FR2910328A1 - Sterilization indicator for indicating presence of oxygen and nitrogen atoms in after-discharge plasma, has supports selected from compounds rendered more hydrophilic during contacting with oxygen and nitrogen atoms present in plasma - Google Patents

Sterilization indicator for indicating presence of oxygen and nitrogen atoms in after-discharge plasma, has supports selected from compounds rendered more hydrophilic during contacting with oxygen and nitrogen atoms present in plasma Download PDF

Info

Publication number
FR2910328A1
FR2910328A1 FR0611341A FR0611341A FR2910328A1 FR 2910328 A1 FR2910328 A1 FR 2910328A1 FR 0611341 A FR0611341 A FR 0611341A FR 0611341 A FR0611341 A FR 0611341A FR 2910328 A1 FR2910328 A1 FR 2910328A1
Authority
FR
France
Prior art keywords
dye
support
oxygen
indicator
plasma
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
FR0611341A
Other languages
French (fr)
Inventor
Andre Ricard
Francis Dieras
Michel Sixou
Sandrine Villeger
Cristina Canal
Pilar Erra
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
SATELEC SOC
Original Assignee
SATELEC SOC
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by SATELEC SOC filed Critical SATELEC SOC
Priority to FR0611341A priority Critical patent/FR2910328A1/en
Publication of FR2910328A1 publication Critical patent/FR2910328A1/en
Application status is Withdrawn legal-status Critical

Links

Classifications

    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61LMETHODS 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
    • A61L2/00Methods or apparatus for disinfecting or sterilising materials or objects other than foodstuffs or contact lenses; Accessories therefor
    • A61L2/26Accessories or devices or components used for biocidal treatment
    • A61L2/28Devices for testing the effectiveness or completeness of sterilisation, e.g. indicators which change colour

Abstract

The subject of the invention is a sterilization indicator (17), in particular in the form of a kit, characterized in that it comprises: a dye (24) and a support (21,22) intended to be put into contact with the dye (24), and selected from the compounds rendered more hydrophilic, at least in part, when they come into contact with oxygen O and / or nitrogen N atoms.

Description

The present invention relates to a sterilization indicator, usable

  in particular for the sterilization of medical or surgical instruments, in particular for dental use, using a plasma obtained from a gas based on nitrogen and / or oxygen. Sterilization consists in destroying, in a given proportion, a significant number of microorganisms, viruses or pathogenic proteins present on the surface, internal or external, of the objects to be treated.

  It should be noted that the sterile adjective is an absolute term, but the assurance that an object is sterile, that is, free of microorganisms, is a probability function. The level of sterility assurance level (SAL) of a product is defined as the probability that any given unit is unsterile after exposure to a validated sterilization process. Thus, for a product to be considered sterile under the European standard EN556, it must have a sterility assurance level of 10-6, that is, the theoretical probability of isolating a microorganism must be less than 1 for 106. Various sterilization processes are known, including chemical and physical processes.

