GB2608611A

GB2608611A - Sample collection tube

Info

Publication number: GB2608611A
Application number: GB2109702.7A
Authority: GB
Inventors: Simson David; Clarke Steven; Lloyd Carys; Hamilton Lyn; Jones Fiona
Original assignee: UK Secretary of State for Health and Social Care
Current assignee: UK Secretary of State for Health and Social Care
Priority date: 2021-07-05
Filing date: 2021-07-05
Publication date: 2023-01-11
Also published as: GB202109702D0

Abstract

A sample collection tube 10 having one or more side walls 12 and a bottom 14 that together form a chamber for containing a sample, and a base part 16 formed underneath the bottom of the chamber 13, the base part having a polygonal shape when viewed from below. The polygonal shape may be a square, octagon or hexagon and allows the tube to be locked in automated decapping equipment such that the tube will not rotate during cap removal. The base part further comprises means for uniquely identifying the tube from underneath such as a barcode or QR code. The base part may comprise a socket (fig 7; 15)which receives an insert (fig 7; 40) upon which the identifying code is present (fig 7;41). The bottom of the tube may have an inverted V shape 18 extending into the chamber. The shape maybe a conical or pyramidal shape which causes the head of a swab inserted into the tube to be diverted to one side, facilitating passage of a pipette. A screw on cap 30 is provided which engages with one or more internal threads 20 of tube. A method of collecting a sample using the tube, and a method of processing the tube is disclosed.

Description

SAMPLE COLLECTION TUBE

Field of the Invention

This invention relates to a tube with a removable cap, suitable for use in collecting biological samples for subsequent testing. The invention is particularly suitable for, but by no means limited to, containing a sample of bodily fluid and enabling the sample to be sent (in the tube) to a remote laboratory for analysis (e.g. by post, within suitable packaging). The sample may be, for example, an oral fluid (e.g. saliva or mucosal excretions, e.g. as may be collected using a nasopharyngeal swab), or blood or urine. Such collection of biological samples and subsequent laboratory-based analysis may for example be part of a nationwide "self-test" testing programme, e.g. for determining the current or past presence of the SARS-CoV-2 virus, or other such pathogens, among members of the general population. Merely by way of example, the tests in question may be polymerase chain reaction (PCR) tests.

Background to the Invention

As noted above, a sample collection tube may be used to collect a sample of bodily fluid from a person (a subject) and to send the sample to a remote laboratory for analysis. The sample may be obtained by a user of the tube in respect of themselves as the subject (as in the case of a "self-test"), or from another person (e.g. by an adult in respect of a child, or by a healthcare professional in respect of a patient, etc). As described herein, the sample may be obtained using a swab (e.g. in the case of oral fluid), although the tubes provided by the present work are in no way limited to use with swabs, and may for example be used to contain samples of blood, urine or other fluids obtained without the use of swabs. Samples that are solid rather than fluid in nature (e.g. faecal samples) may also be collected in such a tube, for subsequent analysis.

Once a user has introduced a sample (e.g. of oral fluid) into the tube, the user attaches a cap to the tube, e.g. by means of a screw thread between the cap and the tube. The tube (with the sample therein) is then sent to a remote laboratory for analysis, e.g. by post or courier, with the tube being packaged within a cardboard box, a sealed bag or a padded envelope, for example, with a view to preventing the tube from being damaged in transit, or its contents leaking and being contaminated or lost. In this regard, it will be appreciated that the cap of the tube should remain securely fastened, particularly when the tube is in transit, and should not accidentally come open, causing the contents to leak out. However, it can be difficult for the user to know how firmly to tighten the cap, and whether it has been tightened sufficiently, or too much. Insufficient tightening can result in the cap becoming undone and the contents leaking during transit, whereas overtightening can risk putting the tube and/or cap under undue stress (e.g. around the aforementioned screw thread between the tube and the cap), risking breakage of the container and leakage of the contents.

As noted above, the remote laboratory to which the tube is sent may be carrying out tests as part of a nationwide biological testing programme -for example, to determine whether the people tested currently have, or have had, a particular virus, such as SARS-CoV-2. Such a laboratory in a nationwide biological testing programme may be required to process many thousands, tens of thousands, or hundreds of thousands of sample tubes per day, in order to analyse the fluid samples therein as quickly as possible and to promptly provide test results to the respective test subjects (i.e. the people from whom the fluid samples were taken).

