WO2023131816A1

WO2023131816A1 - Device for viable/microbiological active air sampling with no removed lid (rotation discs lid) and its manufacturing method

Info

Publication number: WO2023131816A1
Application number: PCT/IB2022/050128
Authority: WO
Inventors: Ahmad AAMER; Mohamed AAMER
Original assignee: Aamer Ahmad
Priority date: 2022-01-09
Filing date: 2022-01-09
Publication date: 2023-07-13

Abstract

The invention generally provides a device and a method for active sampling and/or monitoring, of microbiological/ biological particles in air/gases in environments where the microbiological quality of air and/or gases is of concern, such as cleanroom environments in variety of industries, for example: pharmaceuticals, bio-pharmaceuticals and electronics manufacturing, e.g. facilities aseptic and/or non-aseptic environments. The invention allows for collection, growth and characterization of viable microbiological/biological particles. The invention incorporates a device that is designed to be connected to an air sampling device/pump for collecting and/or analyzing microbiological/biological particles in air, gases. The device of the current invention incorporates a plate of integrated upper part (A) designed with rotating discs to avoid lid removal, and a lower part (B) of more than one compartment that includes the receiving surface of a growth/culture medium. The invention offers the simplest way of conducting active air sampling and eliminate risks associated with false positive contamination of the impaction surface of the growth medium during sampling, incubation or analysis processes. The device of the current invention also allow for the rotation of the upper part (A) discs to open, semi-open or closed positions of the intake holes/nozzles/slits as well as the rotation of the whole upper part (A) over the lower part (B) to allow for the change of impaction locations on the growth medium surface, thus avoids stacking of colonies of collected microorganisms on impaction point of the growth/culture medium surface avoids damage of medium surface during extended sampling durations. The invention simplify the manufacturing of growth medium plates used for active air sampling by introducing a plate consists of only two parts similar to traditional petri dishes and avoids traditional assembly of a petri dish filled with growth/culture medium inside disposable or reusable atriums, impactors or sampling heads. The invention also simplify the automation of viable active air sampling by reducing steps to be conducted by the automation/robotic system.

Description

Device for viable/microbiological active air sampling with no removed lid (rotation discs lid) and its manufacturing method

Microbial/viable measurement/monitoring of air/environmental air quality.

One method for measuring the microbial quality of air/environmental air, a specific volume of air is sampled by a device (air sampler) that direct the withdrawn air to a petri dish containing microbiological culture medium.

The medium plate will be later incubated in order to allow for the growth of collected microorganisms to a detectable level. According to the number of collected CFUs (colony forming units) of microorganisms, air quality could be determined and/or classified according to predefined criteria as per national and international regulatory codes and guidelines.

To perform the sampling, The petri dish containing microbiological culture medium is placed inside either:

The Air sampler device and covered with perforated stainless steel head or
inside stainless steel Atrium/Plate with perforated head that is connected remotely to the Air sampler device via a hose or
Inside Disposable, plastic Atrium with perforated head covered with plastic lid that is connected remotely to the Air sampler device via a hose.

Air will pass through perforations and come in contact with the culture medium inside the petri dish by air withdrawal forces (vacuum) exerted by the device.

The invention represents a plate with rotating discs representing the lid that avoids the removal of the lid (as in conventional methods) to start sampling.

