Abstract:
A method for cleaning and sterilizing a medical device comprises the steps of placing the device into a container, contacting the device with a cleaning solution, contacting the device with a liquid sterilant and lowering pressure in the container to vaporize the liquid sterilant in the container, thereby simultaneously completing sterilization of the device and drying the device. The washing and sterilization processes can proceed simultaneously.

Description:
[0001]     This application is a continuation-in-part of U.S. application Ser. No. 10/632039 filed Jul. 31, 2003 which is a continuation-in-part of U.S. application Ser. No. 09/746,106 filed Dec. 22, 2000, now U.S. Pat. No. 6,656,427 which is a continuation-in-part of U.S. Pat. No. 08/992,478 filed Dec. 17, 1997, now U.S. Pat. No. 6,203,756 issued on Mar. 20, 2001, each of which is incorporated herein by reference; this application is also a continuation-in-part of U.S. application Ser. No. 10/326,041 filed Dec. 20, 2002 which is continuation of U.S. application Ser. No. 10/132,811 filed Apr. 25, 2002, which is a continuation of U.S. application Ser. No. 09/075,714 filed May 11, 1998, now U.S. Pat. No. 6,394,111 which claims the benefits of Provisional Application No. 60/049,351, entitled “DETECTION OF CLEANLINESS OF A MEDICAL DEVICE DURING A WASHING PROCESS”, filed on Jun. 11, 1997. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     This invention relates to systems and processes for chemical sterilizing or disinfecting medical devices.  
         [0003]     Medical instruments have traditionally been sterilized or disinfected using either heat such as is provided by steam, or a chemical in liquid, gas, or vapor state. Prior to sterilization or disinfection, the instruments to be treated are usually first cleaned and then sterilized or disinfected. Several devices and methods have been developed for washing and sterilizing a device in a single process within a single container and without having to transfer the device from a washing apparatus to a sterilizing apparatus. Heretofore these applications have been limited to processes employing liquid based sterilants.  
         [0004]     U.S. Pat. No. 5,443,801 discloses a transportable cleaning/sterilizing apparatus and method for inside-outside washing and sterilization of medical/dental instruments. The apparatus functions in four sequential cycles: wash, rinse, sterilize, and dry. The sterilization step is conducted using ozonated and purified water, and the drying step is accomplished by injecting ozonated/deozonated sterile warm dry oxygen, or sterile inert gas into and exhausted from the wash chamber under a positive pressure relative to atmospheric. In this process, the device has to be rinsed with purified water after it is sterilized to remove sterilant residue before drying step.  
         [0005]     U.S. Pat. No. 5,505,218 to Steinhauser et al. discloses a device for cleaning, disinfecting and maintaining medical or dental instruments. The device has a pot-shaped container with a multiplicity of mountings in the interior of the container each for one of tool holder, a water supply system, a compressed air supply system, and an ultrasonic transducer. The disinfection is conducted with heated water, and the drying is conducted with hot compressed air. This system is not designed for sterilization.  
         [0006]     U.S. Pat. No. 5,279,799 to Moser et al. discloses apparatus for cleaning and testing endoscopes by injecting pressurized air into the sheath and pressurized air and washing liquid into the ducts. A washing chamber is provided which contains retractable cages to hold the endoscopes during cleaning and testing. This process includes washing, disinfecting, final rinsing with purified water, and air drying the ducts of a tubular article. A number of filters are involved in this system, and this system is not designed for sterilization.  
         [0007]     One disadvantage of the cleaning/sterilizing or cleaning/disinfecting systems of the prior art as discussed above is that, after the device is sterilized or disinfected and before it is dried, the device has to be rinsed with purified water to remove disinfectant or sterilant residues. A so-called bacteria filter is usually used to filter the water to remove particulates and bacteria. Typically, a two-stage filtering system is utilized, for example, a first stage has a 2-5 micron filter and a second stage has a 0.1-0.2 micron filter. However, virus can be smaller than 0.1 micron. This means the virus can penetrate the filtering system recontaminating the sterilized device in the final rinsing process. Another problem associated with the use of a bacteria filter is that bacteria can form biofilms in the filter which are difficult to sterilize and, thus, become a new potential source of contamination.  
         [0008]     In U.S. Pat. No. 6,103,189 to Kralovic attempts to solve the problem of getting sterile water by using a dilute solution of the sterilant to rinse the devices. This has the potential to leave residual sterilant on the devices.  
       SUMMARY OF THE INVENTION  
       [0009]     A method, according to the present invention, for cleaning and sterilizing a medical device comprising the steps of: placing the device into a container, contacting the device with a cleaning solution, contacting the device with a liquid sterilant, and lowering pressure in the container to vaporize the liquid sterilant in the container, thereby simultaneously completing sterilization of the device and drying the device.  
         [0010]     In one aspect of the invention, both the cleaning solution and the liquid sterilant contact the device simultaneously. The liquid sterilant can comprise hydrogen peroxide, chlorine dioxide or dissolved ozone. The device can be stored in the container in sterile form after the sterilization is complete.  
         [0011]     In one aspect of the invention, a rinse solution comprising the liquid sterilant is applied to the device after the step of contacting the device with the cleaning solution.  
         [0012]     In one aspect of the invention, liquid sterilant is drained from the container and a predetermined amount of the liquid sterilant is retained, the predetermined amount of liquid sterilant being vaporized during the step of vaporizing the liquid sterilant in the container. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0013]      FIG. 1   a  is a schematic diagram of a container used in a cleaning/sterilizing process of the present invention.  
         [0014]      FIG. 1   b  is a schematic diagram of a stirrer with fluid inlets used in the container of  FIG. 1 .  
         [0015]      FIG. 1   c  is a schematic diagram of a gas-permeable but microorganism-impermeable barrier installed in a vacuum port of the container of  FIG. 1 .  
         [0016]      FIG. 1   d  is a schematic diagram of a container placed in a vacuum chamber used in a cleaning/sterilizing process of the present invention.  
         [0017]      FIG. 1   e  is a schematic diagram of a container with fluid jet tubes.  
         [0018]      FIG. 2  is a schematic diagram of a container with an adapter used in the cleaning/sterilizing process of the present invention.  
         [0019]      FIG. 3   a  is a schematic diagram of a container with an interface used in the cleaning/sterilizing process of the present invention.  
         [0020]      FIG. 3   b  is a schematic diagram of a shutter used in the interface of the container of  FIG. 3   a.    
         [0021]      FIG. 3   c  is a schematic diagram of a iris valve used in the interface of the container of  FIG. 3   a.    
         [0022]      FIGS. 3   d,    3   e,  and  3   f  are schematic diagrams of two plates forming an opening in the interface of the container of  FIG. 3   a.    
         [0023]      FIG. 3   g  is schematic diagram of an interface of the container of  FIG. 3   a.    
         [0024]      FIG. 4  is a schematic diagram of a container placed in a vacuum chamber used in the process of the present invention.  
         [0025]      FIG. 5   a  is a schematic diagram of a container having two holders in an interface.  
         [0026]      FIGS. 5   b  and  5   c  are schematic diagrams of two holders of the container shown in  FIG. 5   a  holding a lumen device.  
         [0027]      FIG. 5   d  is a schematic diagram of an interface of a container with multiple openings.  
         [0028]      FIG. 6  is a schematic diagram of a container separated into three enclosures by two interfaces according to the present invention.  
         [0029]      FIG. 7   a  is a schematic diagram of a container having an interface and a tray across the interface according to the present invention.  