To expedite the removal of the cap from each tube, and the analysis process overall, the laboratory may employ automated decapping equipment, as well as other automated testing equipment such as an automated (e.g. robotic) pipetting system. In this regard, there is a desire to improve the way in which the automated decapping equipment is able to engage with each tube and the respective cap, to improve the reliability and speed of removal of the cap. In particular, as sample collection tubes are usually cylindrical in shape, they can potentially be difficult to grip and manipulate in a reliable manner by the automated decapping equipment, and consequently, due to slippage, a tube may sometimes simply be rotated by the decapping equipment, rather than being decapped.

To enable the identity of a test subject to be reliably associated with the respective sample collection tube (and the fluid sample therein), and to enable the test results to be given correctly to the respective subject, conventionally a barcode label or the like is attached to the side of the sample tube, e.g. wrapped around the tube, or affixed longitudinally along the tube. Whilst automated testing equipment may process a plurality of sample tubes simultaneously, to do this the tubes conventionally need to arranged side-by-side in a line (rather than in a two-dimensional grid array) to enable the barcodes to be scanned, which in practice restricts the number of tubes that can be processed at the same time. Moreover, even when tubes are arranged side-by-side in a line, barcode labels attached to the sides of the tubes may be obscured by adjacent tubes, making them difficult for an automated scanning system to scan. There is also a risk of the barcode accidentally peeling off the side of a tube, e.g. as the tube is manipulated by decapping equipment, which may result in the tube and the sample therein no longer being reliably associated with the respective test subject. The peeled-off label may also interfere with the operation of the automated equipment, resulting in delays to the processing of other samples.

In some tests a swab may be used to collect the biological sample. For example, a nasopharyngeal swab may be used to collect oral fluid to be tested, e.g. to detect the presence of the SARS-CoV-2 virus by means of PCR tests. For such tests, the swab itself may be inserted into the sample tube, with the absorbent head of the swab downmost, and the shaft of the swab uppermost. The tube may then be capped with the swab inside, and the tube (with swab inside) may then be sent to the laboratory for testing. At the laboratory, after the tube has been decapped (with the swab left inside), a problem can arise when using an automated (e.g. robotic) pipetting system, as a pipette of the pipetting system, upon entering the tube, may clash with the shaft of the swab. This may impede or prevent the pipette from entering the tube in the required manner, disrupting the analysis process.

There is therefore a need for a sample collection tube that addresses or at least mitigates one or more of the above problems. This is particularly significant in view of the large number of such tubes that may be sent to, and processed by, national testing laboratories on a daily basis, as any improvement in efficiency or reliability achieved in respect of a single tube results in an appreciable overall improvement in the functioning of a testing programme when scaled-up over many thousands of tubes per day.

Summary of the Invention

According to a first aspect of the present invention there is provided a sample collection tube as defined in Claim 1 of the appended claims. Other aspects of the invention are defined in the other appended independent claims. Optional features, and details of certain embodiments, are set out in the appended dependent claims.

Thus, according to a first aspect of the present invention there is provided a sample collection tube having one or more side walls and a bottom that together form a chamber for containing a sample; and a base part formed underneath the bottom of the chamber, the base part having a polygonal (e.g. square) shape when viewed in plan view from below. Advantageously, by virtue of the base part having a polygonal (e.g. square) shape, in a testing laboratory the tube can be locked in automated decapping equipment, by means of the base part engaging with said equipment, such that the tube is fixed (in a rotational sense) and will not rotate during decapping (or indeed capping) operations. This enables the automated decapping equipment to operate in a controlled, reliable and predictable manner, to remove a cap from the tube (or potentially to screw a cap onto the tube) without unwanted rotation of the tube, thus increasing the efficiency and reliability of the decapping process. Whilst a square shape of the base part works well, in other embodiments the base part may have a polygonal shape other than a square -e.g. a triangle, a rectangle, a hexagon or an octagon.

Preferably the base part incorporates means for uniquely identifying the sample collection tube from underneath. This advantageously enables multiple tubes to be scanned at the same time, from underneath, without said means being obscured by adjacent tubes. Moreover, multiple tubes can be arranged (e.g. in a rack) in a two-dimensional grid array, and scanned in such an arrangement from underneath, rather than the tubes needing to be processed individually or side-by-side in a line, thus improving efficiency and throughput in the testing laboratory.

Preferably the means for uniquely identifying the sample collection tube comprises a barcode (in particular a 2D barcode, a data matrix code or a QR code) on the underside of the base part. Such barcodes are inexpensive, can be readily attached to the underside of the tubes, and can be readily scanned using established barcode scanning technology beneath the tubes. However, other means for uniquely identifying the sample collection tube are also possible, such as a short-range RFID (radio frequency identification) tag or an NFC (near-field communication) tag, for example.