The plate consists of two parts :
Part A: The lid , which is composed of two rotating transparent plastic circular discs (e.g. polystyrene) fit to each other with a nut or any other mean. Both discs are perforated with exact number of holes/nozzles/slits (e.g. 310 holes-other models could be configured) of specific hole/nozzle/slit diameter (e.g. of 0.5 or 0.6 mm-other models could be configured). The upper disc rotates over the lower disc to allow for different positions:
* Open position : in which holes/nozzles/slits of the upper disc are typically above holes/nozzles/slits of lower disc to allow for an open passage for air towards part B of the plate.
* Closed position : in which holes/nozzles/slits of upper disc are typically above solid non-perforated area of lower disc and holes/nozzles/slits of lower disc are typically below solid non-perforated area of upper disc to prevent passage of air towards inside of the plate.
* Semi-Open positions : in which some of the holes/nozzles/slits of the upper disc (e.g. 240 or 80 holes/nozzles/slits -other models could be configured) are typically above some holes/nozzles/slits of the lower disc (default of 240 or 80 holes/nozzles/slits -other models could be configured) to allow an open passage of air towards inside of the plate, while other holes/nozzles/slits of both discs face solid non-perforated parts. Semi-open positions give an optional control over the so-called "collection efficiency" of the device as well as control over the sampling duration and to avoid colonies stacking and/or agar damage (cracks) due to prolonged sampling duration.
Part B: The Base which is composed of one molded transparent plastic (e.g. polystyrene) circular plate of two compartments and a connector:
1- The inside compartment of typical diameter of standard petri dishes (e.g. 90 mm -other models could be configured). The inside compartment of the plate (base) to be filled with microbiological culture/growth medium. The upper edges of the inside compartment have certain cuts that allow air passage to the outer compartment.
2- The outer compartment of typical diameter (e.g. 100 mm -other models could be configured) allows the air passage to the connector.
3- The connector designed for pneumatic connection with the sampling device/pump (vacuum source). The connector designed to be a male (nipple) part fits to a female socket connected to the air sampler device via a hose or any means of interlocking and/or connection systems. The tip of the connector maybe covered by a plastic cap or any other suitable parts. Part B could be configured to fit for devices that it would be placed inside to control the duration and monitoring of the sampling process.

Part A (the lid) fits as a screw thread cap to Part B (the base) to avoid any leaks between the two parts and to allow for changing the sampling positions by rotation of the whole lid (Part A) over Part B (the base). Part A could also be fitted to part B with any means of interlocking and/or sealing systems.

The inside compartment of plate base part B (Part B) is filled with a specific volume of the microbiology culture/growth medium, followed by fitting Part A (the lid in closed position) to Part B. The closed filled plate is sterilized by a suitable sterilization method (e.g. gamma radiation) then delivered to sampling location.

During sampling, the connector is connected to the sampler device followed by rotation of the lid upper disc to "open" or a "semi-Open" position to allow the passage of the withdrawn air through the intake holes/nozzles/slits. The sampler device is turned on for a specific duration or specific volume of air.

The screw fitting Part A (the lid) allows for a slight rotation of the whole part A over Part B (the base) to change the locations where withdrawn air hits/impacts over the culture medium surface to avoid colonies stacking and/or agar damage (cracks) due to prolonged sampling duration.

After completion of sampling, the rotation of the lid upper disc allows the lid intake holes/nozzles/slits to come to "close" position to close the plate and send it for incubation.

After incubation, colonies of microorganisms-if present- to be counted and hence the microbial quality of environmental air to be determined.

1- Complex Intervention/procedure required for active sampling:
To conduct conventional microbiological active air sampling, one should sterilize the device head e.g. by autoclaving, remove the lid of petri dish containing growth/culture medium, place the petri dish inside the device, fit the pre-sterilized head of the device over the plate that was placed inside the device and start the device for sampling. After sampling, one should remove the device head, remove the petri dish from the device, cover the petri dish again with its cover/lid and send the petri dish to incubator. To conduct more than one sample, the head of the device will require to be sterilized or disinfected between every sample.

2- Removal of plate lid in conventional method:
The lid of the petri dish must be removed before conducting the sampling and should be placed again after completion of sampling. This includes risk of potential contamination (false positive results) during the removal and re-covering of the petri dish by the lid. The removed lid also require additional space besides the sampling location which is not always available, also the lid maybe contaminated from this space at which it is placed either in upside or in downside positions. This contamination maybe transferred later to the growth/culture medium inside the petri dish after placing the contaminated cover over the plate to close it.

3- colonies stacking and/or agar damage (cracks) due to prolonged sampling duration:
The fixed head position may result in colonies stacking and/or agar damage (cracks) especially with prolonged sampling duration as the air is coming to contact the same exact location on the surface of the microbiological medium during the whole duration of sampling.

4- High cost and complex manufacturing method of disposable heads/atriums/Plates:
Market available disposable configurations are composed of petri dish placed inside disposable atrium/heads/Plates. This increases the cost, as two parts are required: a petri dish containing the medium and the disposable atrium/head. The manufacturing process will also be complex, as petri dish must be filled separately with medium followed by a next step of assembly of the filled petri dish inside the disposable atrium/head.