         [0030]      FIGS. 7   b  and  7   c  are cross-sectional views of the container of  FIG. 7   a  at the location of the interface.  
         [0031]      FIG. 8   a  is a top view of the container of  FIG. 7   a.    
         [0032]      FIG. 8   b  is a top view of a portion of the interface of  FIG. 7   a.    
         [0033]      FIG. 8   c  is a top view of the tray of  FIG. 7   a.    
         [0034]      FIG. 8   d  is a top view of the container of  FIG. 7   a  without the tray and the interface.  
         [0035]      FIG. 9  is a schematic diagram showing a recycle system for processing liquid. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0036]     The cleaning/sterilizing or cleaning/disinfecting process of the present invention can be carried out with various apparatus and incorporated with various sterilization methods, which are described below. In its simplest form a cleaning solution is put into contact with a device, preferably with some agitation or other motion to wash foreign matter from the device. The cleaning solution is preferably rinsed off of the device which is then sterilized, such as by contact with a sterilizing fluid. If desired, cleaning and sterilization can be conducted simultaneously. In one aspect this can be accomplished by using a combined cleaning and sterilizing solution, such as one with dissolved ozone or chlorine dioxide. A hydrogen peroxide solution may also be employed.  
       Method to Deliver a Predetermined Amount of Liquid Sterilant  
       [0037]     This method can be incorporated into the cleaning/sterilizing or cleaning/disinfecting process of the present invention. In order to maximize the efficiency of a vapor sterilization process, it is important and desirable to drain excess sterilant solution and only keep a desired amount of the sterilant solution to vaporize after treating a device to be sterilized with the sterilant solution.  
         [0038]     According to the present invention, a sterilization container or enclosure may have a surface with wells thereon which define a known volume. The well is positioned so that when a liquid sterilant is introduced onto the surface, a known volume of the liquid sterilant fills the well and when the liquid sterilant is drained from the surface, the known volume of liquid sterilant remains in the well so that a subsequent vapor sterilization process can be performed on the device with the known volume of liquid sterilant positioned within the surface. The surface preferably has at least one perforation for draining the liquid sterilant from the surface. The well formed in the surface can be curved, flat or angled. Thus, the well can be an inwardly extending hemispherical projection. The well can also be formed in the surface as an inwardly extending rectangular projection having rounded ends. The well formed in the surface can also be a rectangular box having side walls, defining an opening. Where perforations are provided, they can be disposed adjacent the well, and can be roughly spherical in shape. The upwardly extending projection can include a perforation thereon, which can be on top of the projection or on a side of the projection. The surface can be a sloped surface, a convex or concave surface or a V-shaped surface. The surface can be made of a variety of materials including stainless steels, aluminum, aluminum alloys, liquid crystal polymers, polyesters, polyolefins polymers or fluorinated polyolefins. If the surface is comprised of a composite material, the composite material can include a filler of high thermal conductivity. Examples of composite materials include a metal-filled polymer, a ceramic-filled polymer and a glass-filled polymer. Those materials are also suitable for the side walls and doors of the sterilization container.  
         [0039]     A tray with wells with configurations similar to that described above can be provided with a container or enclosure. The tray can be secured to the container or removably placed in the container.  
       Method Based on Diffusion Restricted Environments  
       [0040]     A method of vapor sterilization or disinfection under diffusion-restricted environments can also be used in corporation with the cleaning/sterilizing or cleaning/disinfecting process of the present invention. In this method, the devices (lumen or non-lumen) to be sterilized are pretreated with a sterilant solution, and then exposed to pressures less than the vapor pressure of sterilant. Both the exterior and interior surface areas of a lumen or non-lumen device can be effectively sterilized by taking advantage of the diffusion-restricted environments within lumens or within a container or enclosure.  
         [0041]     As used herein, a “diffusion-restricted” area refers to any one or more of the following properties: (1) the ability of the area of an article placed within the sterilization system of the present invention to retain 0.17 mg/L or more hydrogen peroxide after one hour at 40° C. and 10 torr; (2) having the same or more diffusion restriction than provided by a single entry/exit port of 9 mm or less in internal diameter and 1 cm or greater in length; (3) having the same or more diffusion restriction than provided by a lumen 27 cm in length and having an internal diameter of 3 mm; (4) having the same or more diffusion restriction than provided by a lumen having a ratio of length to internal diameter greater than 50; (5) the ability of an article placed within the sterilization system of the present invention to retain 17% or more of the starting 1 mg/L hydrogen peroxide solution initially placed therein after one hour at 40° C. and 10 torr; or (6) being sufficiently diffusion-restricted to completely sterilize a stainless steel blade within a 2.2 cm by 60 cm glass tube having a rubber stopper with a 1 mm by 50 cm stainless steel exit tube therein at a vacuum of 10 torr for one hour at 40° C. in accordance with the present invention. It is acknowledged that characteristics (1) and (5) will vary depending on the initial concentration of hydrogen peroxide placed into the article; however, this can be readily determined by one having ordinary skill in the art.  
         [0042]     This method includes the steps of contacting the exterior and interior of a device with a sterilant solution, and then exposing the device to a negative pressure or vacuum for a period of time sufficient to effect complete sterilization. For example, when 1 mg/L of hydrogen peroxide is used as sterilant, if the exposing step is conducted for 1 hour at 40° C. and 10 torr, the diffusion restricted area preferably retains 0.17 mg/L or more hydrogen peroxide, or retains 17% or more of the hydrogen peroxide placed therein after the exposing step. In certain preferred embodiments, the diffusion-restricted area has the same or more diffusion restriction than provided by a lumen 27 cm in length and an internal diameter of 3 mm, or has the same or more diffusion restriction than provided by a lumen having a ratio of length to internal diameter greater than 50. The contacting step can be performed by either a direct or an indirect contact procedure. Direct contacting includes methods such as injection, static soak, flow-through, condensation of a vapor, or aerosol spray, or mist spray. Any other methods involving physically contacting the devices to be sterilized with a sterilant would be considered direct contacting. Indirect contacting includes those methods in which sterilant is introduced into the chamber or container, but not directly on or on the devices to be sterilized. The exposing step is preferably performed for 60 minutes or less, and is preferably performed at a pressure less than the vapor pressure of the sterilant. Thus, the preferred pressure range under conditions of the present invention is between 0 and 100 torr. The exposing step can include the step of heating the device, such as by heating the container in which the exposing step occurs. The container can be heated to about 40° C. to about 55° C. Alternatively, the sterilant solution can be heated, such as to a temperature of about 40° C. to about 55° C. Optionally, the step of exposing the device to a plasma can be conducted during the step of exposing the device to negative pressure or vacuum. In one embodiment employing exposure to plasma, the method is performed within a first chamber and the plasma is generated in a second separate chamber. This embodiment further comprises the step of flowing the plasma into the first chamber. Advantageously, the contacting and/or exposing steps of the method can be repeated one or more times.  
       Method Based on Controlled Pump-Down Rate  
       [0043]     The cleaning/sterilizing process of the present invention can also be carried out in cooperation with a controlled pump down method without relying on a diffusion-restricted environment.  
