medium and a source of microorganisms, containing said source of microorganisms in a test tube, containing said medium in a sealed ampule mounted slidably in said test tube, providing a hollow open-ended plunger for said test tube which fits slidably in said test tube and which has a fenestration closed with a hydrophobic filter which allows air to pass therethrough, exposing said apparatus including said source of microorganisms to a sterilant, manually forcing said plunger down into said test tube so that said ampule is broken and said medium contacts said source of microorganisms, placing the test tube in an incubator to effect incubation to ascertain whether a positive culture is obtained, admitting air into said test tube through said hollow open-ended plunger and said hydrophobic filter to allow the oxygen in the air to reach the growing organisms in the test tube during said incubation, said hydrophobic filter preventing random bacteria from entering the test tube during incubation, and said hydrophobic filter also precluding liquid from spilling from said test tube should said test tube be inadvertently tipped over during incubation.

Dependencies are inferred from the claim text.