5- Complex procedure for automation of the sampling process: as described above, the steps required for conducting of sampling are too much and accordingly the automation steps.

The invention represents a solution that integrates the removed lid with perforated head (Part A: rotating discs lid) and integrates the petri dish base with the body of the disposable atrium/head (Part B: base of two compartments and a connector) which will avoid:
1- Complex intervention/method required for sampling
2- Potential contamination risk coming from removing and re-placing the lid of conventional method
3- Semi-open positions and rotation of the whole lid (Part A) avoid stacking of colonies and/or agar damage (cracks) especially with prolonged sampling duration.
4- Lower the cost as it is presented as final two parts (Part A + Part B) and avoid extra steps required during assembly and manufacturing of the disposable unit.
5- Simplification of steps required for automation of active sampling process. Connecting the plate connector to the vacuum source and rotation of the upper disc of the lid (Part A) will be the only required steps to start the sampling.

a perspective view of a plate of the present invention
a top view of a plate of the present invention
assembly a plate of the present invention showing parts
a perspective view of the upper disc of the lid Part A of the plate of the present invention
a perspective view of the lower disc of the lid Part A of the plate of the present invention
a perspective view of The Base Part B of the plate of the present invention
a top view of a plate of the present invention at open position
a top view of a plate of the present invention at closed position
a top view of a plate of the present invention at semi-open position 1
a top view of a plate of the present invention at semi-open position 2
Rotation of lid Part A of the plate of the present invention to allow contact with a new area within culture medium