         [0044]     Effective sterilization results similar to those created in diffusion-restricted environments can be created through controlling the evacuation rate of a chamber or container in which devices to be sterilized are placed. Thus, in one embodiment of the present invention, this controlled pump-down rate method comprises the steps of contacting the device with a liquid sterilant at a first pressure; draining excess liquid sterilant to retain a predetermined amount of the sterilant, and decreasing the pressure of the chamber to a second pressure below the vapor pressure of the liquid sterilant in which at least a portion of the decrease in pressure below about the vapor pressure of the liquid sterilant occurs at a pump down rate of less than 0.8 liters per second, calculated based on the time required to evacuate the chamber from atmospheric pressure to 20 torr when the chamber is empty and dry, i.e. when the chamber has neither devices to be sterilized nor a visible quantity of liquid within it. According to one aspect of this preferred embodiment, at least the decrease in pressure below about two times the vapor pressure of the liquid sterilant occurs at a pump down rate of less than 0.8 liters per second. According to another embodiment, the decrease in pressure below about four times the vapor pressure of the liquid sterilant occurs at a pump down rate of less than 0.8 liters per second. Preferably, the pump down rate is 0.6 liters per second or less; more preferably, 0.4 liters per second or less; and most preferably, 0.2 liters per second or less. Advantageously, the first pressure is atmospheric pressure. Preferably, the liquid sterilant is hydrogen peroxide. The hydrogen peroxide usually is a solution as used in the art, preferably it is a 3-60% solution. The device can be a lumen or non-lumen medical instrument.  
         [0045]     The present invention can also incorporate a method for sterilizing a device comprising the steps of (a) contacting the device with liquid sterilant at a first pressure; (b) retaining a predetermined amount of the liquid sterilant in the container; (c) pumping down the container or chamber to a second pressure which is lower than the first pressure at a first rate; and (d) pumping down the container or chamber to a third pressure which is lower than the second pressure, wherein at least a portion of the pumping down to the third pressure is at a second rate which is slower than the first rate. The pump down rate either above and/or below the second pressure can be constant or variable. In certain embodiments, the pump down rate either above and/or below the second pressure is reduced in stepwise fashion. Preferably, the second pressure is greater than or equal to about the vapor pressure of the liquid sterilant; more preferably, the second pressure is greater than or equal to about two times the vapor pressure of the liquid sterilant; most preferably, the second pressure is greater than or equal to about four times the vapor pressure of the liquid sterilant. Advantageously, the pump down rate in step (d) is 0.8 liters/sec or less; more advantageously 0.6 liters/sec or less; even more advantageously 0.4 liters/sec or less; and most advantageously 0.2 liters/sec or less, calculated based on the time required to evacuate the chamber from atmospheric pressure to 20 torr under empty and dry conditions. Preferably, the liquid sterilant is hydrogen peroxide. In another embodiment, the device is a medical instrument having a lumen. Preferably, the pumping down of step (c) reduces the pressure to less than about three times, more preferably to less than about two times, the vapor pressure of the liquid sterilant.  
         [0046]     Another suitable method includes contacting the device with liquid sterilant, retaining a predetermined amount of the liquid sterilant in the container, and reducing the pressure of the chamber while regulating the pump down rate so as to control the evaporation rate of sterilant in the chamber. In any of the methods described above, the contacting step may comprise application of liquid or condensed vapor. These methods described above may additionally comprise further evacuating the chamber to remove residual sterilant. Further, these methods described above may additionally comprise exposing the device to plasma to remove residual sterilant or enhance sterilization efficacy. The contacting step in these methods can be either by direct or indirect contacting. As stated herein, indirect contacting involves introducing sterilant into the chamber without directly contacting the device to be sterilized.  
       Two Step Pump-Down Method  
       [0047]     A two step pump down sterilization method can also be used in cooperation with the cleaning/sterilizing process of the present invention. This method comprises the steps of contacting a device with liquid sterilant; draining excess liquid sterilant to retain a predetermined amount of the sterilant; bringing the pressure of the chamber to a first pressure range at which the liquid sterilant is vaporized from non-diffusion restricted area of the device to sterilize the non-diffusion restricted area; bringing the pressure of the chamber to a second pressure range at which the liquid sterilant is vaporized from diffusion restricted area of the device to sterilize the diffusion restricted area, wherein the minimum pressure in the second pressure range is lower than the maximum pressure in the first pressure range.  
         [0048]     Preferably, the first pressure range is from 20 to 760 torr; more preferably, the first pressure range is 20 to 80 torr; most preferably, the first pressure range is 40-50 torr. Advantageously, the second pressure range is 1-30 torr; more advantageously, the second pressure range is 5-10 torr. In one preferred embodiment, the device includes a diffusion-restricted environment. Preferably, the device is a medical instrument with a lumen. Advantageously, the sterilant is hydrogen peroxide. According to another aspect of this preferred embodiment, the chamber is at a set temperature and wherein the first pressure is preferably lower than the vapor pressure of the sterilant at the set temperature. Preferably, the pressure of the chamber is maintained constant at the first pressure for a time period sufficient to sterilize the non-diffusion restricted area. Advantageously, the pressure of the chamber is maintained constant at the second pressure for a time period sufficient to sterilize the diffusion restricted area. The pressure of the chamber may be permitted to increase after reaching the first or second pressure range as a result of vaporization of the sterilant within the chamber. Alternatively, the pressure of the chamber is permitted to decrease after reaching the first or second pressure through pumping of the chamber at a rate slower than used to decrease the pressure between the first and second pressure ranges. Preferably, the contacting step is with liquid, condensed vapor, or mist. The method can also include the steps of bringing the pressure to a third pressure lower than the second pressure to remove residual sterilant and/or exposing the device to plasma to remove residual sterilant or enhance sterilization efficacy.  
       Method Involving Direct Flow Through a Lumen of the Device to Be Sterilized  
       [0049]     A method of directly flowing fluid through a lumen of a medical device to be treated can be incorporated with the cleaning/sterilizing or cleaning/disinfecting process of the present invention. An apparatus can be used to efficiently clean and sterilize devices with long narrow lumens by flowing a fluid such as a cleaning solution or a sterilant, either in liquid phase or in vapor phase, or a plasma gas directly through the lumens of lumen devices to be sterilized.  
         [0050]     The flow of a germicide (solution or vapor), or any cleaning solution through a lumen of a medical device is driven by a pressure drop between two open ends of the lumen. The pressure drop can be generated by applying either a vacuum or a high pressure at one end. By generating a forced flow through a pressure differential other than relying on diffusion, the sterilization rate is significantly increased and less time is needed for a sterilization cycle.  
         [0051]     It is clear that the two ends of the lumen need to be exposed to a pressure differential. This is achieved in the present invention by placing a sealable interface between two chambers, two enclosures, or a container and an enclosure to separate them from each other. Preferably, an opening is provided in the interface and the lumen device to be sterilized is placed through the opening so that the lumen serves as a flow path between the two chambers or between the container and the enclosure.  
         [0052]     The opening can be constructed in several ways. One way to achieve this is with a camera shutter approach employing an iris diaphragm, such as a precision iris diaphragm from Edmund Scientific. An optional spring can be used to secure the closure of the shutter. Also commercially available is Syntron Iris Flow Control Valve manufactured by FMC Corporation. This Iris Valve has a sleeve made of Teflon or other synthetic material defining an aperture. By rotating two ends of the sleeve relative to each other, the aperture can be reduced or increased. Iris diaphragm valves from Kemutec Inc. are also commercially available which can be automatically controlled. Another example is the AirGripper and AirPicker manufactured by Firesone Industrial Products Company. Another way to construct an openable and closeable opening is to employ two plates. Two edges of the two plates form a gap which can be adjusted by moving the two plates relative to each other. One or more lumen devices are placed through the gap formed between the two plates and the two plates are moved together to form a seal around the lumen devices. The edges of the two plates forming the gap can be equipped with compressible material or expandable material. When expandable material is used, a fluid source can be provided to expand the expandable material. Optionally, a porous material like a sponge or air permeable material may be utilized on the edges. In this case some sterilant can diffuse through the porous material to the outer surface of the lumen device occluded by the closed opening. However, most the sterilant flows through the lumen device. Another usable interface is a hole or a slot, the hole or slot is equipped with gas or liquid inflatable material so that by inflating the inflatable material on the hole or the slot the opening is reduced and the lumen device is held and sealed. Still another option is to place a compressible material on top of an expandable or inflatable material so as to facilitate the sealing around the lumen device.  
