WO2013053011A1

WO2013053011A1 - Storage cassette

Info

Publication number: WO2013053011A1
Application number: PCT/AU2012/001236
Authority: WO
Inventors: Jason Chaffey; Haidong ZHENG
Original assignee: Bluechiip Limited
Priority date: 2011-10-12
Filing date: 2012-10-12
Publication date: 2013-04-18

Abstract

A storage cassette including a casing having a substantially hollow body to receive at least one sample, each sample being physically associated with a machine readable tag; wherein the machine readable tag is readable by an interrogator positioned outside of the storage cassette.

Description

STORAGE CASSETTE

Field of the Invention

This invention relates to the storage and monitoring of samples in a temperature-controlled storage environment, such as the cold storage of biological samples in cryogenic tanks. Background of the Invention

Biological samples are collected and stored in many different types of facilities, for a great variety of applications. Such applications include the storage of samples collected during clinical trials in pharmaceutical companies, research samples used in university laboratories, samples archived in hospitals, samples used in the discovery of biological markers for diagnostic testing, forensic samples from crime or disaster scenes and so on. Cord blood and stem cell samples are one example of a biological sample required to be stored in the very low temperatures provided by liquid nitrogen. In order to ensure sample integrity, both samples are required to be typically maintained at temperatures of less than minus 150^QC.

Typically, in each of the systems for storing biological samples, each of a large number of samples is stored in its own small plastic bag, tube or other container. The small plastic bag, tube or other container is stored in a cassette which in turn is held in a rack. The rack holding a plurality of cassettes which each hold one or more samples is then placed in the temperature controlled storage environment such as a cryogenic tank for example. Each tank typically stores a plurality of racks and accordingly stores many biological samples.

Tracking of the samples is done by reading hand written labels or barcodes on the bags or containers. In order to identify a particular sample stored within a cassette, it is necessary to firstly remove the rack holding the relevant cassette from the tank, secondly to remove the cassette from the rack and thirdly to open the cassette to identify the samples or samples stored therein. This process involves removing each and every sample stored within a particular rack from the temperature controlled environment and exposing the sample to the ambient temperature.

Such cassettes are ordinarily formed from aluminium and are based on a bilateral arrangement wherein the two sides are releasably locked together by a lever arrangement. The lever is moved to the locking position holding the two sides together to facilitate deposition of the cassette into the rack. The lever is removed from its locking position to open the cassette to facilitate identification of the sample stored therein.

It would be desirable to provide a system for storing and monitoring samples which enables improved operating practices to be followed from those described above. It would also be desirable to provide a system for storing and monitoring samples which ameliorates and/or overcomes one or more problems or inconveniences of the prior art.

The above discussion of background art is included to explain the context of the present invention. It is not to be taken as an admission that any of the documents or other material referred to was published, known or part of the common general knowledge at the priority date of any one of the claims of this specification. Summary of the Invention

According to an aspect of the present invention, there is provided a storage cassette including:

a casing having a substantially hollow body to receive at least one sample, each sample being physically associated with a machine readable tag;

wherein the machine readable tag is readable by an interrogator positioned outside of the storage cassette.

At least a portion of the machine readable tag may be exposed to a region outside of the storage cassette.

Preferably, at least a portion of the machine readable tag protrudes through an aperture in the casing of the storage cassette.

According to one embodiment, each sample is held in a sample storage bag and the machine readable tag is attached to a port projecting from the sample storage bag. An interior of the storage cassette may be configured to receive the one or more sample storage bags.

The casing may include an insulation barrier to insulate the samples stored within the storage cassette from an ambient temperature. The insulation barrier may comprise a sealed air gap. Alternately, the insulation barrier comprises a material having low thermal conductivity.

In one form of the invention, the machine readable tag includes a plurality of resonant members encoding an identification code.

According to another aspect of the present invention, there is provided a storage cassette including:

a casing having a substantially hollow body to receive a sample held in a container;

a machine readable tag attached to the container such that at least a portion of the machine readable tag protrudes through an aperture in the casing of the storage cassette;

wherein at least a portion of the machine readable tag is exposed to a region outside of the storage cassette to facilitate reading by an interrogator positioned outside of the storage cassette.

