CN212489977U

CN212489977U - Storage tube for sampling swab

Info

Publication number: CN212489977U
Application number: CN202020771191.2U
Authority: CN
Inventors: 方鹏宇; 蒋析文
Original assignee: Daan Gene Co Ltd of Sun Yat Sen University
Current assignee: Guangzhou Da'an gene Co.,Ltd.
Priority date: 2020-05-11
Filing date: 2020-05-11
Publication date: 2021-02-09
Anticipated expiration: 2030-05-11

Abstract

The utility model relates to a technical field that the sample was preserved, more specifically relates to a sampling swab is with preservation pipe, including a pipe body, be equipped with the second cavity that is used for the first cavity of storage sample release agent and is used for placing the sampling swab in the body, first cavity and second cavity intercommunication set up, the central axis of second cavity deviate in the central axis of body. When the utility model is used, the sampling swab is placed in the second cavity, and the sampling swab moves up and down and rotates to elute in the second cavity, so that the nucleic acid sample of the sampling swab is uniformly distributed in the sample releasing agent, and the sample releasing agent in the first cavity is absorbed for detection; the utility model discloses saved the process that the nucleic acid sample was drawed in the vibration elution, the swab is vertical to be placed in deviating in the second cavity that body center set up, for sample operation provides operating space, simplifies nucleic acid detection operation process, makes things convenient for clinical trial to operate.

Description

Storage tube for sampling swab

Technical Field

The utility model relates to a technical field that the sample was preserved, more specifically relates to a sampling is preservation pipe for swab.

Background

In the field of in vitro diagnosis, particularly gene diagnosis, a sample separated from a human body needs to be collected for detection, and the method for sampling by adopting a sampling swab is a simple, painless and noninvasive DNA specimen collection method. The method is suitable for collecting DNA samples of people of any age group. Swabs are commonly used as a tool for medical examination to collect microorganisms, exfoliated cells, or secretions, and the sampled swabs are stored in storage tubes for inspection. The present sampling swab preservation pipe is including dismantling body and the lid of connecting, and sealed the preserving is in the body after the sampling swab gathers patient's sample, and send into the laboratory again and draw nucleic acid and detect, but this kind of mode exists a lot of insufficiencies at present: (1) in the process of extracting nucleic acid in a laboratory, the nucleic acid sample on the swab needs to be shaken and eluted, the operation is complicated, and the infection risk caused by sample transfer is increased; (2) in the detection process, as the storage tube is not provided with a structure for fixing the sampling swab, the swab is easy to incline in the storage tube, and the detection sampling operation is influenced.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to overcome not enough among the prior art, provide a sampling is preservation pipe for swab, need not the vibration elution, and can make things convenient for subsequent detection sample.

In order to solve the technical problem, the utility model discloses a technical scheme is:

the utility model provides a storage tube for sampling swab, includes the body, be equipped with the second cavity that is used for placing sampling swab and is used for saving the first cavity of sample release agent in the body, first cavity and second cavity intercommunication setting, the central axis of second cavity deviate from in the central axis of body.

The utility model discloses a sampling is save tube for swab, sampling swab place in the second cavity, reciprocate and rotatory elution in the second cavity, sampling swab's nucleic acid sample evenly distributed can be used for detecting in the sample release agent, absorbs the sample release agent in the first cavity. The utility model discloses saved the process that the nucleic acid sample was drawed in the vibration elution, the swab is vertical to be placed in deviating in the second cavity that body center set up, for sample operation provides operating space, simplifies nucleic acid detection operation process, makes things convenient for clinical trial operation, reduces the infection risk of testing process.

Further, the central axis of the first cavity coincides with the central axis of the tube body, and the side of the second cavity is attached to the inner wall of the tube body. The first cavity is used for storing a sample releasing agent, and the position of the first cavity is defined to be beneficial to subsequent automatic detection and sampling; the position of the second cavity is limited so that the sampling swab is attached to the inner wall of the tube body, the sampling swab can stably stand in the second cavity, and adverse effects on detection and sampling caused by the inclination of the sampling swab are prevented.

Further, the top of the pipe body is provided with a first connecting part for connecting the pipe cover, and the bottom of the pipe body is provided with a fixing part. The first connecting part is used for connecting the tube cover and the tube body and sealing and storing the sampling swab and the sample releasing agent in the storage tube; the fixed part is used for the body and matches between fixed station or the fixed instrument, does benefit to the automation that realizes the tube cap rotation operation.