  Among the chemical sterilization processes, mention may be made of processes using gases such as ethylene oxide, formaldehyde or hydrogen peroxide. These methods, however, have the disadvantage of requiring a significant period of desorption incompatible with rapid availability of the 2910328 - 2 instruments to be treated. In addition, these gases are toxic and irritate skin and mucous membranes. The physical processes include vapor phase sterilization in an autoclave under the action of temperature and steam; hot sterilization by the dry route; ion beam or gamma ray radiation, used on objects that can not be sterilized by heat or chemically; or filtration, using filters capable of separating microorganisms. These processes generally involve high temperatures, often greater than 100 C. Due to the increasing use of heat-sensitive materials, such as polymer-based materials, in medical objects, it has been found desirable to develop sterilization methods for low temperature, and especially at temperatures below 70 C. Thus, processes for sterilization using a plasma, and in particular a post-discharge plasma, operating at temperatures that make it possible not to deteriorate the thermosensitive materials. For example, application WO 00/72889 discloses a sterilization process employing a plasma based on oxygen and nitrogen. The application FR 2 856 600 describes a process for sterilization using a post-discharge plasma emanating from a plasma consisting exclusively of nitrogen, whereas the application FR 2 879 933 uses a plasma of post discharge from a plasma consisting of hydrogen and nitrogen. Many sterilization processes thus use a nitrogen-based or oxygen-based gas for the creation of the plasma. For sterilizer validation, sterilization indicators are used which control one or more essential parameters of the sterilization process. To this end, three types of sterilization indicators have been developed: physical, chemical and biological indicators. Sterilization indicators for plasma plating processes are still poorly developed. US 6,659,036, WO 98/46279, JP 2005111154 and JP 2004298479 are known sterilization indicators relating to processes using plasmas. However, these documents do not relate to nitrogen and / or oxygen-based plasmas. It thus appears necessary to have sterilization indicators, which make it possible to evaluate at least one parameter of the sterilization process, for sterilization processes using a post-discharge plasma obtained from a gas comprising nitrogen N2 and / or oxygen O2. The Applicant has developed a sterilization indicator to achieve this goal. In particular, the indicator according to the invention makes it possible to indicate the presence of oxygen O and / or nitrogen N atoms in a post-discharge plasma. The sterilization indicator according to the invention, which can be used in a sterilization device, can be in particular in the form of a kit. The indicator 30 comprises: a dye, in particular a hydrophilic dye, and a support, intended to be brought into contact with the dye, and chosen from compounds made more hydrophilic, at least in part, when they are put into contact with the dye; The dye and the carrier can be used together or separately as a kit. It is thus possible to envisage placing the support alone in the sterilization chamber, and to apply the dye to the support at the end of the process. The dye may also be contacted with the carrier prior to introduction of the indicator into the sterilization chamber. In a preferred embodiment, the dye is disposed within the carrier. It may in particular be arranged in a capsule, inside the support. It is possible to use any type of dye-impermeable capsule, for example a plastic envelope, glass, a polymeric compound, a breakable ampoule or a capsule used in cosmetics. A material which can be broken under the action of a manual type of pressure is preferably used to facilitate contacting the dye with the support. The dye may be chosen from all the usual dyes, in particular inks, pigments and paints. The dye is preferably in the liquid state, in solution or in suspension, but may also be in pasty form. The support is chosen from the compounds made more hydrophilic, at least in part, when they come into contact with oxygen O and / or nitrogen N atoms present in the post-discharge plasma.

Those skilled in the art will be able to choose this support by comparing the diffusion of the dye in the support with and without sterilization. If the diffusion of the dye in a support subjected to the sterilization process is greater than the diffusion of the same amount of dye in an untreated support, it is because the support has been made more hydrophilic, and therefore it is necessary to for the indicator according to the invention. Those skilled in the art may also use the contact angle measurement employed in known surface energy measurement techniques. When a drop of liquid is deposited on a flat solid surface, the angle between the tangent to the drop at the point of contact and the solid surface is called the contact angle. It thus accounts for the ability of a liquid to spread over a surface and depends on the interactions between the liquid and the solid. It is the degree of spreading of the dye that makes it possible to evaluate the hydrophilic nature of the support. The support is preferably chosen from porous supports in order to facilitate diffusion of the dye into the support. The support may for example be chosen from cellulose, fabrics, cotton, polymers, paper, blotting paper.

Although the support may be a hydrophilic carrier, it is preferably selected from the hydrophobic carriers. It may also be chosen from hydrophilic supports subjected to a preliminary treatment, for example of finishing, rendering them hydrophobic. For example, a treatment with a fluorocarbon agent or a hydrophobic polysiloxane softener may be used. The invention also relates to a method for indicating the presence of oxygen O and / or N nitrogen atoms in a post-discharge plasma. The process is advantageously carried out in a post-discharge zone of a sterilization device using a plasma obtained from a gas comprising oxygen O 2 and / or nitrogen N 2. The process comprises successively: contacting with the plasma a support chosen from compounds rendered more hydrophilic, at least in part, when they come into contact with oxygen and / or nitrogen atoms N, - contacting the support with a given amount of a hydrophilic dye, causing diffusion of the dye in the support and thus the formation of a diffusion zone, - comparison of this diffusion zone with a zone sample broadcast.