According to yet another aspect of the present invention, there is provided a method for storing samples in a temperature controlled storage environment, the method including the following steps:

(a) containing a sample in a container, the sample being physically associated with a first machine readable tag, the first machine readable tag being readable from a tag reader positioned outside of the storage cassette;

(b) placing the container in a storage cassette including a casing having a substantially hollow body for receiving the container;

(c) placing the storage cassette in a temperature controlled storage environment, the temperature controlled storage environment being associated with a second machine readable tag;

wherein the tag reader is used to read the first and second machine readable tags to facilitate recordal of the sample location in a database.

At least a portion of the first machine readable tag may be exposed to a region outside of the storage cassette. Preferably, at least a portion of the first machine readable tag protrudes through an aperture in the casing of the storage cassette.

According to an embodiment, step (c) is preceded by the step of placing the storage cassette in a rack, the rack being associated with a third machine readable tag.

The method may further include the step of retrieving the sample from the temperature controlled storage environment.

According to one particular form of the invention, the step of retrieving the sample from the temperature controlled storage environment includes the following steps:

retrieving the sample location from the database;

using the tag reader to read the second machine readable tag to identify the temperature controlled storage environment in which the sample is held;

using the tag reader to read the third machine readable tag to identify the rack in which the sample is held;

partially removing the rack from the temperature controlled storage environment;

using the tag reader to read the first machine readable tag to identify the storage cassette holding the sample;

removing the storage cassette holding the sample from the rack; and returning the rack to the temperature controlled storage environment.

The method may further include the step of using the tag reader to read the third machine readable tag associated with the sample for sample identification before sample processing or use.

Brief Description of the Drawings

Embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings. It is to be understood that the particularity of the drawings and embodiments does not supersede the generality of the preceding description of the invention.

In the drawings:

Figure 1 is a perspective view of a storage cassette according to an embodiment of the present invention. Figure 2 is a perspective view of the storage cassette of Figure 1 with a sample storage bag situated therein.

Figure 3 is a schematic representation of a machine readable tag.

Figure 4 is a schematic representation of an interrogator.

Figure 5 shows a close up view of the machine readable tag according to an embodiment of the present invention.

Figure 6 shows a cross section through the storage cassette of Figure 2.

Figure 7 is a schematic drawing showing the step of tagging the sample bags and storage cassettes.

Figure 8 is a schematic drawing showing the step of loading the sample bag into the cassette

Figure 9 is a schematic drawing showing the step of opening the temperature controlled storage tank and rotating the tank to the partition wherein the rack is to be located.

Figure 10 is a schematic drawing showing the step of loading the cassette into the rack.

Figure 1 1 is a schematic diagram showing the step of using the interrogator to record the cassette, rack and tank identifiers to record the location of the sample.

Figure 12 is a schematic drawing showing the step of placing the loaded rack into the temperature controlled storage tank.

Figure 13 is a schematic drawing showing the step of closing the temperature controlled storage tank.

Figure 14 is a schematic drawing showing the step of retrieving the sample location from the database.

Figure 15 is a schematic drawing showing the step of opening the temperature controlled storage tank and rotating the tank to the partition wherein the sample to be retrieved is located.

Figure 16 is a schematic diagram showing the step of using the interrogator to identify the rack where the sample to be retrieved is located.

Figure 17 is a schematic diagram showing the step of partially removing the rack from the temperature controlled storage tank to identify the cassette casing the sample to be retrieved. Figure 18 is a schematic diagram showing the step of removing cassette casing the sample from the rack and restoring the rack in the temperature controlled storage tank.

Figure 19 is a schematic diagram showing the step of the cassette being transferred to a transport module.

Figure 20 is a schematic drawing showing the step of closing the temperature controlled storage tank.

Detailed Description

Referring firstly to Figure 1 , a cassette 100 for storage of samples such as biological samples, is provided. The storage cassette 100 includes a casing 1 10 surrounding a substantially hollow body 120 configured to receive a sample (see Figure 2). The casing 1 10 comprises a bilateral arrangement having two similarly configured halves, i.e. a first side 130 and a second side 140. The first and second sides 130, 140 are preferably hinged 150 along corresponding edges 160, 170 and brought together such that their peripheral edges 180, 190 correspond to form the substantially hollow body 120 for receiving the sample.

Referring now to Figure 2, the storage cassette 100 is an intermediate storage device within which a sample 200 is enclosed before being placed in a primary storage device, i.e. usually cryogenic tank, freezer or similar temperature controlled environment. The role of the storage cassette 100 is to protect the sample 200. For example, if the sample 200 is a biological material such as blood or serum, and is stored in a typical sample storage bag 210 or other container which is formed of plastic and flexible in nature, the sample is held in a storage cassette 100 to provide rigidity and protect the sample storage bag from inadvertently being pierced or otherwise damaged which might adversely impact the integrity of the sample. In some embodiments, the storage cassette 100 may be placed in a secondary storage device, such as a rack for holding a plurality of storage cassettes before placement in the primary storage device.