Furthermore, the top of the first cavity and the top of the second cavity are connected with second connecting parts, and the second connecting parts surround the outer edges of the top of the first cavity and the second cavity and the inner wall of the tube body. After the tube body is connected with the tube cover, a closed space is formed among the second connecting part, the first cavity, the second cavity, the tube body and the tube cover, and the swab and the sample releasing agent are stored in the closed space, so that the storage stability of the sample can be effectively ensured.

Furthermore, a plurality of first convex parts are arranged on the inner wall of the second cavity. On the one hand, the nucleic acid sample can be well eluted when the sampling swab is moved up and down, rotated and rotated, and on the other hand, the sampling swab is beneficial to being stably stood in the second cavity and is not easy to topple over.

Furthermore, the first convex part is a first convex rib, and the first convex rib is one or a combination of a plurality of vertical ribs, transverse ribs, inclined ribs and spiral ribs. The shape of first bead does not do the utility model discloses the restrictive regulation, other friction structures that can increase frictional force between sampling swab and the second cavity internal wall in order to improve sampling swab elution effect all can be applicable to the utility model discloses.

Further, the first convex part is a first convex point. The first salient points can be connected to form one or a combination of a plurality of vertical edge structures, transverse edge structures, oblique edge structures and spiral edge structures, and can also be processed to form irregular edge structures according to needs, so that the swab has a good elution effect when moving up and down or rotating the sampling swab, and the consumption of raw materials for preparation can be saved.

Furthermore, a plurality of second convex parts are uniformly distributed at the bottom of the inner side of the second cavity. The first convex part of the side part has an elution effect on the nucleic acid sample at the side part of the sampling swab, and the second convex part at the bottom has an elution effect on the nucleic acid sample at the bottom of the sampling swab, so that the elution effect on the sample on the sampling swab when the sampling swab moves up and down and rotates can be improved.

Furthermore, the second convex part is a second convex rib, one end of the second convex rib is arranged at the center of the bottom of the second cavity, and the other end of the second convex rib is connected with the first convex part. The position and shape of the second rib are preferably set to simplify the mold structure, simplify the molding process, beautifully design, and improve the elution effect, and are not intended as a restrictive provision of the present invention.

Further, the second convex part is a second convex point. The first salient points can be connected to form a radial edge structure which is radially distributed along the bottom of the second cavity, so that the rotary sampling swab has a good elution effect, and the consumption of raw materials for preparation can be saved.

Furthermore, the first cavity is a tapered hole, the second cavity is a cylindrical hole, and the depth of the second cavity is greater than that of the first cavity. The outer edges of one ends of the first cavity and the second cavity are connected with the second connecting portion, and the other end of the second cavity is lower than the other end of the first cavity, so that the storage stability of the sampling swab is improved.

Further, first cavity is the bell mouth, and the second cavity is cylindrical hole, first cavity overlaps with second cavity part and is formed with first side arris and second side arris, and the distance is not more than the minimum diameter of sampling swab between first side arris, the second side arris, and the sampling swab can't pass through the clearance between first side arris, the second side arris. The provision of the gap between the first side edge and the second side edge is preferable for obtaining good processability and a stable sampling swab, and is not a provision of the present invention.

Compared with the prior art, the beneficial effects of the utility model are that:

the utility model discloses a sampling is save tube for swab saves the process that the nucleic acid sample was drawed in the elution of vibration, and the swab is vertical to be placed in deviating in the second cavity that body center set up, provides operating space for sample operation, can simplify nucleic acid detection operation process, makes things convenient for clinical trial operation, reduces the infection risk of testing process.

