US20010039030A1 - Test device and method - Google Patents

Test device and method Download PDF

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Publication number
US20010039030A1
US20010039030A1 US09/052,303 US5230398A US2001039030A1 US 20010039030 A1 US20010039030 A1 US 20010039030A1 US 5230398 A US5230398 A US 5230398A US 2001039030 A1 US2001039030 A1 US 2001039030A1
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Prior art keywords
vessel
filter
inlet
liquid
syringe
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US09/052,303
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US6406879B2 (en
Inventor
Phillip Richard James
Richard Mark Bancroft
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Albert Browne Ltd
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Albert Browne Ltd
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Assigned to ALBERT BROWNE LIMITED reassignment ALBERT BROWNE LIMITED ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: JAMES, PHILLIP RICHARD, BANCROFT, RICHARD M.
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    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
    • A61L2/00—Methods or apparatus for disinfecting or sterilising materials or objects other than foodstuffs or contact lenses; Accessories therefor
    • A61L2/26—Accessories or devices or components used for biocidal treatment
    • A61L2/28—Devices for testing the effectiveness or completeness of sterilisation, e.g. indicators which change colour
    • C—CHEMISTRY; METALLURGY
    • C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12Q—MEASURING OR TESTING PROCESSES INVOLVING ENZYMES, NUCLEIC ACIDS OR MICROORGANISMS; COMPOSITIONS OR TEST PAPERS THEREFOR; PROCESSES OF PREPARING SUCH COMPOSITIONS; CONDITION-RESPONSIVE CONTROL IN MICROBIOLOGICAL OR ENZYMOLOGICAL PROCESSES
    • C12Q1/00—Measuring or testing processes involving enzymes, nucleic acids or microorganisms; Compositions therefor; Processes of preparing such compositions
    • C12Q1/02—Measuring or testing processes involving enzymes, nucleic acids or microorganisms; Compositions therefor; Processes of preparing such compositions involving viable microorganisms
    • C12Q1/22—Testing for sterility conditions

Definitions

  • This invention relates to a test device and method, in particular to a device and method for testing the biocidal efficacy of a liquid sterilant.
  • a test device for assessing the biocidal efficacy of a liquid comprises a vessel, means for introducing a predetermined volume of the liquid into the vessel via an inlet, and a porous filter interposed between the inlet and the vessel, wherein the vessel contains a predetermined quantity of biologically active organisms and the filter has a pore size effective to retain said organisms.
  • a method for assessing the biocidal efficacy of a liquid comprises
  • the device and method of the invention are advantageous primarily in that they enable testing of the biocidal activity of a liquid without the risk of contamination of the liquid with organisms utilised in the test procedure.
  • the vessel takes the form of a syringe.
  • the syringe plunger is used to draw up the predetermined volume of liquid and subsequently to expel the liquid and to draw up the culture medium.
  • the filter is preferably housed in a filter unit attached to the syringe. Both the syringe and the filter unit are preferably disposable.
  • the syringe is preferably of the disposable polyethylene or polypropylene type, equipped with a luer lock hub, generally with a capacity not exceeding ten millilitres.
  • the filter unit is preferably of the disposable sealed unit type, in which the housing may consist of polyethylene, polyvinyl chloride, polypropylene, polystyrene or similar polymers.
  • the housing preferably possesses a luer lock inlet.
  • the filter unit preferably contains a filter membrane, most preferably in disc form.
  • the membrane may consist of cellulose esters, polytetrafluoroethylene, polyvinylidene difluoride, nylon, polycarbonate or any other suitable polymer, or glass fibre material.
  • the membrane may be pre-treated so as to create hydrophilic and hydrophobic regions.
  • Polytetrafluoroethylene is a currently preferred membrane material.
  • the predetermined quantity of biologically active organisms is deposited on the filter, on the side of the filter connected to the syringe.
  • the organisms may be deposited on the membrane by a number of methods, including passing a suspension of organisms through the membrane, or depositing a suspension of organisms, in a volatile solvent, on the membrane and allowing the solvent to evaporate.
  • the method of the invention may comprise time delays between steps b) and c), and/or between steps d) and e).
  • one or more washing steps eg comprising introduction and removal of an appropriate rinsing agent, eg water, may take place between steps c) and d).
  • the step of ascertaining whether growth of biologically active organisms has taken place in the culture medium may comprise visual inspection, eg for the presence of turbidity.
  • the method and device of the invention may be utilised in connection with any form of biologically active organism which is conventionally killed using a liquid sterilant.
  • biologically active organism which is conventionally killed using a liquid sterilant.
  • One example is bacterial spores.
  • a device for testing the efficacy of a sterilant liquid is generally designated 1 and comprises a disposable clear plastics syringe 2 with a plunger 3 .
  • the syringe 2 has a nozzle 4 which is fixed in a corresponding luer lock neck 5 of a filter unit 6 .
  • the filter unit 6 is also disposable and of clear plastics material, and takes the form of a hollow disc.
  • the unit 6 comprises upper and lower (as viewed in the drawing) halves 6 a , 6 b which are joined at their adjoining peripheries and which sandwich a disc 7 of porous membrane material between them.
  • the lower half 6 b has a central open spigot 8 on which a spout 9 is fitted.
  • the upper (as viewed in the drawing) surface of the membrane disc 7 is inoculated with a known quantity of bacterial spores.
  • test sterilant is drawn into the device 1 (ie through the inoculated membrane 7 connected by luer lock to the syringe 2 ) by raising the plunger 3 , and is allowed to remain in the device for the required sterilization time. At the end of this period, the sterilant is ejected from the device 1 by depressing the plunger 3 , and discarded. To remove residual sterilant, an equal volume of de-ionised or purified water is drawn into the device 1 and ejected, and this step is repeated. An equal amount of a specified culture medium, known to support growth of the bacterial spores, is then drawn into the device 1 , and this is incubated under the specified conditions.
  • a cap or the like may be fitted over the end of the spout 9 after introduction of the culture medium.
  • the medium in the device 1 may be inspected visually for turbidity. If the medium possesses the same transparency as prior to incubation, this is an indication that sterilization has occurred, and hence that the sterilant is effective.
  • Such tests can be performed whilst articles are being sterilized in a bath of sterilant liquid. An aliquot of sterilant is drawn into the device 1 as described and the result of the test is used to verify the efficacy of the sterilant.