         [0053]     The closing and opening movement of the opening can be controlled mechanically or electronically with any conventional mechanism. The degree of opening is adjustable. Thus, it can be sealed to a different degree between the opening and the lumen device depending on the desired purpose. For example, the opening can form a gas-tight seal, a tight-fitting seal, or a loose-fitting seal around the lumen device. As used herein, a gas-tight seal refers to a seal that substantially stops liquid and gas flow through the contact area between the opening and the lumen device surface. When a gas-tight seal is employed, preferably the device to be sterilized is first pre-cleaned so that the occluded area by the seal is cleaned before the gas-tight seal is formed. A loose-fitting seal allows both liquid and gas to flow through the gap between the opening and the lumen device surface, and in the meantime is able to maintain a pressure drop across the interface enough to generate a flow through the lumen. A tight-fitting seal allows gas and liquid to penetrate to the contact area between the opening and the lumen device surface by diffusion. For example, a tight-fitting seal can be formed with porous material or textures provided on the contact surface of the opening. Thus, for gas-tight seal the device is held tightly by the closed opening. In the tight-fitting seal, the closed opening also holds the device in position. In the case of a loose-fitting seal, the device can move relative to the opening, but is not flashed away.  
         [0054]     The interface can be made openable, closeable, and removable, and may have more than one opening. In order to promote sterilization efficiency, all the sterilization apparatus of the present invention can be further equipped with a heater and/or a plasma.  
       Specially Designed Containers  
       [0055]     As used herein, the terms “container” and “enclosure” are exchangeable. The present invention provides a container specially designed to eliminate or minimize occlusion area which usually corresponds to the contact area between a lumen device surface and a closed opening of an interface holding the device. The occlusion area is hard to reach by either liquid or vapor because of the close contact between two surfaces. Thus, the cleaning and sterilizing of an occlusion area is adversely affected by such contact. Several approaches have been taken in the present invention to deal with this occlusion problem.  
         [0056]     One approach is to reduce the contact area by using porous material, textures, sharp projections, or sharp edges on the contact surface of the opening of the interface, or an adaptor or a connector. In this way, cleaning and sterilizing fluid can either flow or diffuse to most part of the contact surface of the device which is held by the closed opening fairly tightly and, in the meantime, the contact area between the opening and the device surface will impose a resistance to fluid flow high enough to allow a pressure difference to exist between two sides of the interface. Thus, a flow through the lumen of the device can be generated and maintained if desired. Another advantage of this approach is that the contract area generated through the above means can be controlled to provide a diffusion restricted environment at the contact area, which will increase the efficiency of the sterilization process.  
         [0057]     Another approach is to use multiple holders in the opening. For example, two holders can be secured to the opening along its passage. Preferably, each of the holders is independently controllable and sealable. During a cleaning or sterilizing process, the two holders are alternately opened and closed, i.e. one is open while the other is close. In this way, a good seal between the two sides of the interface can be maintained and the device can be held tightly during a sterilization process. Meanwhile, the contact areas on the device surface caused by the two holders are exposed to cleaning or sterilizing fluid alternately.  
         [0058]     Still another approach is the combination of the above two approaches. In this approach, the contact surface of the interface, or the opening, or the holder has multiple contact points. The contact points can be projections, teeth, blades, sharp edges, or any other suitable form and shape. These contact points can be controlled separately so that a portion of the contact points is made in contact with the device to be sterilized while the others are not. By alternately changing the position of the contact points, all the occlusion areas will be exposed to the sterilant. An example of such a multiple contact point structure is a shutter with multiple blades. Those blades can be separately controlled for opening and closing.  
         [0059]     The present invention also provides a container with a specially designed tray. It is often desirable to place the device to be sterilized on a tray so that after the device is cleaned and sterilized, it can be transported on the tray without being touched. This reduces the chance of contamination through touching the device. In the apparatus of the present invention, a tray is placed across an openable and closeable interface between a container and an enclosure or between two compartments or enclosures, a lumen device is placed on the tray also across the interface. When the interface is in a closed condition, a seal is formed between the opening of the interface and the tray and the lumen device.  
         [0060]     Various apparatus of the present invention which can be used to carry out the cleaning/sterilizing or cleaning/disinfecting process of the present invention is described in more detail by reference to the drawings. In the following figures like numbers refer to like parts throughout.  
         [0061]      FIG. 1   a  shows a container  2  used in a cleaning/sterilizing process of the present invention. Container  2  has a sloped bottom wall  4  leading to a fluid source  7 . A fluid port  6  is provided at the lowest point of sloped bottom wall  4 . Apparently, sloped bottom wall  4  can be configured differently and the lowest point can be located in any location within the sloped bottom wall  4 . For example, instead located in the position as shown in  FIG. 1   a,  the lowest point, thus the fluid port  6 , can be located at one end or a corner of the sloped bottom wall  4 . A valve  8  is provided at fluid port  6  to control fluid flow in and out container  2 . Below sloped bottom wall  4  is a flat lower bottom  14 . The lower surface of the sloped bottom wall  4  is equipped with a number of transducer  16  for providing ultrasonic cleaning. A number of wells  18  are provided on a plate  17  located above the upper surface of the sloped bottom wall  4  and below rotating arm  22 . Plate  17  can be of any appropriate shape and made rotatable, so that unwanted liquid retained in wells  18  can be removed by rotating plate  17 . Well  18  can have different shapes and is capable of retaining a predetermined amount of sterilant as described earlier. Plate  17  can be removably placed on the upper surface of the sloped bottom wall  4  or secured to the upper surface in a horizontal orientation. One or more stirrer  20  is installed either on sloped bottom wall  4  or on an upper wall  24  or on both. Rotating arm  22  of the stirrer  20  can be made hollow or contains channels connecting to an outside fluid source through the body of the stirrer  20 . As shown in  FIG. 1   b,  stirrer  20  can be connected to a water source  21   a,  an air source  21   b,  and a drain  21   c,  each of them is controlled by a valve. Water jet or air jet  26  can be provided through the channels of rotating arm  22 . Container  2  can also be made of jacket walls with holes thereon so that the water or air jet can be provided through those holes opened on the jacket walls. Container  2  also has a lower grid  28   a  and an upper grid  28   b.  Preferably, grid  28   a  and  28   b  has a flat shape and horizontally placed inside container  2  at an upper and a lower position, respectively. A space defined by lower grid  28   a,  upper grid  28   b  and side walls of container  2  is used to accommodate a device to be treated. A tray  30  can be placed in the space and the device is placed in the tray  30  for cleaning and sterilizing. Stirrer  20  is located either in the space defined by upper wall  24 , upper grid  28   b  and side walls of container  2 , or in the space defined by sloped bottom wall  4 , lower grid  28   a  and side walls of container  2 , or in both. Container  2  further contains a vacuum port  32  located at the upper portion of container  2 . Preferably, vacuum port  32  is located on the upper wall  24  of container  2  to avoid liquid in container  2  from entering vacuum port  32 . A gas-permeable but microorganism-impermeable barrier  34  is secured to the vacuum port  32 . Any conventional method can be used to seal barrier  34  into vacuum port  32  such as shown in  FIG. 1   c.  In the connection shown in  FIG. 1   c,  barrier  34  is placed in a barrier holder  34   a.  The barrier holder  34   a  is placed into a seat  34   b  formed between two end of two tubes. An O-ring  34   c  is provided around holder  34   a.  Thus, by clamping the two ends of the two tubes toward each other barrier  34  is secured and sealed. A valve  36  is provided at vacuum port  32 . A vacuum pump  38  is connected to vacuum port  32  through valve  36 . A detachable connector can be provided between valve  36  and vacuum pump  38 .  