For tracking purposes, the sample 200 is associated with a machine readable tag 220. The machine readable tag 220 stores data relating to the identity of the sample. The data stored on the machine readable tag 220 may for example include how, when, where and from whom the sample 200 was obtained, or alternately could simply store a unique sample identifier which is associated with a corresponding record stored in an associated database which includes how, when, where and from whom the sample was obtained.

A further machine readable tag 222 may be associated with the storage cassette 100 itself, so that in one or more embodiments the cassette itself may only be tagged or the bag may be tagged, such that the cassette can be separately, identified and its temperature monitored separately to the bag.

Referring now to Figure 3, the tag 220 could comprise any suitable machine readable tag. The machine readable tag may comprise a radio frequency identification system including an antenna and a transceiver, which reads the radio frequency and transfers the data to a processing device and a transponder, or maybe a RFID tag, which contains the RF circuitry and data to be transmitted. The antenna provides means for the integrated circuit to transmit data to the processing device which converts the radio waves received from the RFID tag into digital format which can be passed onto a computing device that can analyze the data. RFID tag could mean UHF, LF and HF types or similar.

Another example of a suitable machine readable tag 220 is a micromechanical device including a plurality of vibratable or resonant members 230 to 320 each having a particular resident frequency. A common electrical conductor 330 runs along through the vibratable members and extends beyond the vibratable members to electrical terminals 340 and 350. An antenna 360, such as a coil antenna, interconnects the terminals 340 and 350. The vibratable members 230 to 320, the electrical conductor 330, the electrical terminals 340 and 350 and the antenna 360 may be formed on a dielectrical or semiconductor substrate. An LED 370 or other light emitter may be connected across the antenna 360 in order to provide a visual indication that an excitation signal is being applied to the antenna.

The vibratable members 230 to 320 are caused to vibrate by an applied excitation or interrogation signal generated by a reader (see Figure 4) that induces an alternating current in the electrical conductor 330 by means of Faraday induction by the antenna 360. The exemplary vibratable members 230 to 320 are described in International Patent Application PCT/AU2004/000322, to the present Applicant, the entire contents of which are incorporated herein by reference. In one exemplary embodiment, the vibratable members 230 to 320 are vibratable by a Lorentz force. The Lorentz force is the force that acts on a charged particle travelling through an orthogonal magnetic field. In this instance, a magnetic field is applied to the vibratable members 230 to 320 in a direction perpendicular to the current flow through the electrical conductor 330.

Referring now to Figure 4, the machine readable tag 220 is situated to enable access by an interrogator 400 for reading information on the machine readable tag in order to transmit and record the data stored on the machine readable tag in an associated database 410. The interrogator 400 includes a manually operable reading head or wand 420 adapted to be moved by an operator to be physically proximate to the machine readable tag 220. The interrogator 400 also includes a main body 430 encasing signal processing circuitry in communication with a central controller 440. The central controller 440 includes a processor 450, a first memory device 460 for maintaining a set of instructions, such as a computer programme, for causing operation of the central controller as well as second memory device 470 for maintaining data generated during operation of the central controller. The interrogator also includes a display 480 and a data/command input device 490, such as a keyboard.

A more detailed description of the interrogator is provided in International Patent Application PCT/AU2010/001645, to the present Applicant, the entire contents of which are incorporated herein by reference.

It is to be understood that the passive tag 220 and interrogator 400 are examples only of the sort of machine readable tags and tag readers for reading the tags, that may be used in various embodiments of the present invention.

The storage cassette 100 of the present invention is particularly suited to storage of a biological sample such as blood plasma, cord blood, stem cells and other biological materials which are routinely held in bags for storage in a cryogenic tank or other temperature controlled environment. Such samples 200 are typically installed in flexible storage bags 210 which are formed from plastic or other suitable materials. The sample storage bags 210 typically include a port (not shown) for introducing biological samples into the bag. The port projects from one end of the storage bag 210 and provides a convenient location to which the machine readable tag 220 may be attached. The machine readable tag 220 includes an antenna 360 connected to a plurality of vibratable members 230 to 320 by means of conductors. The antenna 360 may be a coil antenna having a helical form. The interrogator 400 may take the form of a tube casing an interrogation coil, which also has a helical form, at its tip. The interrogation coil has a larger diameter than does the antenna 360, and the antenna is adapted to be located within the interrogation coil during tag 220 reading. In other embodiments of the invention, the interrogation coil may have a smaller diameter than that of the antenna 360, so that the interrogation coil can be inserted into the antenna during tag 220 reading. The antenna 360 and interrogation coil are concentrically located in the tag 220 reading position. In this way, inductive coupling between the interrogation coil and the antenna 360 is optimised.