In certain embodiments the base part comprises a socket for receiving an insert, the insert providing the means for uniquely identifying the sample collection tube. Incorporating such a socket and providing such an insert is advantageous in that the insert may be manufactured, as one of many such inserts, separately from many such tubes, with each insert providing means for uniquely identifying a respective tube. The insert may then be easily fitted to the respective tube before it is sent to the end user, e.g. by push-fitting the insert into the socket of the tube.

Thus, the sample collection tube may further comprise a said insert. The means for uniquely identifying the sample collection tube may comprise a barcode on the underside of the insert, or other identification means (e.g. an RFID or NFC tag) on or within the insert.

Preferably the base part has a flat underside, by means of which the sample collection tube may be stood up.

In certain embodiments the bottom of the chamber may have substantially an inverted V-shaped surface, protruding into the chamber, when viewed in side view. For instance, the bottom of the chamber may have a conical or pyramidal shape. Advantageously, when a swab is inserted in the tube (with the absorbent head of the swab downmost, and the shaft of the swab uppermost), the inverted V-shaped surface causes the head of the swab to be positioned to one side of the base, thereby facilitating the passage of a pipette (e.g. of an automated pipetting system) into the tube.

Preferably the sample collection tube has a screw-on cap.

Preferably the tube has one or more internal threads, for engaging with one or more complementary threads provided on a threaded portion of the cap. By virtue of the tube having internal threads, this prevents liquid in the tube from leaving the tube by tracking along the threads, in turn reducing the likelihood of cross-contamination of samples in the laboratory, or other issues arising from escaped fluids.

Preferably the cap incorporates a plurality of gripping ridges around the perimeter of the cap, to facilitate the process of the user screwing the cap onto the tube.

Preferably the cap incorporates means for engaging with automated decapping equipment, to enable the cap to be removed from the tube (or attached or reattached to a tube) in an automated manner, in particular in the testing laboratory, but also potentially during initial manufacture. For instance, the means for engaging may comprise a socket in the top of the cap, for receiving a complementary rotating tool of the automated decapping equipment.

In certain embodiments the top of the tube and the cap may incorporate means for interlocking with one another when the cap is fully screwed onto the tube. Such interlocking may be used to provide reassurance to the user that the cap is securely attached to the tube, the tube is unambiguously closed, and the contents are unlikely to leak during transit.

For instance, the means for interlocking may comprise one or more castellated formations around the cap, and one or more complementary formations around the top of the tube, that engage with one another as the cap becomes fully screwed onto the tube. Advantageously, such castellated formations may provide a "click" feature that gives the user a clear feel that the cap has been screwed-on sufficiently to create a sufficient seal to reliably avoid leakage, whilst also preventing the cap from being rotated further and potentially causing overtightening and/or damage.

In certain embodiments the cap incorporates a hollow internal region for forming a unified chamber with the chamber of the tube. Advantageously this increases the available height (i.e. internal height) of the chamber when the tube is closed, which in turn may beneficially enable an entire swab (including its shaft) to be accommodated within the closed tube.

According to a second aspect of the present invention there is provided a sample collection tube having one or more side walls and a bottom that together form a chamber for containing a sample; and a base part formed underneath the bottom of the chamber, wherein the base part incorporates means for uniquely identifying the sample collection tube from underneath. The advantages of such a base part are as mentioned above and described in greater detail below.

As mentioned above, the means for uniquely identifying the sample collection tube 15 may comprise a barcode on the underside of the base part.

Alternatively the base part may comprise a socket for receiving an insert, the insert providing the means for uniquely identifying the sample collection tube.

The tube may further comprise a said insert. The means for uniquely identifying the sample collection tube may comprise a barcode on the underside of the insert.

According to a third aspect of the present invention there is provided a sample collection tube having one or more side walls and a bottom; wherein the bottom has substantially an inverted V-shaped surface (e.g. conical or pyramidal in shape), protruding into the sample collection tube, when viewed in side view. The advantages of the bottom of the tube having such a shape are as mentioned above and described in greater detail below.

According to a fourth aspect of the present invention there is provided a sample collection tube having a screw-on cap, wherein the cap incorporates means for engaging with automated decapping equipment. The means for engaging may comprises a socket in the top of the cap, for receiving a complementary rotating tool of the automated decapping equipment. The top of the tube and the cap may incorporate means for interlocking with one another when the cap is fully screwed onto the tube. The cap may incorporate a hollow internal region for forming a unified chamber with the tube. The advantages of such features of the cap are as mentioned above and described in greater detail below.