         [0062]     Container  2  of  FIG. 1   a  can be placed into a vacuum chamber with slight modification. As shown in  FIG. 1   d,  the same container  2  is used except that barrier  34  provided on upper wall  24  is not connected directly to the vacuum port  32  which is provided on the wall of a vacuum chamber  66 .  
         [0063]      FIG. 1   e  shows another way of providing a fluid jet in container  2 . Instead of stirrers, several tubes  22   a  with small holes thereon are secured vertically in container  2  to provide a fluid jet such as a water jet or an air jet. Tube  22   a  can be positioned to provide an uniform spray, the orientation and shape of tube  22   a  can be determined according specific purposes. The rest parts can be the same as the container of  FIG. 1   a.    
         [0064]     When using the above described container in the cleaning/sterilizing process of the present invention, one first places a device into the container  2 . The device can be either placed on the lower grid  28   a  or placed in tray  30 . Two grids  28   a  and  28   b  set the boundaries for the devices in the container and keep the device from being damaged by stirrer  20 . The upper grid  28   b  is the fluid fill line to ensure all the devices are immersed in the fluid. Usually the device is first pre-cleaned in container  2  by a water jet to remove majority of soils, large particles, and other contaminates. During the pre-cleaning, the drain is usually kept open to remove the dirty water containing those particles and contaminates. Then the device is cleaned. In this step a cleaning solution is filled into container  2  through a liquid pump. The cleaning solution can be any conventional cleaning solution with enzyme and detergent solution preferred. During the cleaning step, stirrers, water jet, ultrasonics, or other suitable mechanism can be used to facilitate the cleaning process. When the cleaning is complete, the cleaning solution is drained through fluid port  6 . A rinse solution is then introduced into container  2  through fluid port  6 . The rinse solution can be water, alcohols, or other rinse liquid. The rinsing can be facilitated by stirrers, water jet, air bubbles, or other suitable mechanism. These steps can be repeated if desirable. After the rinsing step, air can be introduced through stirrer  20  to blow water off the device. Then a liquid sterilant is introduced into container  2  from the same fluid port, and the device is treated with the liquid sterilant for a desired time. Preferably, the liquid sterilant is a hydrogen peroxide solution or a peracetic acid solution. The main purpose of this step is to treat the device with the liquid sterilant and to provide right amount of the liquid sterilant. The sterilization is achieved mainly in next step. If necessary, excess of the liquid sterilant can be drained from container  2 , and a predetermined amount of the liquid sterilant will be retained by the wells  18 . This amount of liquid sterilant is determined based on the size of the load, the container, and the vacuum chamber. At this point, vacuum pump  38  is turned on and vacuum is applied to container  2  through vacuum port  32 . In this step, the diffusion restricted environment method, the controlled pump down rate method, the two step pump down method discussed previously can be employed to achieve good sterilization results. When the sterilization is finished, container  2  is detached from the vacuum system, the device can be kept in container  2  and stored for future use. The sterility of the sterilized device is maintained in container  2  because container  2  is sealed except for the gas-permeable but microorganism-impermeable barrier  34 . In one embodiment, valve  36  is closed when the pressure in container  2  is lower than atmospheric pressure and container  2  including the sterilized device is stored for use. This procedure provides a further means to check if the sterility of the device is well maintained in the container. If the container  2  is still under a pressure below the atmosphere before next use of the device, that means no air leaking into container  2  and, thus, no microorganism can enter container  2  during the storage. Any one of the above steps can be repeated if desirable. The sterilizing step can also be replaced with a disinfecting step by using a proper germicide.  
         [0065]      FIG. 2  shows a container having adapters for connecting lumen devices. Similar to the container of  FIG. 1   a,  container  2  shown in  FIG. 2  has a sloped bottom wall  4  with a first fluid port  6  at the lowest point of the sloped bottom wall  4 . Several stirrers are installed on the sloped bottom wall  4 . A flat sheet metal grid  28   a  is horizontally located at the lower portion of container  2 . Grid  28   a,  sloped bottom wall  4 , and side walls of container  2  define a space accommodating stirrer  20  and wells  18  on plate  17 . An adapter  40  is connected to a second fluid port  42  at one end and the other end for receiving a lumen device  46 . A gas-tight seal, tight-fitting, or loose-fitting between adapter  40  and lumen device  46  can be formed. Adapter  40  can be any suitable conventional adapters used in the art. Preferably, the second fluid port  42  is located above grid  28   a.  Second fluid port  42  is also connected to a source  44  for generating a pressure difference between the two ends of a lumen device  46  which is connected with the second fluid port  42  through adapter  40 . Source  44  can be a liquid pump for generating negative pressure, or a positive pressure. Lumen device  46  is placed on top of the grid  28   a.  Like the container shown in  FIG. 1   a,  container  2  of  FIG. 2  also has a vacuum port  32  with a gas-permeable but microorganism-impermeable barrier  34  and a valve  36 . The barrier covers the vacuum port  32  and blocks passage for microorganism, valve  36  controls the opening and closing of the vacuum port  32 . As shown, fluid port  6  and stirrers  20  are also connected with a tube  9  for draining fluid from container  2  or supplying fluid jet to stirrer  20 . One end of tube  9  leads to a waste fluid collector, the other end is connected to pump  44 .  
         [0066]      FIG. 3   a  shows a container  2  separated into a first enclosure  50   a  and a second enclosure  50   b  by an interface  52 . As shown both enclosure  50   a  and  50   b  have a sloped bottom wall  4  with stirrer  20  secured thereon, a flat sheet grid  28   a  horizontally positioned at lower portion of enclosure  50   a  and  50   b,  and a fluid port  6 , respectively. A pump  54  is provided between the two fluid ports  6 . A vacuum port  32  is provided at the upper portion of enclosure  50   a  and  50   b.  A gas-permeable but microorganism-impermeable barrier  34  is connected to the vacuum port  32  to stop microorganism from entering enclosure  50   a  and  50   b  through vacuum port  32 . Vacuum port  32  is also equipped with a valve  36  and a source  44  for generating pressure difference and providing vacuum. Preferably, source  44  is a vacuum pump for providing negative pressure or compressed air for providing positive pressure. Interface  52  has a controllable opening  56  (also referred as holder). Lumen device  46  is placed across opening  56  partly in enclosure  50   a  and partly in enclosure  50   b.  Opening  56  can be configured differently. For example, opening  56  can be made of a shutter  58  such as an iris diaphragm as shown in  FIG. 3   b,  and the opening and closing of opening  56  can be controlled manually or automatically. In one embodiment, the blades of shutter  58  (eight blades are shown in  FIG. 3   b ), can be divided into two groups. For example, each group contains four blades not next to each other. These two groups of blades are controlled separately by a controller so that while one group is in the close position holding the device to be sterilized the other group is in open position allowing the sterilant to sterilize the area occluded by the blades when the blades are in closed position. Another example of shutter  58  is the Syntron Iris Flow Control Valve (by FMC Corporation) or the Iris diaphragm valves (Kemutec Inc.) as shown in  FIG. 3   c.  Briefly, Iris valve  58   a  has a cylindrical sleeve  90  with two retaining rings  92  located at two ends of the cylindrical sleeve  90 . Sleeve  90  is made of Teflon or other suitable plastic or rubber material. When in use, a lumen device is inserted through an aperture  94  of cylindrical sleeve  90 . A first retaining ring  92  is secured and sealed to opening  56 , a second retaining ring  92  is free to rotate and coupled to interface  52  through a conventional mechanical mechanism (not shown) so that the turning of the second retaining ring  92  can be controlled mechanically or electronically from outside container  2 . By rotating the retaining rings  92  relative to each other, the diameter of aperture  94  of the cylindrical sleeve  90  can be increased or reduced, or totally shut off. If desirable, more than one shutter can be provided in the interface  52 .  