Whilst it is generally convenient to use an antenna configuration with the concentric coils as described with reference to Figures 3 and 4, it is to be understood that any antenna configuration that facilitates communication between a machine readable tag and the antenna of an interrogator can be used. For example, wand, mat or other antenna configurations could be used.

The interrogator and tag and their operation are described in greater depth in International Patent Application PCT/AU2009/001293 to the present Applicant, the entire contents of which are incorporated herein by reference.

The machine readable tag 220 is physically associated with the sample storage bag 210 via attachment means. One such means is attachment of the machine readable tag 220 to a port projecting from the exterior of the sample storage bag 210. The port is a projection which exists in sample storage bags typically used for the storage of biological samples, and is therefore an existing and convenient attachment point for the machine readable tags. The machine readable tag 220 may be attached to the port by means of a sleeve which is placed around the port and is affixed thereto by any suitable means. In one embodiment the sleeve is formed of a plastic or light material which shrinks upon the application of heat so that once the sleeve is placed over the port the application of heat will serve to locally shrink the sleeve around the port and affix the machine readable tag 220 to the sample storage bag 210. Referring now to Figure 5, fixing the machine readable tag 220 to the sample storage bag 210 in such a manner causes at least a tag portion encasing the antenna 360 to project from the sample storage bag such that when the bag is placed within the storage cassette 100, at least the antenna of the machine readable tag protrudes through an aperture 500 in the storage cassette casing 1 10 and is thereby exposed to a region outside of the storage cassette 100. As a result, the machine readable tag can be read by an interrogator positioned outside of the storage cassette 510 (see Figure 2). That is, the sample storage bag 210 and the sample 200 which it contains can be identified without needing to open the storage cassette 100. This enables the sample storage bag 210 to be safely stored within the storage cassette 100 and yet allow the sample 200 to be identified without any need to open the storage cassette to physically view the sample. This can minimise or at least reduce the need to directly expose the sample 200 to the ambient temperature and light, etc which may adversely impact on the integrity of the sample.

It is to be appreciated that whilst a port is a protection which typically exists in sample storage bags used for the storage of biological samples, and is therefore an existing and convenient attachment point for machine readable tags, in other embodiments other projection may be provided on said storage bags to which the sleeve may be attached.

Moreover, the machine readable tag may comprise two or more discrete portions, e.g. a first portion including the integrated circuit, and a second portion including the antenna. In this embodiment, the first portion may be located in or on the sample storage bag, with the second portion located in the storage cassette such that when the storage bag is placed in position within the storage cassette, the first and second portions of the machine readable tag make electrical contact to form a functional machine readable tag.

In order to accommodate the sample storage bag 210 with a machine readable tag 220 attached to a port or other protrusion, the storage cassette 100 includes an aperture 500 at one end to receive a machine readable portion of the tag, i.e., the antenna 360 there through. In a particular embodiment, the casing 1 10 further includes an integrally formed recess 520 around the site of the aperture 500. The recess 520 is of sufficient depth such that a distal end of the antenna 360 defining the extent of the antenna which is protruding through the aperture 500, does not protrude beyond the peripheral extent of the storage cassette casing 1 10. This arrangement ensures that whilst the antenna 360 is exposed to a region outside of the storage cassette 510 to facilitate reading of the machine readable tag 220 by an interrogator 400 positioned outside of the storage cassette, at the same time, the antenna coil is not subject to potential breakage or other damage by knocks against an exterior of the casing of the storage cassette during handling or transport.

It is to be understood that in an alternative embodiment, the storage cassette 100 may include more than one aperture 500 at various locations around the periphery of the cassette. For example, if it were desired to store more than one sample in a storage cassette, each sample may be physically associated with its own machine readable tag which could be read via an interrogator located at a position outside of the storage cassette.