According to a fifth aspect of the present invention there is provided a method of processing a sample collection tube according to any of the first, second, third or fourth aspects in a laboratory, the tube containing a sample, the method comprising: opening the tube; and analysing the sample therein.

In the event of the tube being in accordance with the first aspect, opening the tube may be performed using automated decapping equipment which engages with the base part of the tube and a cap of the tube, to open the tube in an efficient and reliable manner.

The method may further comprise identifying the tube by scanning the underneath of the base part of the tube, if the base part of the tube incorporates means for uniquely identifying the sample collection tube from underneath.

Brief Description of the Drawings

Embodiments of the invention will now be described, by way of example only, and with reference to the drawings in which: Figure 1 shows a sample collection tube and a cap thereof (detached), the sample collection tube including a base part having a polygonal (square) shape, and the bottom of the tube having an inverted V shape; Figure 2 shows the sample collection tube of Figure 1 with the cap attached; Figure 3 shows the capped sample collection tube of Figure 2, including a socket in the top of the cap, for engaging with automated decapping equipment; Figure 4 shows the underside of the base part of a sample collection tube as in Figures 1 to 3, including a 2D barcode insert, by means of which the sample collection tube may be identified from underneath in a laboratory; Figure 5 shows the underside of the 2D barcode insert of Figure 4; Figure 6 shows the underside of the base part of a sample collection tube as in Figures 1 to 3, having a socket for receiving a 2D barcode insert as in Figures 4 and 5; Figure 7 shows the 2D barcode insert of Figure 4 being introduced to the socket of the base part of the sample collection tube of Figure 6; Figures 8 and 9 are side views of a sample collection tube as in Figures 1 to 3, with Figure 9 showing the tube rotated through 90° relative to Figure 8, and Figure 10 is a longitudinal cross-sectional view along line A-A of Figure 8; Figures 11 and 12 are side views of a cap for a sample collection tube as in Figures 1 to 3, with Figure 12 showing the cap rotated through 90° relative to Figure 11, and Figure 13 is a longitudinal cross-sectional view along line A-A of Figure 11; Figures 14 and 15 are side views of a capped sample collection tube, with Figure 15 showing the tube rotated through 90° relative to Figure 14, and Figure 16 is a close-up side view of the cap of Figure 14; Figures 17 and 18 are longitudinal cross-sectional views along line A-A of Figure 14, without a swab present (Figure 17), and with a swab inside the tube (Figure 18); Figure 19 is a side view of a sample collection tube with a swab inside; and Figure 20 is a longitudinal cross-sectional view along line A-A of Figure 19.

In the figures, like elements are indicated by like reference numerals throughout.

Detailed Description of Preferred Embodiments

The present embodiments represent the best ways known to the Applicant of putting the invention into practice. However, they are not the only ways in which this can be achieved.

With reference to initially to Figures 1, 2, 3, 8, 9 and 10, the present disclosure provides a sample collection tube 10 having one or more side walls 12 and a bottom 14 that together form a chamber 13 for containing a sample. The tube 10 can be closed using a screw-on cap 30. As will be discussed in greater detail below, attachment of the cap 30 onto the tube 10 is effected by one or more threads 38 on the shank 34 of the cap 30 engaging with one or more complementary threads 20 on the inside of the tube 10. The tube 10 is particularly suitable for, but by no means limited to, containing a sample of bodily fluid and enabling the sample to be sent (in the tube 10) to a remote laboratory for analysis (e.g. by post, within suitable packaging). The sample may be, for example, an oral fluid (e.g. saliva or mucosal excretions, e.g. as may be collected using a nasopharyngeal swab -e.g. swab 50 described herein), or blood or urine. Such collection of biological samples and subsequent laboratory-based analysis may for example be part of a nationwide "self-test" testing programme, e.g. for determining the current or past presence of the SARS-CoV-2 virus, or other such pathogens, among members of the general population. Merely by way of example, the tests in question may be polymerase chain reaction (PCR) tests.

In the presently-preferred embodiments, by virtue of the tube 10 having internal threads 20, part way down the length of the tube, this prevents liquid in the tube from leaving the tube by tracking along the threads, in turn reducing the likelihood of cross-contamination of samples in the laboratory, or other issues arising from escaped fluids.

In the presently-preferred embodiments the tube 10 is made of a suitable plastics material, such as polypropylene (PP), polyethylene (PE), high density polyethylene (HDPE), polyethylene terephthalate (PET) or polystyrene (PS), e.g. by injection moulding. As those skilled in the art will appreciate, other suitable plastics materials are also possible. Preferably the tube 10 is transparent or translucent, to enable the level of a fluid sample therein to be seen through the side walls 12.