The control diffusion zone may be a predetermined diffusion zone, fixed for example according to the parameters employed during the sterilization process. The control diffusion zone may also be the diffusion zone of the same amount of hydrophilic dye in the support not in contact with the plasma. Thus, by comparing the diffusion of the dye in the support subjected to the process of the invention with that of the control diffusion zone, it will be possible to ascertain whether the support of the invention subjected to the sterilization has been made more hydrophilic. The increase in the area of the diffusion zone of the dye in the support is in fact proportional to the increase in the hydrophilicity of the support. Pairing or increasing the area of the dye diffusion zone is an indicator of hydrophilicity.

An indicator comprising a hydrophilic dye disposed in a capsule is preferably used within the support. According to a first embodiment, the step of bringing the support into contact with the dye is carried out by applying a pressure on the capsule, so as to break the capsule. According to another embodiment, the capsule is chosen so that the presence of nitrogen N and / or O oxygen atoms renders the capsule porous or permeable during sterilization, which allows contacting and the diffusion of the dye into the support without it being necessary to apply pressure on the capsule at the end of the process. Such a capsule may be chosen from glass capsules, plastic capsules, gelatinous capsules.

Other objects, features and advantages of the invention will emerge on reading the following description, given purely by way of example, and with reference to the appended drawings, in which: FIG. 1 schematically illustrates a 30 a sterilization device with an indicator according to the invention, 2 and 3 show a sectional view of the indicator in two successive steps of an embodiment of the method according to the invention, the Figure 4 shows the indicator in plan view at the end of the process. The sterilization device, as illustrated in FIG. 1, comprises an inlet pipe 1 of a stream of nitrogen N 2 which passes through a chamber 2 under vacuum subjected to an electric field produced by a generator 10 of 10 micrometers. 2.45 GHz waves. The electric field notably causes the formation of N atoms from the N2 molecules. The plasma thus produced is conveyed to a sterilization chamber 4 via a line 5, using a vacuum pump 6. The chamber 4 is supplied with plasma via a nozzle 15. The nozzle 15 may advantageously be terminated by one or more injectors for homogenizing the plasma flow. The vacuum pump 6 also discharges the plasma outwards through a pipe 7 provided with filters 8.

The sterilization chamber 4 is called the post-discharge chamber because: The plasma is not subjected to an electric field, while it was in the chamber 2. The plasma present in the chamber 4 Thus, said post-discharge plasma, which is not subjected to an electric field, thus no longer contains UV radiation, nor ions and electrons, which makes it possible to avoid excessive heating in chamber 4. The sterilization chamber 4, parallelepipedal shape, comprises a metal instrument holder 9 which is intended to receive the objects 10 to be sterilized. The instrument holder 9 is provided with heating means 11 whose temperature is controlled by a control device 12. These heating means may in particular be an electrical resistance or induction heating means.

The sterilization chamber 4 is closed on one of its sides by a pivoting door 13. The chamber 4 can also be provided with a reflector 14 and a fan 16 which contribute to the homogenization of the plasma.

The objects 10 to be sterilized and one or more sterilization indicators 17 are introduced into the chamber 4. The sterilization indicators 17 can be arranged in the whole of the chamber 4, and particularly in the hard-to-reach places, as against 15 the walls or under the objects 10 to be sterilized. In this way, it will be possible to ensure that the entire volume of the treatment chamber is treated with the nitrogen plasma. It is also particularly useful to have the sterilization indicators 17 on the sterilization pouches containing the objects to be treated, or within them, to ensure that the objects themselves have been in contact. The pressure in the sterilization chamber 4 is preferably less than 105 Pa, in order to facilitate contacting the nitrogen atoms N with the objects 10. Figure 2 a sterilization indicator 17 according to an embodiment of the invention. The sterilization indicator 17 comprises a glass capsule 23 containing ink 24. The capsule 23 is inserted between two sheets 21 and 22 of blotting paper, interconnected at their ends 25 and 26.