         [0067]     Opening  56  also can be a slot or a gap defined by two plates  59  as shown in  FIGS. 3   d  and  3   e.  The contact edges or surfaces of plate  59 , which form the slot and hold the lumen device  46 , are equipped with a layer of expandable material  60  such as silicon, or a layer of compressible material  62 . The closing, and thus seal around lumen device  46 , of the slot can be done either by moving plate  59  or expanding expandable material  60 . With a two-plate opening  56 , more than one lumen device can be placed across the opening  56 . When expandable or inflatable material is used on plate  59 , an expansion fluid source can be provided to plate  59  to expand the expandable material  60 . In one embodiment, a layer of compressible material  62  is provided on top of the layer of expandable material  60  as shown in  FIG. 3   f.  In another embodiment, the opening  56  is formed by an upper plate  59   a  and a lower plate  59   b  as shown in  FIG. 3   g.  The lower plate  59   b  has a rectangular shape with a bottom edge and two side edges being secured and sealed to the bottom wall and two side walls of container  2 , respectively. The upper plate  59   a  also has a rectangular shape and its upper portion is movably inserted into a housing  53   a.  Housing  53   a  forms the upper portion of interface  52 . A portion of housing  53   a  extends along two side walls of container  2  to the upper edge (or contact surface) of lower plate  59   b,  forming two rails  53   b  for receiving the two side edges of upper plate  59   a  and guiding the movement of the upper plate  59   a.  There provided a seal between the upper plate  59   a  and the housing  53   a  and rail  53   b.  For example, an O-ring can be used in housing  53   a  and rail  53   b  to seal the upper plate  59   a.  The upper edge of the lower plate  59   b  and the lower edge of the upper plate  59   a  are provided with a layer of compressible or expandable material. The movement of the upper plate  59   a  can be controlled by any suitable conventional method, mechanically or electrically, form the outside of container  2 . Many different configurations and structures can be adopted for the opening  56 . For example, the contact surface of opening  56  can be made of an uneven surface so that, when opening  56  is closed around a lumen device, the uneven surface will provide passage to allow both liquid and gas to pass therethrough while holding the lumen device. Thus, the occlusion area on the lumen device surface can be significantly reduced. The uneven surface may have textures, projections, sharp edges, or sharp points thereon.  
         [0068]     In another embodiment, opening  56  is an aperture equipped with a layer of porous material or with a layer of expandable material and a layer of porous material on top of the expandable material. Opening  56  also can be made of an aperture of suitable shape, such as cylindrical, lined with porous material. A shutter is secured to the aperture providing a steady holding of the lumen device  46  with minimal contact area or occlusion area.  
         [0069]      FIG. 4  shows a container  2  with an enclose  50  separated by an interface  52 . In this embodiment, the container  2  with the enclosure  50  is placed inside and coupled to vacuum chamber  66 . Vacuum chamber  66  has a first vacuum port  68  which is in gas communication with container  2  through a gas-permeable but microorganism-impermeable membrane  34  installed on the upper wall of container  2 , and which is preferably located at the upper portion of a side wall of vacuum chamber  66 . A valve  35  is provided above membrane  34  to control the opening and closing of gas communication of container  2  with outside through membrane  34 . Vacuum chamber  66  also has a second vacuum port  70  connecting to a vacuum port  32  of the enclosure  50  through a valve  36 . Preferably, the second vacuum port  70  also located at the upper portion of the side wall of the vacuum chamber and near the first vacuum port  68 . Valve  36  is preferably located outside the enclosure  50  and inside the vacuum chamber  66 . A detachable connector (not shown) is preferably provided between valve  36  and second vacuum port  70  for attaching valve  36  to and detaching valve  36  from the second vacuum port  70 . The first and second vacuum ports  68  and  70  are connected to each other outside the vacuum chamber  66 . A valve  72  is provided at first vacuum port  68  to control flow through the first vacuum port  68 . A valve  74  can also be provided at the common inlet of the first and second vacuum ports  68  and  70 . A source  44  for generating pressure difference between the two ends of the lumen device  46  is provided at the common inlet of first and second vacuum ports  68  and  70 . Preferably, source  44  is a vacuum pump for generating a negative pressure or compressed air for generating a positive pressure. Vacuum chamber  66  also has a first fluid port  76  connecting to a fluid port  6   a  of the container  2  through a valve  8   a,  and a second fluid port  78  connecting to a fluid port  6   b  of the enclosure  50  through a valve  8   b.  The first and second fluid ports  76  and  78  are located at the lower portion of a side wall of the vacuum chamber  66  and close to each other. The fluid port  6   a  is located at the lowest point of a sloped bottom wall  4   a  of the container  2 . In this embodiment, the fluid port  6   a  is located at one lower corner of the container  2 . The fluid port  6   b  is located at the lowest point of a sloped bottom wall  4   b  of the enclosure  50 . In this embodiment, the fluid port  6   b  is located at one lower corner of the enclosure  50 . A detachable connector can be provided for connecting valve  8   a  and  8   b  to first and second fluid port  76  and  78 , respectively. Outside the vacuum chamber  66 , first and second fluid ports  76  and  78  are connected to each other forming a common fluid inlet which is provided with a valve  80 . A liquid pump  54  is also provided between the first and second fluid ports  76  and  78  to circulate a fluid between the container  2  and the enclosure  50 . The container  2  has a lower grid  28   a  and an upper grid  28   b.  Preferably, the lower grid  28   a  and the upper grid  28   b  are a flat metal sheet and horizontally positioned at the lower and the upper portion of the container  2 , respectively. Stirrers  20  are located below the lower grid  28   a.  Interface  52  has an opening (or holder)  56  for holding a lumen device  46 . The opening  56  can be configured in many different ways such as those described with  FIGS. 3   b - 3   f.  On the bottom wall of vacuum chamber  66 , a plurality of transducer  16  is provided to generate ultrasonics. Accordingly, the space between outer surface of the bottom of container  2  and the inner surface of the bottom wall of vacuum chamber  66  is filled with water or other suitable liquids providing a medium for the ultrasonics.  