The cap 30 is also made of a suitable plastics material, again such as PP, PE, HDPE, PET or PS, e.g. by injection moulding. Possibly but not necessarily the cap 30 may be made of the same material as the tube 10. Optionally different coloured caps may be used, for example to denote different levels of priority or urgency with respect to the analysis to be performed by the laboratory.

Merely by way of example, to give an indication of scale, the tube 10 may be of the order of 90 mm to 100 mm in length, with a diameter of approximately 15 mm.

These dimensions are merely by way of example and the tube 10 may take other sizes if desired.

Optionally the side walls 12 of the tube 10 may incorporate one or more integral lines (e.g. via the moulding process) to indicate the quantity of fluid contained therein. Alternatively, an external label bearing one or more printed lines may be affixed to the side of the tube for the same purpose. In other alternatives, no indicator of fluid quantity may be provided.

Polygonal base part, to prevent rotation during automated decapping In the illustrated embodiment, the sample collection tube 10 further comprises a base part 16 formed underneath the bottom 14 of the chamber 13, the base part 16 having a polygonal shape (in this case, square) when viewed in plan view from below. In other embodiments the base part 16 may have a polygonal shape other than a square -e.g. a triangle, a rectangle, a hexagon or an octagon. By virtue of the base part 16 having a polygonal (e.g. square) shape, in the testing laboratory the tube can be locked in automated decapping equipment, by means of the base part 16 engaging with said equipment, such that the tube 10 is fixed (in a rotational sense) and will not rotate during decapping (or capping) operations. Accordingly, the cap 30 can be unscrewed by the automated decapping equipment in a controlled, reliable and predictable manner, to remove the cap 30 from the tube 10 (or potentially to screw the cap onto the tube 10) without unwanted rotation of the tube.

Merely by way of example, in the event of the tube 10 having a diameter of about mm, the sides of the square base part 16 may each be approximately 11 mm in length (i.e. the square would measure approximately 11 mm by 11 mm). It will of course be appreciated that other shapes and sizes of the base part 16 are possible.

Tube identification means (e.g. barcode), scannable from underneath Moreover, in the presently-preferred embodiments, the base part 16 incorporates means for uniquely identifying the sample collection tube 10 from underneath. In the presently-preferred embodiments, and with reference now to Figures 4 to 7, such means for uniquely identifying the tube comprises a unique barcode 41 (e.g. a 2D barcode, a data matrix code or a QR code) on the underside (i.e. downwardly facing side) of the base part 16, which may be scanned by an upwardly-facing barcode scanner incorporated in the testing laboratory's sample processing equipment.

More particularly, in the illustrated embodiment the base part 16 of the sample collection tube 10 comprises a socket 15 (see Figures 6 and 7) for receiving an insert 40, the insert 40 providing the means (in this case, 2D barcode 41) for uniquely identifying the sample collection tube 10. Such inserts 40 are advantageous in that they may be manufactured separately from the tubes 10, with each insert 40 having a unique 2D barcode 41 thereon. The inserts 40 may then be fitted to the tubes 10, e.g. by push-fitting, before they are sent to the end users.

As shown in Figure 5, with the presently-preferred inserts, the underside of the insert includes side pieces 42 separated by gaps 44, and internal pieces 46 separated by gaps 48 and defining a circular space 49 in the centre. As shown in Figure 6, the socket 15 on the underside of the base part 16 includes a formation of complementary struts 17 that grippingly engage in the gaps 44 and 48 on the underside of the insert 40, and a central hub 19 that engages within the circular space 49. It will be appreciated that, in the illustrated example, the four struts 17 are at 90° to one another, in the form of a cross, and extend outwards from the central hub 19 to meet the side walls of the base part 16. Such a configuration enables the insert 40 to be securely push-fitted or clicked into place, into the socket 15 on the underside of the base pad 16. With reference to Figure 4, once inserted into the socket 15, the insert 40 is slightly recessed relative to the side walls of the base part 16. This enables the tube 10 to be stood up by means of the side walls of the base part 16 (which themselves have a flat underside), without the insert 40 interfering with the ability to do this. Moreover, this also means that the barcode 41 itself is kept clear of the surface on which the tube 10 is stood, preventing the barcode 41 from potentially being marked by the surface and thus rendered more difficult or impossible to scan successfully.