At the end of the sterilization process, the indicator 17 is removed from the chamber 4. A pressure P is applied to the indicator 17, for example by a slight manual pressure, as shown in FIG. to break the capsule 23 and to release the ink 24 which will thus come into contact with the sheets 21 and 22 of blotting paper support, and diffuse within the support 21,22. The support 21,22, due to its contact with the nitrogen atoms N present in the plasma, during the sterilization process, is rendered more hydrophilic, at least over a portion of the thickness of the layers 21, 22, which will allow the diffusion of the ink 24 in the support 21,22, as illustrated in FIG. 4. A scattering zone is thus observed which substantially forms a disc of radius R. This is then compared with disc of radius R with a control diffusion zone of radius R ', which makes it possible to affirm whether or not the indicator has been in contact with the nitrogen atoms N during sterilization.

If the radius R is less than the radius R ', or even zero, it means that the diffusion of the dye has been insufficient, and that the support 21,22 has therefore not been made sufficiently hydrophilic, and therefore has not has been in contact with a sufficient amount of N-atoms of the post-discharge plasma, which implies insufficient sterilization. If instead the radius R 2910328 - 11 - is substantially equal to the radius R ', the test is successful, and it can be concluded that the indicator has been brought into contact with the desired dose of nitrogen atoms N. The determination the radius R 'of the control diffusion zone 5 is carried out taking into account the various parameters that it is desired to use during the sterilization process, such as the concentration of nitrogen in the plasma, the duration of the exposure of the objects 10 the plasma temperature, the temperature in the sterilization chamber 4, and the volume of objects 10. The nitrogen concentration may be selected by adjusting the power of the microwave generator 3 and the nitrogen flow. The determination of the radius R 'also takes into account the nature of the support 21,22, since the change in the surface energy of the support 21,22 due to the contact with the nitrogen atoms, and which leads to hydrophilic increase, depends on the support 21,22. In a variant, a thermochromic dye may be used instead of the ink 24, the color change temperature of which will be chosen as a function of the temperature which it is desired to fix in the sterilization chamber 4. This variant makes it possible to advantageously to check the temperature, in addition to the nitrogen atom content. Two parameters of the sterilization process are thus validated. It may be decided to determine the level of assurance of sterility as a function of nitrogen pressure and flow rate, nitrogen nitrogen content, temperature in the sterilization chamber, and sterilization time. Since the nitrogen atom density N is proportional to the power of the microwave generator 3, to the pressure and to the nitrogen flow rate, the parameters to be verified will be the temperature, the carbon atom content, nitrogen and the duration of treatment. Thanks to the thermochromic indicator, which makes it possible to check the temperature in the sterilization chamber 54 and the nitrogen atom content N, it is only necessary to measure the sterilization time to check the three parameters. The parameters of the sterilization may be as follows: temperature: 60 C; pressure: 6.66102 Pa; Nitrogen flow rate: 1 L / min; post-discharge plasma exposure time: 40 min. The sterilization indicator 17 according to the invention is therefore particularly suitable for ensuring that the nitrogen atoms N present in the post-discharge plasma 15 have been in contact with the whole of the sterilization chamber, as well as with the objects 10 to be sterilized. Indicator 17 also functions with post-discharge plasmas obtained from gases comprising a mixture of nitrogen N 2 with other species, such as plasmas obtained from N 2 / H 2, or Ar / N 2. The indicator 17 also functions with the oxygen O atoms present in a post-discharge plasma obtained from a gas comprising oxygen O 2, such as plasmas obtained from N 2 / O 2 or Ar / O 2. 25