         [0070]     In using the apparatus with containers and enclosures separated by an interface in the cleaning/sterilizing or cleaning/disinfecting process of the present invention, a lumen device is placed into the container  2  and the enclosure  50  across the interface  52 . The opening  56  of the interface  52  is then closed manually or automatically. Thus, opening  56  forms a seal around the lumen device. The extent of the sealing can be controlled through different degree of tightening of the opening  56  around the lumen device  46  for different purposes. As defined previously, three types of seal can be made between the opening  56  and the lumen device  46 , gas-tight seal, loose-fitting seal and tight-fitting seal. If maximum pressure is intended a gas-tight seal should be used in this case the container  2  is substantially totally sealed from the enclosure  50 , neither gas nor liquid can flow through the space between the opening  56  and the lumen device  46 . Under many situations such a gas-tight seal is not necessary. In this case, a tight-fitting seal can be used so that a portion of fluid in the system can flow or diffuse through the space between the opening  56  and the lumen device  46 , but a large portion of the fluid flows through the lumen of the lumen device  46 , and the lumen device  46  is still held in position by the opening  56  during agitation. Loose-fitting will provide a opportunity to clean/sterilize the outer surface area of the lumen device  46  which is otherwise obscured by the opening  56 .  
         [0071]     A cleaning solution is then introduced into the container  2  and the enclosure  50  through fluid port  6   a  and  6   b,  respectively. The liquid level in the container  2  and the enclosure  50  is preferably not higher than the position of the vacuum port  32 . A stirrer, a water jet or an air jet can be used to facilitate the cleaning of the outer surface of the lumen device  46 . The cleaning solution is also circulated between container  2  and enclosure  50  through the lumen of the lumen device  46 . There are at least two ways to make the circulation. One method is to apply vacuum to the enclosure  50  through second vacuum port  70  of vacuum chamber  66  and vacuum port  32  of the enclosure  50  while keeping vacuum chamber  66  and container  2  at atmospheric pressure or any pressure higher than that of the enclosure  50 . This can be done similarly when vacuum chamber  66  is not used. The cleaning fluid then flows from the container  2  into the enclosure  50  through the lumen device  46 . The liquid pump  54  circulates the cleaning fluid back to the container  2 . The opening  56  and the stirrer  20  can be controlled by the electronic signals from the system. Air bubbles generated from air pump  10  can be introduced at this stage to enhance the scrubbing action during cleaning. Thus, both the outer surface and the inner surface of the lumen device  46  can be cleaned at the same time. Vacuum can be applied to container  2  to generate a pressure in the container  2  lower than that of the enclosure  50 . Forced air also can be used to push liquid through the lumen. If desired, the interior and the exterior of the lumen device can be cleaned separately. The cleaning fluid can be removed from the container  2  and enclosure  50  through the fluid port  6   a  and  6   b  on the sloped bottom wall  4   a  and  4   b.  The cleaning fluid in the lumen device  46  can be removed either with vacuum or forced-air.  
         [0072]     The rinsing with water and the treatment with liquid sterilant can be conducted similarly. When the treatment with a liquid sterilant is complete, the liquid sterilant is drained and a predetermined amount of the liquid sterilant can be retained in the wells. Then vacuum is applied to chamber  66  and container  2  either through vacuum port  68  or  70 , or both in a manner described earlier. At least in certain stage, the vacuum should be high enough (or the pressure low enough) to vaporize the remaining sterilant in container  2  to sterilize and dry the device simultaneously. A plasma can be used as an option to enhance the efficacy and/or to remove the sterilant residual. After the sterilization is completed, the chamber is vented and the container is ready to be retrieved from the chamber. If desired, valve  35  can be closed at any pressure below the atmospheric pressure and the sterilized device is kept in container  2  under a subatmospheric pressure. This may serve as an indication of a well maintained sterility, i.e. if the vacuum still exists when container is opened after a period of time of storage that indicates the sterility of the sterilized device is well kept. The pressure can be monitored and controlled by the pressure sensor on the vacuum chamber  66  or in container  2 .  
         [0073]      FIG. 5   a  shows a container very similar to that shown in  FIG. 3   a  except that two holders  100  are used in opening  56  of interface  52 . As shown in  FIGS. 5   a  and  5   b,  the two holders  100  are secured to opening  56  along lumen device  46  or the passage of opening  56 . Each holder  100  is sealed to opening  56  in any suitable conventional manner and each holder  100  is independently controllable. Holder  100  can be a shutter as the shutter described with  FIGS. 3   b  and  3   c,  or made of two plates as described with  FIGS. 3   d - 3   g .  FIG. 5   b  shows two holders  100  of shutter type holding a lumen device  46 . During cleaning or sterilizing operation, a first holder  100  is first closed and a second holder  100  is opened, then the first holder is opened and the second holder  100  is closed. Thus, enclosures  50   a  and  50   b  are always separated or insulated from each other through the engagement of one holder  100  with the device  46  and, in the meantime, the two contact surface areas of the device  46  occluded by the two holders  100  are exposed alternately.  
         [0074]      FIG. 5   c  shows two holders  100  of plate type holding a lumen device  46 . Each of holders  100  can be constructed in the way as described previously with  FIGS. 3   d - 3   g . Preferably, the gap (the opening for passing the lumen device) formed between the two plates of one holder  100  forms an angle with that of the other holder  100  of the two holder structure. Preferably, the angle is 90 degree as shown in  FIG. 5   c.  The two holders  100  are preferably positioned close enough so that when the expandable material  60  lined in the gap (opening) is expanded, the expandable material  60  will also expand outwardly away from the two plates and become in contact with the other holder  100 , thus help seal the gap of the other holder  100 . This configuration provides an advantage that no complete seal is needed for a single holder, yet a good seal such as a gas-tight seal can be achieved when two such holders are combined. It has been noted by the applicants that, when a cylindrical lumen device is placed across the gap between the two plates of holder  100 , areas on the outer surface of the lumen device, where the diameter of the cylindrical lumen device is parallel to the gap, are more difficult to seal because the expandable material  60  has to expand extra distance to cover those areas. By providing two closely positioned holders  100  with the two gaps forming an angle, the above mentioned areas in each of the two holders can be sealed by the other holder. Therefore, the requirement to the expandable material can be lowered without sacrificing the sealing characteristics.  FIG. 5   d  shows another embodiment of an interface of the present invention. In this embodiment, the interface  52  contains multiple openings  56   c.  This interface  52  may have three parts. A first plate  59   c  has a plurality of openings  56   c  thereon. The cross section of the opening  56   c  as viewed from a direction perpendicular to the surface of plate  59   c  has an elongate shape with its longitudinal axis extending along a substantially vertical direction. Other orientation also can be adopted. Preferably, opening  56   c  has a rectangular cross section. The upper side of the openings  56   c  can be made open for easy access to a lumen device. The contact surface of opening  56   c  is provided with a layer of expandable material  60 . A second plate  59   d  is positioned beside the first plate  59   c  in parallel. Plate  59   d  can be secured and sealed to the bottom and side walls of container  2  with its upper edge or surface equipped with a layer of expandable material  60 . A third plate  59   e  is located above and aligned with second plate  59   d.  The third plate can be made a part of the lid for container  2 . The lower edge of plate  59   e  and the upper edge of plate  59   d  form a gap for passing a lumen device. The edges of the third plate is also provided with a layer of expandable or other sealing material  60 . Preferably, the second plate  59   d  and the third plate  59   e  lie in one vertical plane, and the first plate  59   c  lies in another vertical plane parallel to that containing second plate  59   d  and third plate  59   e.  Preferably, the gap formed between plate  59   d  and  59   e  forms an angle with openings  56   c,  more preferably the angle is a right angle. In one preferred embodiment, the gap between second plate  59   d  and third plate  59   e  has a horizontal orientation, and the openings  56   c  have a vertical orientation. The distance between the first plate  59   c  and the second and third plate  59   d  and  59   e  can be adjusted depending on intended purpose. Preferably, they are closely positioned relative to each other so that when the expandable material  60  on one plate is expanded, it will become in contact with the other plate to further facilitate seal around the lumen device passing both the gap between plate  59   d  and  59   e  and the opening  56   c  of plate  59   c.  Preferably, the dimension and the expandable material layer of opening  56   c  is determined to allow the opening  56   c  to be closed and sealed when the expandable material is expanded even no lumen device is placed through the opening.  