As those skilled in the art will appreciate, in alternative embodiments other mechanisms may be used to securely grip the insert 40 in the socket 15, or to otherwise attach a barcode 41 (or other identifying means) to the underside of the base part 16, or to the underside of the sample collection tube 10 more generally.

For instance, the insert 40, bearing a unique barcode 41, may be formed instead as a flat plate and affixed to a flat surface on the underside of the base part 16, e.g. using adhesive or mechanical engagement. Alternatively, a unique barcode 41 may be printed on a sticker and affixed directly to a flat surface on the underside of the base part 16. Alternatively, a unique barcode 41 may be printed directly onto a flat surface on the underside of the base part 16, e.g. using appropriate digital printing techniques or laser etching, etc. In other alternative embodiments the base part 16 itself, or an insert 40 or the like, may incorporate other means for uniquely identifying the sample collection tube 10, such as a short-range RFID (radio frequency identification) tag or an NFC (near-

field communication) tag, for example.

However, as shown in the illustrated embodiments, a 2D barcode 41, a data matrix code or a QR code is presently preferred as the means for uniquely identifying the sample collection tube 10. Advantageously, such square barcodes can be scaled to the size of the square insert 40. This is in contrast to a 1D barcode which generally needs to be a certain size and aspect ratio.

Having the barcode 41 located on the underside of the sample collection tube 10 provides a number of advantages with respect to efficiency and logistics: Firstly, a flat barcode label 41 on the underside of the tube is easier to read (i.e. be scanned) than if wrapped around the tube.

Secondly, a flat surface (especially if recessed relative to the side walls of the base part 16) makes a barcode label 41 less prone to peeling than a 1D barcode attached to the sides of a curved tube.

Thirdly, enabling the tubes 10 to be scanned from underneath enables multiple tubes to be scanned at the same time, without any of the barcodes 41 being obscured by adjacent tubes. Moreover, the tubes 10 can be arranged (e.g. in a rack) in a two-dimensional grid array, and scanned in such an arrangement from underneath, rather than the tubes needing to be processed individually or side-by-side in a line. By processing multiple tubes in two-dimensional arrays rather than in a line enables a greater number of tubes to be processed at the same time, and ultimately for tubes to be processed more quickly by the laboratory.

As those skilled in the art will appreciate, in use the tube identification process is performed by means of a database which associates each scanned unique barcode 41 (or other identification means) with a respective user/subject, together with the results of the laboratory analysis of the respective sample, and potentially other information associated with the respective user/subject or the respective sample.

As a more general point, the base part 16 preferably has a flat underside, by means of which the sample collection tube 10 may be stood up.

Inverted V shape of the bottom of the tube Figures 8 and 9 are side views of a sample collection tube 10 as in Figures 1 to 3, and Figure 10 is a longitudinal cross-sectional view along line A-A of Figure 8. It will be noted that the tube 10 includes a collar 22 at the top (which will be described in more detail below) and that the side walls 12 incorporate internal threads 20, by means of which a cap 30 can be screwed on, and unscrewed. It will of course be appreciated that, although "side walls" 12 may be referred to, in practice the tube 10 is preferably of a generally cylindrical shape (apart from the polygonal base part 16 containing the socket 15) and thus technically has only a single side wall 12. However, the present disclosure may refer to "side walls" 12, particularly when viewing the tube 10 in longitudinal cross-section, as in such a cross-section two wall sections on opposite sides are visible.

With reference in particular to Figure 10, and as mentioned above, the side walls 12 and the bottom 14 of the tube together form a chamber 13 for containing a sample.

The bottom 14 of the chamber 13 has substantially an inverted V-shaped surface 18, protruding into the chamber 13, when viewed in side view. More particularly, in the illustrated embodiments, the bottom 14 of the chamber 13 has a conical or pyramidal shape. As shown in Figures 18 and 20, the purpose of the inverted V-shaped surface 18 is that, when a swab 50 is inserted in the tube (with the absorbent head 52 of the swab 50 downmost, and the shaft 54 of the swab 50 uppermost), the inverted V-shaped surface 18 causes the head 52 of the swab 50 to be positioned to one side of the base 14. In the testing laboratory, an automated (e.g. robotic) pipetting system may be used. Having the head 52 of the swab 50 positioned to one side of the base 14 may reduce the likelihood of a automated pipette clashing with the swab 50 (or otherwise being impeded by the swab) during testing, thus facilitating the testing process and reducing the likelihood of problems arising from undesirable swab/pipette interactions (e.g. damage or breakage of either a swab or a pipette, jamming of a pipette, etc.).