Referring back to Figure 2, the storage cassette 100 further includes fastening means 530 such as a clip or clasp to releasably secure the first and second sides 130 and 140 together, preferably at the edges directly opposing the position of the one or more hinges 150 fixing an outer edge of the first and second sides together. Thus the storage cassette 100 can be opened to place a sample containing storage bag 210 therein for example, and be releasably fastened to secure the sample therein. If the sample containing storage bag 210 is required to be removed from the storage cassette 100, the clip or clasp 530 is released to allow the first and second sides 130 and 140 to be separated along one edge, facilitating removal of the sample storage bag from the storage cassette.

Referring now to Figure 2 and 6, the interior of the storage cassette is preferably shaped, or in the case of a plastic storage cassette, may be specifically moulded to comfortably receive a typical sample storage bag 210. That is, the interior of the storage cassette may be moulded so as to provide a recessed region 540 (see Figure 1 ) within the hollow body 120 which is shaped or otherwise configured to hold a sample storage bag 210. In other embodiments, the interior of the storage cassette 100 may include other internal partitions or guides, for example in the form of various projections, for example in the form of a series of right angled projections each positioned to support a corner of a sample storage bag 210 held therein. The described recess or plurality of guides is intended to hold the sample storage bag 210 in position and prevent extraneous movement of the sample within the cassette 100.

The storage cassette 100 may further include an insulation barrier 550 to insulate the contents stored therein. The insulation of the sample 220 stored within the storage cassette 100 may be of primary importance in the case of biological samples since those types of samples may be adversely affected by changes in the ambient temperature. An insulation barrier 550 prolongs the period for which the storage cassette 1 10 can be exposed to the ambient temperature without adversely impacting the integrity of the sample 220 stored therein. An insulation barrier 550 may be provided, for example in a moulded plastic storage cassette 100 in the form of a sealed air gap or vacuum. A vacuum may effectively insulate against fluctuations in the ambient temperature. Alternatively, the insulation barrier 550 may comprise a material arranged around the internal periphery of the storage cassette. Such a material will have a low thermal conductivity, for example polystyrene, foam or a similar material. In one embodiment, the insulation barrier 550 may define a recess for receiving a typical sample storage bag as previous described.

Referring now to Figure 7, when it is desired to store a particular customer's biological sample 200 in a temperature controlled storage environment, the operator firstly applies a machine readable tag 220 to the sample storage bag 210 in accordance with the method described herein. The operator may or may not apply machine readable tag 220 to a storage cassette 100 within which the tagged sample storage bag is to be held. Referring now to Figure 8, the sample storage bag 210 is placed into the storage cassette 100, the storage cassette 100 being of the form described herein. Referring now to Figure 9, the storage cassette 100 is then placed within a temperature controlled storage environment 900 such as a cryogenic tank or similar cold storage device which will typically be associated with a further machine readable tag to facilitate identification. An interrogator 400 is used to read and capture data relating to each of the sample storage bag 210, cassette 100 and tank 900 to facilitate recordal of the sample location in an associated database 410. As described herein the machine readable tag 220 associated with the storage sample bag 210 is readable from an interrogator 400 positioned outside of the storage cassette 100.

Referring now to Figure 10, in a preferred embodiment, prior to placing the storage cassette 100 in the temperature controlled environment 900, the storage cassette 100 is placed in a rack 910, a rack holding a plurality of storage cassettes. Referring now to Figure 1 1 , the rack 910 is associated with a further machine readable tag the identity of which is also recorded in the associated database to accurately record the sample location. Referring now to Figure 12, the rack 910 holding the storage cassette 100 containing the sample 200 is then loaded into the cryogenic tank 900. Now referring to Figure 13, the operator closes the storage tank.

Referring now to Figure 14, when it is desired to retrieve a particular customer's biological sample 200 from the temperature controlled environment 900, an operator firstly retrieves the sample location from the associated database 410 generally by selecting the desired customer and searching for the desired sample. Sample location data is then retrieved from the database 410 and displayed to the operator on a graphical display 480. Referring now to Figure 15, using the sample location, the operator identifies the tank 900 in which the sample is located and opens the lid.

Referring now to Figure 16, the wand 420 forming part of the interrogator

400 is used to read the machine readable tag affixed to each of the racks 910 stored within that cryogenic tank 900 until the desired rack is located. Referring now to Figure 17, the rack 910 is partially removed from the temperature controlled storage environment 900 to enable the operator to use the interrogator 400 to read the tags 220 protruding from the various storage cassettes 100 stored within the rack. Referring now to Figure 18, when the desired storage cassette 100 is located, the storage cassette is removed from the rack 910 and the rack is returned to the temperature controlled environment 900. Referring now to Figure 19, the storage cassette 100 and its contents are then transferred to a transport module 920. Referring finally to Figure 20, the operator closes the storage tank.