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  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Proteomics, Peptides & Aminoacids (AREA)
  • Epidemiology (AREA)
  • Zoology (AREA)
  • General Health & Medical Sciences (AREA)
  • Public Health (AREA)
  • Wood Science & Technology (AREA)
  • Engineering & Computer Science (AREA)
  • Immunology (AREA)
  • Biochemistry (AREA)
  • Biotechnology (AREA)
  • Analytical Chemistry (AREA)
  • Microbiology (AREA)
  • Molecular Biology (AREA)
  • Physics & Mathematics (AREA)
  • Veterinary Medicine (AREA)
  • Animal Behavior & Ethology (AREA)
  • Biophysics (AREA)
  • Bioinformatics & Cheminformatics (AREA)
  • General Engineering & Computer Science (AREA)
  • Genetics & Genomics (AREA)
  • Measuring Or Testing Involving Enzymes Or Micro-Organisms (AREA)
  • Apparatus Associated With Microorganisms And Enzymes (AREA)
  • Electrical Discharge Machining, Electrochemical Machining, And Combined Machining (AREA)
  • Application Of Or Painting With Fluid Materials (AREA)
  • Maintenance And Management Of Digital Transmission (AREA)
  • Investigating Or Analysing Biological Materials (AREA)

Abstract

A test device (1) for assessing the biocidal efficacy of a liquid comprises a vessel (2), means (3) for introducing a predetermined volume of the liquid into the vessel (2) via an inlet (9), and a porous filter (7) interposed between the inlet (9) and the vessel (2). The vessel (2) contains a predetermined quantity of biologically active organisms and the filter (7) has a pore size effective to retain said organisms.
There is also disclosed a method for assessing the biocidal efficacy of a liquid.