Claims (9)

  1.   Sterilization indicator (17), in particular in the form of a kit, characterized in that it comprises: a dye (24), and a support (21,22) intended to be brought into contact with the dye ( 24), and selected from the compounds made more hydrophilic, at least in part, when they come into contact with O oxygen atoms and / or nitrogen N.
  2.   2. Indicator (17) according to claim 1, characterized in that the dye (24) is disposed in a capsule (23), inside the support (21,22).
  3.   3. Indicator (17) according to one of claims 1 or 2, characterized in that the carrier (21,22) is porous.
  4.   4. Indicator (17) according to claim 3, characterized in that the support (21,22) is selected from cellulose, fabrics, cotton, polymers, paper, blotting paper. 20
  5.   5. Indicator (17) according to one of claims 1 to 4, characterized in that the dye (24) is selected from inks, pigments, paints.
  6.   6. Indicator (17) according to claim 5, characterized in that the dye (24) is a thermochromic dye.
  7.   7. Use of an indicator (17) according to one of claims 1 to 6 in a sterilization device. 2910328 - 14 -
  8.   8. Use according to claim 7, for the indication of the presence of O oxygen atoms and / or N nitrogen in a post-discharge plasma.
  9.   9. A method for indicating the presence of oxygen O and / or nitrogen N atoms in a post-discharge plasma, characterized in that it comprises successively: the contact with the plasma of a support (21,22) selected from the compounds made more hydrophilic, at least partially, when they come into contact with oxygen O and / or N nitrogen atoms, - the contacting of the support with a given amount of a hydrophilic dye (24), causing diffusion of the dye (24) into the support (21,22) and thus the formation of a diffusion zone; -comparison of this diffusion zone with a control diffusion zone. 13. The method according to claim 9, characterized in that the control diffusion zone is the diffusion zone of the same given quantity of hydrophilic dye (24) in a support (21,22) not brought into contact. with the gaseous plasma. Process according to claim 9 or 10, characterized in that a sterilization indicator (17) according to claim 2 is used, the step of contacting the carrier (21,22) with the dye (24). being performed by applying pressure on the capsule (23), so as to break the capsule (23).
FR0611341A 2006-12-22 2006-12-22 Sterilization indicator for indicating presence of oxygen and nitrogen atoms in after-discharge plasma, has supports selected from compounds rendered more hydrophilic during contacting with oxygen and nitrogen atoms present in plasma Withdrawn FR2910328A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
FR0611341A FR2910328A1 (en) 2006-12-22 2006-12-22 Sterilization indicator for indicating presence of oxygen and nitrogen atoms in after-discharge plasma, has supports selected from compounds rendered more hydrophilic during contacting with oxygen and nitrogen atoms present in plasma

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
FR0611341A FR2910328A1 (en) 2006-12-22 2006-12-22 Sterilization indicator for indicating presence of oxygen and nitrogen atoms in after-discharge plasma, has supports selected from compounds rendered more hydrophilic during contacting with oxygen and nitrogen atoms present in plasma

Publications (1)

Publication Number Publication Date
FR2910328A1 true FR2910328A1 (en) 2008-06-27

Family

ID=38293324

Family Applications (1)

Application Number Title Priority Date Filing Date
FR0611341A Withdrawn FR2910328A1 (en) 2006-12-22 2006-12-22 Sterilization indicator for indicating presence of oxygen and nitrogen atoms in after-discharge plasma, has supports selected from compounds rendered more hydrophilic during contacting with oxygen and nitrogen atoms present in plasma

Country Status (1)

Country Link
FR (1) FR2910328A1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR3074048A1 (en) * 2017-10-23 2019-05-31 Societe Pour La Conception Des Applications Des Techniques Electroniques Device for sterilizing an object with flow deflector