Cap design, including controlled locking mechanism Figures 11 and 12 are side views of the cap 30 for a sample collection tube 10 as in Figures 1 to 3, and Figure 13 is a longitudinal cross-sectional view along line A-A of Figure 11. The cap 30 includes a head part 32 having a user-grippable perimeter surface (which may incorporate ridges as shown, or other protrusions to aid grip), and a shank part 34 on which one or more threads 38 are formed, the threads 38 being engageable with the complementary internal threads 20 on the inside of the tube 10. In use, once the user has introduced a sample into the tube 10, the user can close the tube 10 by screwing-on the cap 30, by gripping and rotating the outer surface of the head pad 32 relative to the tube 10.

As shown in Figure 13, in the illustrated embodiment the cap 30 (specifically the shank 34) incorporates a hollow internal region 39. When the cap 30 is attached to the tube 10, the hollow internal region 39 of the cap 30 forms a unified chamber with the chamber 13 of the tube 10, as shown in Figures 17 and 18 (which are longitudinal cross-sectional views along line A-A of Figure 14). Advantageously this increases the available height of the chamber 13 when the tube 10 is closed. In turn, in the illustrated embodiment, this enables an entire swab 50 (including its shaft 54) to be accommodated within the closed tube, as shown in Figure 18.

Notably, the cap 30 includes means for engaging with automated decapping equipment in the testing laboratory, to enable such equipment to unscrew and removed the cap 30 from the tube 20. In the illustrated embodiment the means for engaging comprises a socket 36 in the top of the cap 30, for receiving a complementary rotating tool of the automated decapping equipment. The socket 36 may have a complex many-sided shape as shown in Figures 1 and 3, for example, although other shapes are also possible, as those skilled in the art will appreciate.

In practice, automated removal of the cap 30 from the tube 10 is facilitated by the synergistic combination of (a) the above-described base part 16 having a polygonal (e.g. square) shape, enabling the tube 10 to be locked in automated decapping equipment, such that it does not rotate; and (b) the socket 36 in the top of the cap 30, for receiving a complementary rotating tool of the automated decapping equipment. Similar advantages apply in the event of performing automated capping of the tube (i.e. automated fitting of the cap 30 onto the tube 10).

Preferably, the top (i.e. collar 22) of the tube 20 and the cap 30 incorporate means for interlocking with one another when the cap is fully screwed onto the tube. For example, as illustrated in Figures 11, 12, 14, 15 and 16, the means for interlocking may comprise one or more castellated formations 33 around the cap 30, and one or more complementary formations around the top (i.e. collar 22) of the tube 20. In use, as the user screws the cap 30 onto the tube 20, the castellated formations 23, 33 provide a "click" feature that gives the user a clear feel that the cap has been screwed-on sufficiently to create a sufficient seal to reliably avoid leakage, e.g. during transit (and also, in testing, to meet the 95kPa pressure test required for UN3373 compliance).

In more detail, when attaching the cap 30 to the tube 10, the cap 30 is rotated and a seal is formed between the cap 30 and the tube 10. At around the position where the seal is formed, the protruding castellation 33 on the cap 30 interferes with the near-side castellation lip on the tube 10 and an audible "click" is produced. As the cap 30 is rotated further, the protruding castellation 33 on the cap 30 interferes with the far side castellation lip on the tube 10 and is prevented from being rotated further. Accordingly, this provides improved usability as it gives the user an unambiguous "seal" position in which the cap 30 is sufficiently tightened, whilst also preventing overtightening of the cap 30.

Modifications and alternatives Detailed embodiments and some possible alternatives have been described above.

As those skilled in the art will appreciate, a number of modifications and further alternatives can be made to the above embodiments whilst still benefiting from the inventions embodied therein.

In particular, it should be noted that the features of (a) the polygonal base part 16; (b) the tube identification means (e.g. barcode 41), scannable from underneath; (c) the inverted V-shaped surface 18 at the bottom of the tube; and (d) the present cap design (including the feature of the controlled locking mechanism), may be employed in any combination, individually or together. Thus, although in the illustrated embodiments all of these features (a), (b), (c) and (d) are employed together, enabling various synergistic benefits to be achieved, in alternative implementations only feature (a) may be employed, or only feature (b), or only feature (c), or only feature (d). In other implementations, combinations of some but not all of these features (a)-(d) may be employed.