Description of Embodiments and Examples

In an embodiment, for example, the plate of the current invention provides a method of sampling the air and/or gases containing microorganisms/biological particles using the plate for a single use only, and optionally disposing of the plate after use. In an embodiment, for example, the plate of the current invention provides a method of monitoring microorganisms/ biological particles in cleanroom or environments where the microbiological air quality is of concern such as aseptic environments.
In an embodiment, for example, the plate of the current invention provides a method to conduct conventional microbiological active air sampling, without removing the lid of petri dish containing microbiological culture medium. In an embodiment, for example, the invention eliminates placing the petri dish inside the device and eliminates fitting the pre-sterilized head of the device over the plate in conventional devices. In an embodiment, for example, the invention eliminates covering the petri dish again with its cover after sampling and thus eliminates the risk of false contamination.
In an embodiment, for example, the plate's lid part A and the plate's Base part B each independently comprise a molded structure. The plate's lid part A, the plate's Base part B or both are optically transparent to allow visualization, optical detection or imaging of particles in the growth medium without physically accessing the growth medium. The plate's lid part A and the plate's Base part B each independently comprise a polymer material, such as a synthetic or natural polymer. The plate's lid part A and the plate's Base part B each independently comprise a material that could be sterilized. The plate of the current invention provides a method for sterilizing the plate in a fully assembled configuration wherein the impact surface remains enclosed by the closed position of the plate's lid part A that eliminates the need for a user to physically access the impact surface after sterilization or for contacting the growth medium after particles collection.
In an embodiment, for example, the plate of the present invention may include a range of additional structural features to facilitate effective use and avoidance of contamination. The plate base part B has grooves allow for effective stacking of set of plates, thereby minimizing the potential damage or contamination during transfer to and from a sampler.
In an embodiment, for example, the plate lid part A fits to the plate Base part B to entirely contain the impact surface that comprises a growth medium of different types such as agar, broth, and other substrates to receive microorganism/ biological particles in the airflow by providing an airtight seal around the impact surface, thus only allowing air to pass through the intake holes/nozzles/slits and interact with the impact surface. The plate's lid part A and the plate's Base part B engage via a substantially airtight seal via a selectively screw thread connection or via an O-ring gasket/connection, for example, provided between a bottom surface of the plate's lid part A and a top surface of the plate's Base part B or by any other interlocking system.
In an embodiment, for example the plate's lid part A upper disc rotates to allow the intake holes/nozzles/slits come exactly over the all holes/nozzles/slits of the lower disc in (open position), thereby allowing the airflow containing particles to impact on the surface of the growth medium.
In an embodiment, for example the plate's lid part A upper disc rotates to allow the intake holes/nozzles/slits come exactly over the some holes/nozzles/slits of the lower disc in (semi-open position) while the rest of the holes/nozzles/slits will come exactly over the solid part of the lower disc, thereby allowing the airflow containing particles to impact on the surface of the growth medium via some of the holes/nozzles/slits only and not vial all holes/nozzles/slits of the upper disc.
In an embodiment, for example the plate's lid part A upper disc rotates to allow the intake holes/nozzles/slits come exactly over the solid part of the lower disc in (Closed position), thereby maintaining a sterile environment for the growth medium prior to sampling the airflow containing microorganisms/ biological particles or for providing a tightly sealed environment for the growth medium before sampling the airflow and preventing contamination of the growth medium after sampling the airflow.
In an embodiment, for example the plate provides a method for sampling microorganisms/ biological particles from a fluid flow by allowing the connector of the plate Base part B base to be connected to the sampling device or pump, followed by allowing the plate's lid part A positioned to open or semi-open position allowing to receive at least a portion of the biological particles in the fluid flow. The plate's lid part A provides a flow of the sampled fluid through both upper and lower discs holes/nozzles/slits. The step of detecting viable microorganisms/ biological particles received by the impact surface comprising optically characterizing at least a portion of the particles without removing the lid by visualizing, optically detecting or imaging the particles. The growing step comprises allowing the biological particles comprising microorganisms to grow until being visible by eye or detectable using an optical detector or imaging device.
In an embodiment, for example The intake holes/nozzles/slits of the plate's lid part A upper and lower discs comprise holes/ nozzles/slits provided in a preselected pattern. The plate's lid part A, the plate's Base part B engage so as to provide the impact surface at a preselected distance from the intake holes/nozzles/slits of the plate's lid part A allow for collection of at least 50% of the particles having a specific cross sectional dimensions according to the so called collection efficiency. The collection efficiency could vary according to the number of holes/nozzles/slits in both discs of the plate's lid part A, the selected position (open or semi-open), fluid flow rate and the distance between the holes/nozzles/slits and the surface of the medium inside the plate's Base part B inside compartment.
In an embodiment, for example The plate said part A the lid rotates or move up/down over said plate base part B to allow for change and control the said distance between said part A the lid rotates or move up/down over said plate base part B to control for the said physical efficiency of the air sampling process.
In an embodiment, for example, the plate's lid part A may have an adapter that connects it to the compressed air/gases sources in case of compressed air/gases sampling.
In an embodiment, for example, the invention eliminates the need for a space at which the removed lid in conventional methods placed either in upside or in downside positions. In an embodiment, for example, the invention eliminates the contamination that maybe transferred later to the medium inside the petri dish after placing the contaminated cover/lid over the plate to close it.
In an embodiment, for example, the invention provides a method to avoid colonies stacking and/or agar damage (cracks) due to prolonged sampling duration. In an embodiment, for example, the invention provides a method for controlling the number of open holes/nozzles/slits of the plates' lid part A. In an embodiment, for example, the invention provides a method for changing the location of fluid impaction on the medium culture surface.
In an embodiment, for example, the invention provides a method for eliminating the high cost and complex manufacturing and assembly method of disposable heads/atriums. In an embodiment, for example, the invention provides disposable two parts preassembled that could be filled with the medium culture and closed directly. In an embodiment, for example, the invention eliminates further processing of filled culture medium required for assembly steps with the plastic atriums/heads.
In an embodiment, for example, the invention provides a way for automation of active air sampling process. In an embodiment, for example, the invention provides reduction of steps required for automation to two steps only: connecting the device to sampling hose of vacuum source and rotation of upper disc of the plate's lid part A to open, semi-open or closed positions.

Monitoring the microbiological and/or viable air/gases quality in areas, environments, spaces, rooms, cleanrooms, facilities, lines and/or any other air source where air microbiological quality of concern.