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3738811A (en) * 1971-07-01 1973-06-12 Kendall & Co Residual alkylating agent detector and method therefor
EP0069037A1 (en) * 1981-06-26 1983-01-05 Guy Charvin Sterilization indicator
EP0628317A1 (en) * 1993-06-09 1994-12-14 PyMaH Corporation Simplified sterilizer vacuum test pack
WO1995024933A1 (en) * 1994-03-15 1995-09-21 Abtox, Inc. Packaging systems for peracid sterilization processes
EP1052507A2 (en) * 1999-05-14 2000-11-15 Ethicon Inc. Chemical indicator
US20010054374A1 (en) * 1999-12-15 2001-12-27 Takeshi Omatsu Plasma sterilization indicator
EP1201255A2 (en) * 2000-10-27 2002-05-02 Ethicon Inc. Biological indicator for sterilization processes with double buffer system

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3738811A (en) * 1971-07-01 1973-06-12 Kendall & Co Residual alkylating agent detector and method therefor
EP0069037A1 (en) * 1981-06-26 1983-01-05 Guy Charvin Sterilization indicator
EP0628317A1 (en) * 1993-06-09 1994-12-14 PyMaH Corporation Simplified sterilizer vacuum test pack
WO1995024933A1 (en) * 1994-03-15 1995-09-21 Abtox, Inc. Packaging systems for peracid sterilization processes
EP1052507A2 (en) * 1999-05-14 2000-11-15 Ethicon Inc. Chemical indicator
US20010054374A1 (en) * 1999-12-15 2001-12-27 Takeshi Omatsu Plasma sterilization indicator
EP1201255A2 (en) * 2000-10-27 2002-05-02 Ethicon Inc. Biological indicator for sterilization processes with double buffer system

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR3074048A1 (en) * 2017-10-23 2019-05-31 Societe Pour La Conception Des Applications Des Techniques Electroniques Device for sterilizing an object with flow deflector

Similar Documents

Publication Publication Date Title
US9192164B2 (en) Membrane sterilization
JP5785208B2 (en) sterilization method and apparatus
US9561478B2 (en) Separation membrane, method of producing the same and separation membrane module using the separation membrane
Jacobs et al. Plasma surface modification of polylactic acid to promote interaction with fibroblasts
Ikawa et al. Effects of pH on bacterial inactivation in aqueous solutions due to low‐temperature atmospheric pressure plasma application
EP0019211B1 (en) Process for purifying aqueous liquids
AU750510B2 (en) Monitoring of cleaning process
EP0923951B1 (en) Container for cleaning or sterilizing lumen devices
US6193931B1 (en) Container monitoring system
EP0278623B1 (en) Hydrogen peroxide plasma sterilization system
DE60006142T2 (en) METHOD AND APPARATUS FOR STEAM PHASE Sterilization
JP4689090B2 (en) Method for determining load suitability for sterilization
EP1647284B1 (en) Sensor-controlled method and apparatus for sterilizing
US6656427B2 (en) Sterilization process without sterile rinse
EP1819368B1 (en) Hydrogen peroxide vapor sterilizer and sterilizing methods using the same
AU762074B2 (en) Method of enhanced sterilization with improved material compatibility
EP0465569B1 (en) Process and apparatus for dry sterilization of medical devices and materials
Deilmann et al. Low-pressure microwave plasma sterilization of polyethylene terephthalate bottles
EP1165151B1 (en) Indicators for monitoring sterilization with plasma
CN100419412C (en) Sensor for determining concentration of fluid sterilant
AU758584B2 (en) Sterilization process using small amount of sterilant to determime the load
Chen et al. Surface modification of poly (ether sulfone) ultrafiltration membranes by low‐temperature plasma‐induced graft polymerization
Zhang et al. Assessment of the roles of various inactivation agents in an argon-based direct current atmospheric pressure cold plasma jet
Wekhof et al. Pulsed UV disintegration (PUVD): a new sterilisation mechanism for packaging and broad medical-hospital applications
US5518927A (en) Instrument sterilation life-span indicator

Legal Events

Date Code Title Description
ST Notification of lapse

Effective date: 20100831