Claims

CLAIMS1. A sample collection tube having one or more side walls and a bottom that together form a chamber for containing a sample; and a base part formed underneath the bottom of the chamber, the base part having a polygonal shape when viewed in plan view from below.
2. The sample collection tube according to claim 1, wherein the base part has a square shape when viewed in plan view from below.
3. The sample collection tube according to claim 1 or claim 2, wherein the base part incorporates means for uniquely identifying the sample collection tube from underneath.
4. The sample collection tube according to claim 3, wherein the means for uniquely identifying the sample collection tube comprises a barcode on the underside of the base part.
5. The sample collection tube according to claim 1 or claim 2, wherein the base part comprises a socket for receiving an insert, the insert providing means for uniquely identifying the sample collection tube.
6. The sample collection tube according to claim 5, further comprising a said insert.
7. The sample collection tube according to claim 5 or claim 6, wherein the means for uniquely identifying the sample collection tube comprises a barcode on the underside of the insert.
8. The sample collection tube according to any preceding claim, wherein the base part has a flat underside, by means of which the sample collection tube may be stood up.
9. The sample collection tube according to any preceding claim, wherein the bottom of the chamber has substantially an inverted V-shaped surface, protruding into the chamber, when viewed in side view.
10. The sample collection tube according to claim 9, wherein the bottom of the chamber has a conical or pyramidal shape.
11. The sample collection tube according to any preceding claim, having a screw-on cap.
12. The sample collection tube according to claim 11, wherein the tube has one or more internal threads, for engaging with one or more complementary threads provided on a threaded portion of the cap.
13. The sample collection tube according to claim 11 or claim 12, wherein the cap incorporates a plurality of gripping ridges around the perimeter of the cap.
14. The sample collection tube according to any of claims 11 to 13, wherein the cap incorporates means for engaging with automated decapping equipment.
15. The sample collection tube according to claim 14, wherein the means for engaging comprises a socket in the top of the cap, for receiving a complementary rotating tool of the automated decapping equipment.
16. The sample collection tube according to any of claims 11 to 15, wherein the top of the tube and the cap incorporate means for interlocking with one another when the cap is fully screwed onto the tube.
17. The sample collection tube according to claim 16, wherein the means for interlocking comprises one or more castellated formations around the cap, and one or more complementary formations around the top of the tube.
18. The sample collection tube according to any of claims 11 to 17, wherein the cap incorporates a hollow internal region for forming a unified chamber with the chamber of the tube.
19. A sample collection tube having one or more side walls and a bottom that together form a chamber for containing a sample; and a base part formed underneath the bottom of the chamber, wherein the base part incorporates means for uniquely identifying the sample collection tube from underneath.
20. The sample collection tube according to claim 19, wherein the means for uniquely identifying the sample collection tube comprises a barcode on the underside of the base part.
21. The sample collection tube according to claim 19, wherein the base part comprises a socket for receiving an insert, the insert providing the means for uniquely identifying the sample collection tube.
22. The sample collection tube according to claim 21, further comprising a said insert.
23. The sample collection tube according to claim 22, wherein the means for uniquely identifying the sample collection tube comprises a barcode on the underside of the insert.
24. A sample collection tube having one or more side walls and a bottom; wherein the bottom has substantially an inverted V-shaped surface, protruding into the sample collection tube, when viewed in side view.
25. The sample collection tube according to claim 24, wherein the bottom has a conical or pyramidal shape.
26. A sample collection tube having a screw-on cap, wherein the cap incorporates means for engaging with automated decapping equipment.
27. The sample collection tube according to claim 26, wherein the means for engaging comprises a socket in the top of the cap, for receiving a complementary rotating tool of the automated decapping equipment.
28. The sample collection tube according to claim 26 or claim 27, wherein the top of the tube and the cap incorporate means for interlocking with one another when the cap is fully screwed onto the tube.
29. The sample collection tube according to claim 28, wherein the means for interlocking comprises one or more castellated formations around the cap, and one or more complementary formations around the top of the tube.
30. The sample collection tube according to any of claims 26 to 29, wherein the cap incorporates a hollow internal region for forming a unified chamber with the tube.
31. A method of collecting a sample using a sample collection tube according to any preceding claim.
32. A method of processing a sample collection tube according to any of claims 1 to 30 in a laboratory, the tube containing a sample, the method comprising: opening the tube; and analysing the sample therein.
33. The method according to claim 32, when the tube is as defined in any of claims 1 to 18, wherein opening the tube is performed using automated decapping equipment which engages with the base part of the tube and a cap of the tube.
34. The method according to claim 32 or claim 33, further comprising: identifying the tube by scanning the underneath of the base part of the tube, when the tube is as defined in any of claims 3 to 7 or any of claims 19 to 23.