Description

  • This invention relates to a test device and method, in particular to a device and method for testing the biocidal efficacy of a liquid sterilant. [0001]
  • The efficacy of sterilization processes is generally assessed by the use of biological indicators; these consist of a known number of micro-organisms, established as having a high resistance to the particular process, attached to or suspended on an inert carrier. For most sterilization processes, the use of bacterial spores inoculated onto a paper disc carrier is sufficient. [0002]
  • When dealing with liquid sterilants, however, there is a danger of release of the bacterial spores into the sterilization fluid medium. A conventional carrier is therefore inappropriate due to a likelihood of contamination of the sterilization fluid. [0003]
  • There has now been devised a test device and method which overcomes or substantially mitigates the problems associated with conventional methods of testing liquid sterilants. [0004]
  • According to the invention, a test device for assessing the biocidal efficacy of a liquid comprises a vessel, means for introducing a predetermined volume of the liquid into the vessel via an inlet, and a porous filter interposed between the inlet and the vessel, wherein the vessel contains a predetermined quantity of biologically active organisms and the filter has a pore size effective to retain said organisms. [0005]
  • According to another aspect of the invention, a method for assessing the biocidal efficacy of a liquid comprises [0006]
  • a) providing a vessel in communication with an inlet and containing a known quantity of biologically active organisms, the inlet being separated from the vessel by a porous filter having a pore size effective to retain said organisms, [0007]
  • b) introducing a predetermined volume of the liquid into the vessel via the inlet, [0008]
  • c) removing the liquid from the vessel via the inlet or via an outlet with a similarly effective filter, [0009]
  • d) introducing a culture medium for the biologically active organisms into the vessel, and [0010]
  • e) ascertaining whether growth of biologically active organisms takes place in the culture medium. [0011]
  • The device and method of the invention are advantageous primarily in that they enable testing of the biocidal activity of a liquid without the risk of contamination of the liquid with organisms utilised in the test procedure. [0012]
  • In a preferred embodiment, the vessel takes the form of a syringe. The syringe plunger is used to draw up the predetermined volume of liquid and subsequently to expel the liquid and to draw up the culture medium. [0013]
  • The filter is preferably housed in a filter unit attached to the syringe. Both the syringe and the filter unit are preferably disposable. The syringe is preferably of the disposable polyethylene or polypropylene type, equipped with a luer lock hub, generally with a capacity not exceeding ten millilitres. The filter unit is preferably of the disposable sealed unit type, in which the housing may consist of polyethylene, polyvinyl chloride, polypropylene, polystyrene or similar polymers. The housing preferably possesses a luer lock inlet. [0014]
  • The filter unit preferably contains a filter membrane, most preferably in disc form. The membrane may consist of cellulose esters, polytetrafluoroethylene, polyvinylidene difluoride, nylon, polycarbonate or any other suitable polymer, or glass fibre material. In addition, the membrane may be pre-treated so as to create hydrophilic and hydrophobic regions. [0015]
  • Polytetrafluoroethylene is a currently preferred membrane material. [0016]
  • Most preferably, the predetermined quantity of biologically active organisms is deposited on the filter, on the side of the filter connected to the syringe. The organisms may be deposited on the membrane by a number of methods, including passing a suspension of organisms through the membrane, or depositing a suspension of organisms, in a volatile solvent, on the membrane and allowing the solvent to evaporate. [0017]
  • The method of the invention may comprise time delays between steps b) and c), and/or between steps d) and e). In addition, one or more washing steps, eg comprising introduction and removal of an appropriate rinsing agent, eg water, may take place between steps c) and d). [0018]
  • The step of ascertaining whether growth of biologically active organisms has taken place in the culture medium may comprise visual inspection, eg for the presence of turbidity. [0019]
  • The method and device of the invention may be utilised in connection with any form of biologically active organism which is conventionally killed using a liquid sterilant. One example is bacterial spores.[0020]
  • The invention will now be described in greater detail, by way of illustration only, with reference to the accompanying drawing which shows a schematic sectional view of a device according to the invention.[0021]
  • Referring to the drawing, a device for testing the efficacy of a sterilant liquid is generally designated [0022] 1 and comprises a disposable clear plastics syringe 2 with a plunger 3. The syringe 2 has a nozzle 4 which is fixed in a corresponding luer lock neck 5 of a filter unit 6.
  • The [0023] filter unit 6 is also disposable and of clear plastics material, and takes the form of a hollow disc. The unit 6 comprises upper and lower (as viewed in the drawing) halves 6 a, 6 b which are joined at their adjoining peripheries and which sandwich a disc 7 of porous membrane material between them. The lower half 6 b has a central open spigot 8 on which a spout 9 is fitted. The upper (as viewed in the drawing) surface of the membrane disc 7 is inoculated with a known quantity of bacterial spores.
  • In use, a defined quantity of test sterilant is drawn into the device [0024] 1 (ie through the inoculated membrane 7 connected by luer lock to the syringe 2) by raising the plunger 3, and is allowed to remain in the device for the required sterilization time. At the end of this period, the sterilant is ejected from the device 1 by depressing the plunger 3, and discarded. To remove residual sterilant, an equal volume of de-ionised or purified water is drawn into the device 1 and ejected, and this step is repeated. An equal amount of a specified culture medium, known to support growth of the bacterial spores, is then drawn into the device 1, and this is incubated under the specified conditions. If necessary or desired, a cap or the like (not shown) may be fitted over the end of the spout 9 after introduction of the culture medium. At the end of this stage, the medium in the device 1 may be inspected visually for turbidity. If the medium possesses the same transparency as prior to incubation, this is an indication that sterilization has occurred, and hence that the sterilant is effective.
  • Such tests can be performed whilst articles are being sterilized in a bath of sterilant liquid. An aliquot of sterilant is drawn into the device [0025] 1 as described and the result of the test is used to verify the efficacy of the sterilant.