The tag associated with the container storing the sample can then be read in order to identify the sample prior to processing or use of that sample. It is an advantage of the storage cassette of the present invention, that it negates the need to remove the storage cassette from the rack and open the cassette to reveal the sample storage bag held therein before being able to identify the contents of the cassette, and typically determine whether the sample stored therein is the sample of interest. When it is not possible to ascertain the identity of a sample without opening the storage cassette, it may be necessary to open many cassettes before the sample of interest is located. The results in the undesirable consequence that a number of samples which are not of interest to the operator will have been removed from the temperature controlled storage environment and exposed to the ambient temperature.

Future patent applications may be filed in Australia or overseas on the basis of or claiming priority from the present application. It is to be understood that the following provisional claims are provided by way of example only, and are not intended to limit the scope of what may be claimed in any such future application. Features may be added to or omitted from the provisional claims at a later date so as to further define or redefine the invention or inventions.

Where the terms "comprise", "comprises" "comprised" or "comprising" are used in this specification (including the claims), they are to be interpreted as specifying the presence of stated features, integers, steps or components referred to, but not preclude the presence of one or more other feature, integer, step, component or group thereof.

While the invention has been described in conjunction with a limited number of embodiments, it will be appreciated by those skilled in the art that many alternative, modifications and variations in light of the foregoing description are possible. Accordingly, the present invention is intended to embrace all such alternative, modifications and variations as may fall within the spirit and scope of the invention as disclosed.

Claims

1 . A storage cassette including:

2. A storage cassette including according to claim 1 , wherein at least a portion of the machine readable tag is exposed to a region outside of the storage cassette.

3. A storage cassette including according to claim 2, wherein at least a portion of the machine readable tag protrudes through an aperture in the casing of the storage cassette.

4. A storage cassette including according to any one of claims 1 to 3, wherein each sample is held in a sample storage bag and the machine readable tag is attached to a port projecting from the sample storage bag.

5. A storage cassette including according to claim 4, wherein an interior of the storage cassette is configured to receive the one or more sample storage bags.

6. A storage cassette including according to any one of claims 1 to 5, wherein the casing includes an insulation barrier to insulate the samples stored within the storage cassette from an ambient temperature.

7. A storage cassette including according to claim 6, wherein the insulation barrier comprises a sealed air gap.

8. A storage cassette including according to claim 6, wherein the insulation barrier comprises a material having low thermal conductivity.

9. A storage cassette including according to any one of claims 1 to 8, wherein the machine readable tag includes a plurality of resonant members encoding an identification code.

10. A storage cassette including:

1 1 . A method for storing samples in a temperature controlled storage environment, the method including the following steps:

(a) containing a sample in a customer, the sample being physically associated with a first machine readable tag, the first machine readable tag being readable from a tag reader positioned outside of the storage cassette;

(b) placing the sample storage bag in a storage cassette including a casing having a substantially hollow body for receiving the container;

wherein a tag reader is used to read the first and second machine readable tags to facilitate recordal of the sample location in a database.

12. A method for storing samples in a temperature controlled storage environment according to claim 1 1 , wherein at least a portion of the first machine readable tag is exposed to a region outside of the storage cassette.

13. A method for storing samples in a temperature controlled storage environment according to claim 12, wherein at least a portion of the first machine readable tag protrudes through an aperture in the casing of the storage cassette.

14. A method for storing samples in a temperature controlled storage environment according to any one of claims 1 1 to 13, wherein step (c) is preceded by the step of placing the storage cassette in a rack, the rack being associated with a third machine readable tag.

15. A method for storing samples in a temperature controlled storage environment according to claim 14, further including the step of retrieving the sample from the temperature controlled storage environment.

16. A method for storing samples in a temperature controlled storage environment according to claim 15, wherein the step of retrieving the sample from the temperature controlled storage environment includes the following steps:

retrieving the sample location from the database;

17. A method according to claim 16, and further including the step of:

using the tag reader to read the third machine readable tag associated with the sample for sample identification before sample processing or use. A storage cassette substantially as hereinbefore described with reference to one of the embodiments shown in the drawings.

19. A method for storing samples in a temperature controlled storage environment substantially as hereinbefore described with reference to any one of the embodiments shown in the drawings.