         [0075]      FIG. 6  shows a container  2  has three enclosures  50   a,    50   b,  and  50   c  separated by two interfaces  52   a  and  52   b,  respectively. Enclosure  50   b  is located in between and shares interfaces  52   a  and  52   b  with enclosure  50   a  and  50   c.  Other parts of the container  2  of  FIG. 6  are similar to those of the container shown in  FIG. 3   a,  and they are indicated by same numerical references. Two openings  56   a  and  56   b  are located in interface  52   a  and  52   b , respectively. Opening  56   a  and  56   b  can be of any form as discussed previously. In practice of the process of the present invention, a lumen device  46  is placed across both opening  56   a  and opening  56   b  with one end located in enclosure  50   a  and the other end in enclosure  50   c.  The advantage of the configuration is to help obtain a large pressure drop between the two ends of the device  46 . Under certain circumstances, the seal between the opening and the lumen device may be not gas-tight, thus it is difficult to keep a large pressure drop at the two sides of the interface with such a seal. By adding one intermediate enclosure  50   b,  the pressure drop across each interface  52   a  and  52   b  can be kept at a relative low level, yet the total pressure between the two ends of the device  46  or, in other words, between enclosure  50   a  and enclosure  50   c  can be still large enough to generate desired flow rate through the lumen of the lumen device  46 . If desired, one interface  52   a  or  52   b  can be removed or opened, and in those cases the container  2  can be operated just like that of  FIG. 3   a.    
         [0076]      FIG. 7   a  shows a container  2  separated into an enclosure  50   a  and an enclosure  50   b  by an interface  52  similar to the container of  FIG. 3   a  except that a tray  110  is placed across interface  52  and located in both enclosure  50   a  and enclosure  50   b.  The tray  110  shown in  FIG. 7   a  has a rectangular shape with four side walls perpendicular to a bottom wall defining a space for receiving a lumen device  46 . The side and bottom walls have open holes thereon. As shown in  FIG. 7   b,  interface  52  can be configured to have two parts. The first part forms a tray seat  112  extending along an interior periphery of container  2 . Tray seat  112  has a first edge secured and sealed to the interior periphery of container  2  and a second edge  114  shaped to receive tray  110 . Edge  114  has a bottom portion and two side portions defining an open rectangular cross section. On top of edge  114  is a sealing layer  116  made of expandable, compressible, or other suitable material. When tray  110  is placed into container  2 , an exterior periphery of tray  110  will seat on edge  114  and layer  116 . The second part of interface  52  can be a removable plate  118  having an edge  120  shaped to fit the shape of an interior periphery of tray  110 . On top of edge  120  is a sealing layer  122  made of expandable, compressible, or other suitable material. Plate  118  is inserted into tray  110  along an interior periphery of tray  110 . A guide rail can be provided with tray  110  to guide plate  118  moving along an predetermined interior periphery. Different shapes can be used for edge  114  of seat  112  and edge  120  of plate  118 , as long as the shape matches that of the exterior and interior periphery of tray  110 . For example, in one embodiment, the open rectangular formed by edge  114  and edge  120  shown in  FIG. 7   b  is modified by making the upper edge longer than the bottom edge of the open rectangular and tray  110  has a corresponding shape. This configuration makes it easier to the plate  118  down into tray  110  and seal it. Plate  118  can further include an opening  56  of any kind as discussed previously with  FIGS. 3   b - 3   g.  Opening  56  can be located in plate  118  or on edge  120  facing the bottom of tray  110  where lumen device is placed. In one embodiment, a layer of expandable, compressible, or other suitable sealing material is also provided with tray  110  along the interior periphery where plate  118  is inserted.  FIG. 7   c  shows another embodiment in which tray  110  has a partition  111  therein. Partition  111  can be made as part of the tray  110 . Upper edge  111   a  of partition  111  has a layer of expandable, compressible, or other suitable sealing material. Partition  111  is aligned with plate  118  so that when plate  118  is inserted into tray  110  seal can achieved between upper edge  111   a  of partition  111  and lower edge of plate  118 , and a lumen device can be placed through the gap or opening  56  formed between upper edge  111   a  of partition  111  and lower edge of plate  118 . In one embodiment, in the contact area between tray  110  and interface  52  (or plate  112  and  118 ), a portion of side and bottom walls of tray  110  is removed so that in those portion the sealing layer  116  of tray seat  112  and the sealing layer  122  of plate  118  of the interface  52  are in direct contact. Plate  118  can be secured to a lid or cover  119  for container  2  and, a portion of the lower surface of the cover  119  is provided with a layer of expandable, compressible, or other suitable sealing material to seal the upper edge of the tray  110  and the container  2  as shown in  FIG. 7   c.    
         [0077]     When exposed to a pressure difference between enclosure  50   a  and  50   b,  tray  110  may be forced to move from high pressure side to low pressure side. In order to prevent this from happening, a stopper mechanism is provided. In one embodiment as shown in  FIGS. 8   a - 8   d  which are top views of container  2  and tray  110 , tray  110  has a rectangular bottom wall  130  with two side walls  132  along two longer edges of bottom wall  130  and two side walls  134  along two shorter edges of bottom wall  130 . There is an indentation on each side wall  132  extending along the entire height of side wall  132  and substantially perpendicular to bottom wall  130 . Container  2  also has a rectangular bottom wall  140  with two side walls  142  along the two longer edges of bottom wall  140  and two side walls  141  along two shorter edges of bottom wall  140 . There is a projection  144  on each side wall  142  extending along the entire height of side wall  142  and perpendicular to bottom wall  140 . The surface of projection  144  is covered with a layer of expandable, compressible, or other suitable sealing material  146 . The projection  144  has a shape matching that of the indentation  136 . When tray  110  is placed into container  2 , indentation  136  will engage with projection  146  so as to hold tray  110  in position. A tray seat  112  with a layer of sealing material on its upper surface is provided on bottom wall  140  of container  2  extending between two projections  146 . Tray  110  also has two edges  137  on each side wall  132  extending inwardly from indentation  136 . A removable plate  118  with a layer of sealing material on its contact edge is inserted into tray  110  through a rail defined by extruding edge  137 . In another embodiment, each side wall  141  is provided with a stopper, such as an extrusion, to confine the movement of tray  110  along a direction perpendicular to interface  52 .  
         [0078]      FIG. 9  shows a recycling system which can be incorporated into any container systems used in the present invention. In this system, used liquid in a cleaning/sterilizing process is drained or pumped to a reservoir  150  through a filter  152 . A pump  154  can be provided between reservoir  150  and fluid port  6  to help drain the used liquid into reservoir  150 . The filtered liquid in reservoir  150  can be then cycled back to container  2  through a fluid port  6   a.  If necessary, filter  152  can be cleaned by back flash. Reservoir  150  is also equipped with several inlets  156  for water, cleaning chemical, and sterilant, respectively, and a drain  158 .  
         [0079]     The present invention has been described above. Many modifications and variation of the cleaning/sterilizing or cleaning/disinfecting process and the apparatus in such process may be made without departing substantially from the spirit and scope of the present invention. Accordingly, it should be clearly understood that the form of the invention described and illustrated herein is exemplary only, and is not intended as a limitation on the scope.