Claims (15)

1. A test device for assessing the biocidal efficacy of a liquid, said test device comprising
a vessel,
an inlet in communication with said vessel,
means for introducing a predetermined volume of a liquid into said vessel via said inlet, and
a porous filter interposed between said inlet and said vessel,
wherein said vessel contains a predetermined quantity of biologically active organisms and said filter has a pore size effective to retain said organisms.
2. A device as claimed in
claim 1
, wherein said vessel takes the form of a syringe.
3. A device as claimed in
claim 1
, wherein said vessel takes the form of a syringe and said filter is housed in a filter unit attached to said syringe.
4. A device as claimed in
claim 3
, wherein both said syringe and said filter unit are disposable.
5. A device as claimed in
claim 2
, wherein said syringe is of polyethylene or polypropylene.
6. A device as claimed in
claim 3
, wherein said filter unit has a housing of a material selected from the group consisting of polyethylene, polyvinyl chloride, polypropylene, polystyrene and similar polymers.
7. A device as claimed in
claim 3
, wherein said filter unit contains a filter membrane.
8. A device as claimed in
claim 3
, wherein said filter unit contains a filter membrane in disc form.
9. A device as claimed in
claim 3
, wherein said filter unit contains a filter membrane of a material selected from the group consisting of cellulose esters, polytetrafluoroethylene, polyvinylidene difluoride, nylon, polycarbonate and glass fibre.
10. A device as claimed in
claim 3
, wherein said filter unit contains a filter membrane of polytetrafluoroethylene.
11. A device as claimed in
claim 2
, wherein the predetermined quantity of biologically active organisms is deposited on said filter, on a side of said filter connected to said syringe.
12. A method for assessing the biocidal efficacy of a liquid comprising
a) providing a vessel in communication with an inlet and containing a known quantity of biologically active organisms, the inlet being separated from the vessel by a porous filter having a pore size effective to retain said organisms,
b) introducing a predetermined volume of the liquid into the vessel via the inlet,
c) removing the liquid from the vessel via the inlet or via an outlet with a similarly effective filter,
d) introducing a culture medium for the biologically active organisms into the vessel, and
e) ascertaining whether growth of biologically active organisms takes place in the culture medium.
13. A method as claimed in
claim 12
, further comprising time delays between steps b) and c), and/or between steps d) and e).
14. A method as claimed in
claim 12
, further comprising one or more washing steps between steps c) and d).
15. A method as claimed in
claim 12
, wherein the step of ascertaining whether growth of biologically active organisms has taken place in the culture medium comprises visual inspection.
US09/052,303 1997-04-04 1998-03-31 Device and method for testing biocidal efficacy of a liquid Expired - Fee Related US6406879B2 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
GB9706902 1997-04-04
GBGB9706902.5 1997-04-04
GBGB9706902.5A GB9706902D0 (en) 1997-04-04 1997-04-04 Test device and method