PTL1:

NPL1:

Claims

A device designed as a plate comprising of two parts:
Part A: The lid, which is composed of two rotating transparent plastic circular discs (e.g. polystyrene) fit to each other with a nut or any other mean both discs are perforated with exact number of holes/nozzles/slits of specific hole/nozzle/slit diameter. The upper disc rotates over the lower disc to allow for different positions: open, semi-open and closed positions.
Part B: The Base, which is composed, of one molded transparent plastic (e.g. polystyrene) circular plate of two compartments and a connector:
The inside compartment of typical diameter of standard petri dishes (e.g. 90 mm -other models could be configured). The inside compartment of the plate (base) to be filled with microbiological culture medium. The upper edges of the inside compartment have certain cuts that allow air passage to the outer compartment.
The outer compartment of typical diameter (e.g. 100 mm -other models could be configured) allows the air passage to the connector.
The connector designed for pneumatic connection with the sampling device (vacuum source). The connector designed to be a male (nipple) part fits to a female socket connected to the air sampler device via a hose or any means of interlocking and/or connection systems. The tip of the connector maybe covered by a plastic cap or any other suitable parts.
Part B could be configured to fit for devices that it would be placed inside to control the duration and monitoring of the sampling process.
Part A (the lid) fits as a screw thread cap to Part B (the base) to avoid any leaks between the two parts and to allow for changing the sampling positions by rotation of the lid (Part A). Part A could also be fitted to part B with any means of interlocking and/or sealing systems.
The inside compartment of plate base (Part B) is filled with a specific volume of the microbiology culture medium, followed by screw fitting Part A (the lid in closed position) to Part B. The closed filled plate is sterilized by a suitable sterilization method (e.g. gamma radiation) then delivered to sampling location.
The plate of claim 1, 2 or 3 comprising a connector to allow the connection between the plate and a sampling device, pump or vacuum source by a pneumatic connection, clamp, hose-barb or any other system that allows for easy connect/disconnect the plate from the device and avoid air leakage during sampling.
The plate of claim 1, 2 or 3, wherein said plate lid part A provides a substantially flow of said fluid through said plate base part B followed by flow of the said fluid via the connector to the sampling device/vacuum source for providing said fluid flow through said plate, wherein said flow changes direction after passing through said intake apertures.
The plate of claim 1, 2 or 3, wherein said plate base part B part B, the lid part A each independently comprise a molded structure.
The plate of claim 1, 2 or 3, wherein said part A the lid and said plate base part B each independently comprise a polymer material.
The plate of claim 1, 2 or 3, wherein said plate base part B has grooves provided on an outer surface to allow for effective handling of the plate by a user to allow for effective stacking of a plurality of said plates.
The plate of claim 1, 2 or 3 comprising a single-use device or a disposable device.
The plate of claim 1, 2 or 3, wherein said part A the lid and said plate base part B each independently comprise a sterile material.
The plate of claim 1, 2 or 3, wherein said intake apertures of said part A the lid comprise two discs of a plurality of nozzles/ slits or holes provided in a preselected pattern.
The plate of claim 1, 2 or 3 further comprising a rotating lid that avoids the removal of the cover provided traditional plates/devices for covering said intake apertures, thereby maintaining a sterile environment for said growth medium prior to and after sampling said fluid flow containing particles or for providing a sealed environment for said growth medium after sampling said fluid flow containing particles and avoids false positive contamination during and after sampling.
The plate of claim 1, 2 or 3, wherein said part A the lid and said plate base part B engage via screw thread or an O-ring connection or eclipse closure or compression interlocking system to provide: a substantially airtight seal, selectively removable interlocking connection and allowable rotation of the whole Part A over Part B the base while maintaining the plate closure system integrity to allow for changing the location of said sampled air impaction with said growth medium inside said part B the base.
The plate of claim 1, 2 or 3, wherein said Part A the lid and Part B the base engage to entirely contain said impact surface.
The plate of claim 1, 2 or 3 further comprising a rotating lid that provides different positions: open, semi-open or closed positions for the said intake apertures of said part A the lid plurality of nozzles/ slits or holes while maintaining a sterile environment for said growth medium prior to and after sampling said fluid flow containing particles or for providing a sealed environment for said growth medium after sampling said fluid flow containing particles and avoids false positive contamination during and after sampling.
The plate of claim 1, 2 or 3, wherein the distance between said part A the lid and said plate base part B is configured for the said predetermined physical efficiency of the air sampling process.