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US20010039030A1 true US20010039030A1 (en) 2001-11-08
US6406879B2 US6406879B2 (en) 2002-06-18

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EP (1) EP0977884B1 (en)
AT (1) ATE273398T1 (en)
AU (1) AU6741298A (en)
DE (1) DE69825582T2 (en)
DK (1) DK0977884T3 (en)
ES (1) ES2226114T3 (en)
GB (1) GB9706902D0 (en)
PL (1) PL188971B1 (en)
WO (1) WO1998045470A1 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2003046505A2 (en) * 2001-11-30 2003-06-05 Sy-Lab Vgmbh Device for detecting carbon dioxide and method for determining a microbiological contamination of a fluid
US20130040333A1 (en) * 2010-06-10 2013-02-14 Hemcheck Sweden Aktiebolag Arrangement for detection of hemolysis

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE29903174U1 (en) * 1999-02-22 1999-05-06 BHT Hygiene-Technik Ing. H. Biermaier GmbH, 86316 Friedberg Device for checking the cleaning result of dishwashers, in particular disinfection dishwashers for medical devices
GB0002382D0 (en) * 2000-02-03 2000-03-22 Browne Albert Ltd Sterilizer test device
US10426943B2 (en) 2011-08-11 2019-10-01 Attwill Medical Solutions Sterilflow L.P. Insert for luer connection
EP3145560A4 (en) 2014-05-21 2018-01-17 Attwill Medical Solutions Steriflow L.P. Insert for catheter system
ES2671844B1 (en) 2015-06-11 2019-03-22 Attwill Medical Solutions Inc Medical devices, systems and methods that use anti-thrombin heparin compositions.
JP7447125B2 (en) 2018-12-28 2024-03-11 エイエスピー・グローバル・マニュファクチャリング・ゲーエムベーハー Articles, systems and methods for displaying processes

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3999945A (en) * 1974-08-30 1976-12-28 Delta Scientific Corporation Liquid analysis system
DE3705596A1 (en) * 1986-11-24 1988-09-01 Volker Barkey Apparatus for detecting a disinfection process
FR2687476B1 (en) * 1992-02-13 1994-05-20 Millipore Sa DEVICE FOR VERIFYING THE STERILITY OF A FLUID.
US5407269A (en) * 1992-07-09 1995-04-18 International Business Machine Corporation Dynamic mixing chamber
US5443985A (en) * 1993-07-22 1995-08-22 Alberta Research Council Cell culture bioreactor
US5516648A (en) * 1994-08-18 1996-05-14 Steris Corporation Encapsulated biological indicator
EP0863994B1 (en) * 1995-07-28 2002-02-20 Minnesota Mining And Manufacturing Company Multi-zone sterility indicator

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2003046505A2 (en) * 2001-11-30 2003-06-05 Sy-Lab Vgmbh Device for detecting carbon dioxide and method for determining a microbiological contamination of a fluid
WO2003046505A3 (en) * 2001-11-30 2003-09-12 Sy Lab Vgmbh Device for detecting carbon dioxide and method for determining a microbiological contamination of a fluid
US20130040333A1 (en) * 2010-06-10 2013-02-14 Hemcheck Sweden Aktiebolag Arrangement for detection of hemolysis
US8846333B2 (en) * 2010-06-10 2014-09-30 Hemcheck Sweden Ab Method and device for visual detection of hemolysis

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Publication number Publication date
DE69825582D1 (en) 2004-09-16
PL335877A1 (en) 2000-05-22
ATE273398T1 (en) 2004-08-15
EP0977884A1 (en) 2000-02-09
PL188971B1 (en) 2005-05-31
GB9706902D0 (en) 1997-05-21
ES2226114T3 (en) 2005-03-16
WO1998045470A1 (en) 1998-10-15
EP0977884B1 (en) 2004-08-11
DK0977884T3 (en) 2004-11-29
AU6741298A (en) 1998-10-30
US6406879B2 (en) 2002-06-18
DE69825582T2 (en) 2005-09-15

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Owner name: ALBERT BROWNE LIMITED, UNITED KINGDOM

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