The plate of claim 1, 2 or 3, wherein said part A the lid rotates or move up/down over said plate base part B to allow for change and control the said distance between said part A the lid and said plate base part B to control for the said physical efficiency of the air sampling process.
The plate of claim 1, 2 or 3 for monitoring the biological, microbiological and/or viable particles of air and or gases quality in areas, spaces, rooms, cleanrooms, facilities, lines and/or any other air source where air microbiological quality of concern.
The plate of claim 1, 2 or 3, the plate's lid part A may have an adapter that connects it to the compressed air/gases sources in case of compressed air/gases sampling.
The plate of claim 1, 2 or 3, wherein the plate Part B base further comprises a growth medium in inside compartment positioned to receive said particles in said fluid flow, wherein said impact surface is a receiving surface of said growth medium wherein said growth medium comprises an agar plate or any other culture medium.
The plate of claim 1, 2 or 3, reduces the steps required for manual and/or automatic/robotic sampling to only two steps: connection with the sampling source via the connector and rotation of the upper disc of part (A) to one of the sampling positions.
The plate of claim 1, 2 or 3, wherein said plate base part B, the lid part A or both are optically transparent so as to allow visualization, optical detection or imaging of particles in said growth medium without physically accessing said growth medium so as to allow determination of the amount of viable microbiological/biological particles on said impact surface and to allow determination of the genus or species of viable biological particles on said impact surface without disengaging said part A the lid and said plate base part B.
A method for sampling biological particles from a fluid flow, said method comprising the steps of: sampling said fluid flow with a plate; said plate comprising: a part A the lid comprising one or more intake apertures for sampling said fluid flow containing said biological particles; an plate base part B connected to receive at least a portion of said fluid flow from said part A the lid; said plate base part B comprising an impact surface positioned to receive at least a portion of said biological particles in said fluid flow and an outlet for exhausting said fluid flow, wherein said part A the lid and said plate base part B are integrated components that engage to enclose said impact surface; and growing at least a portion of said biological particles received by said impact surface; wherein said growing step is carried out without disengaging said part A the lid and said plate base part B.
The method of claim 23, comprising monitoring microbiological/biological particles in cleanrooms or environments or in air or one or more process gases.
A method for sterilizing said plate in a fully assembled configuration wherein said impact surface remains enclosed by said part A the lid and plate base part B during sterilization; sampling said fluid flow with said plate,
The method of claim 23, wherein at least a portion of said plate base part B, part A the lid or both are optically transparent, said method further comprising optically characterizing at least a portion of said particles without disengaging said part A the lid and said plate base part B is by visualizing, optically detecting or imaging said particles.
The method of claim 23, comprising sampling said fluid containing said particles using said plate for a single use only.
The method of claim 23, wherein said plate base part B further comprises a growth medium positioned to receive said particles in said fluid flow, wherein said impact surface is a receiving surface of said growth medium.
The method of claim 23, wherein said method does not include a user physically contacting said growth medium after it has been contacted with said particles.
The method of claim 23, further comprising the step of providing a rotation discs of said part A the lid for covering said intake apertures, thereby sealing said growth medium after said sampling step.
A method for making a plate, said method comprising the steps of: molding the discs of part A the lid comprising one or more intake apertures independently having lateral and thickness dimensions; assembly of both discs of part A the lid with a nut or any other assembly meanings, molding a plate base part B comprising a growth medium reservoir and an outlet connector, wherein said part A the lid and plate base part B are designed to engage to enclose said growth medium reservoir; and optically inspecting said molded part A the lid discs to verify at least one physical dimension of said intake apertures is within one or more preselected tolerance ranges.
The method of claim 31, wherein said intake apertures are holes, nozzles or slits.
The method of claim 31, wherein said step of optically inspecting said molded both parts A and B is carried out using a manual, semi-automatic or automated inspection system.
The method of claim 31, wherein said step of filling the reservoir (inside compartment) of part B the base with growth medium suitable for the growth of sampled biological particles.
The method of claim 31 further comprising providing an O-ring, screw thread, eclipse closure or any interlocking system on said part A the lid or said plate base part B to allow for forming a seal between said part A the lid and said plate base part B.
The method of claim 31 further comprising sterilizing said part A the lid and plate base part B filled with growth medium.