Drawings

FIG. 1 is a perspective view of a storage tube for a sampling swab according to one embodiment;

FIG. 2 is a schematic view of a storage tube for a sampling swab according to an embodiment;

FIG. 3 is a bottom view of a storage tube for a sampling swab according to one embodiment;

FIG. 4 is a schematic view showing a structure of a first embodiment of a sampling swab storage tube with a tube cap;

FIG. 5 is a schematic view showing the structure of a storage tube for a sampling swab according to a second embodiment;

FIG. 6 is a plan view of a storage tube for a sampling swab in accordance with a second embodiment;

FIG. 7 is a perspective view of a storage tube for a sampling swab in accordance with a fourth embodiment;

FIG. 8 is a schematic view showing the structure of a storage tube for a sampling swab in the fourth embodiment;

FIG. 9 is a top view of a storage tube for a sampling swab in the fourth embodiment;

FIG. 10 is a plan view of a storage tube for a sampling swab in the seventh embodiment;

in the drawings: 1-a pipe body; 11-a first cavity; 12-a second cavity; 13-a first connection; 14-a fixed part; 15-a second connection; 16-a first projection; 17-a second projection; 2-tube cover.

Detailed Description

The present invention will be further described with reference to the following embodiments. Wherein the showings are for the purpose of illustration only and are shown by way of illustration only and not in actual form, and are not to be construed as limiting the present patent; for a better understanding of the embodiments of the present invention, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of an actual product; it will be understood by those skilled in the art that certain well-known structures in the drawings and descriptions thereof may be omitted.

The same or similar reference numerals in the drawings of the embodiments of the present invention correspond to the same or similar parts; in the description of the present invention, it should be understood that if there are the terms "upper", "lower", "left", "right", etc. indicating the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, it is only for convenience of description and simplification of the description, but it is not intended to indicate or imply that the device or element referred to must have a specific orientation, be constructed in a specific orientation, and be operated, and therefore the terms describing the positional relationship in the drawings are only for illustrative purposes and are not to be construed as limitations of the present patent, and those skilled in the art can understand the specific meanings of the terms according to specific situations.

Example one

Fig. 1 to 4 show a first embodiment of a storage tube for sampling swabs, which includes a tube body 1, a first cavity 11 for storing a sample releasing agent and a second cavity 12 for placing a sampling swab are disposed in the tube body 1, the first cavity 11 is communicated with the second cavity 12, and a central axis of the second cavity 12 deviates from a central axis of the tube body 1. The elution process of the present embodiment in which the sampling swab moves up and down and rotates in the second cavity 12 can be made as a mark attached to the outer wall of the tube 1.

When this embodiment is implemented, place in second cavity 12 after the sampling of sampling swab, reciprocate and rotatory elution in second cavity 12, the nucleic acid sample evenly distributed of sampling swab in the sample release agent, the sample release agent in absorbing first cavity 11 can be used for detecting, so just saved the process that the nucleic acid sample was drawed in the vibration elution, the swab is vertical to be placed in deviating from in the second cavity 12 that body 1 center set up, provide operating space for the sample operation, simplify nucleic acid detection operation process, make things convenient for clinical test operation, reduce the infection risk of testing process.

In order to stabilize the sampling swab in the second cavity 12, the present embodiment may slightly press the head of the sampling swab against the inner wall of the second cavity 12 by setting the size of the second cavity 12. Specifically, the second cavity 12 is sized between the sampling swab head maximum diameter and the sampling swab shaft diameter. However, it should be noted that the second cavity 12 is preferably sized to provide a good stabilization of the sampling swab and is not intended as a limiting provision of the present invention.

In this embodiment, the communication form between the first cavity 11 and the second cavity 12 may be a plurality of communication forms: the first cavity 11 is communicated with the second cavity 12 at the side part, and when the side part is communicated, a sufficient amount of sample releasing agent is added into the first cavity 11 and the second cavity 12, so that the liquid level of the sample releasing agent is higher than the lowest communication point of the first cavity 11 and the second cavity 12, and the sample releasing agent can freely flow between the first cavity 11 and the second cavity 12; the bottoms of the first cavity 11 and the second cavity 12 are communicated, and the bottom of the first cavity 11 can be arranged below the bottom of the second cavity 12 when the bottoms are communicated, so that a sample releasing agent containing a nucleic acid sample can smoothly flow into the first cavity 11 for subsequent detection and sampling. Of course, the utility model discloses the intercommunication form between first cavity 11 and the second cavity 12 is not limited to above-mentioned two kinds of forms, and other can guarantee that sample release agent flows in first cavity 11 and second cavity 12 and the elution has the sample release agent of nucleic acid sample to flow the intercommunication form of storing in first cavity 11 all to be applicable to the utility model discloses.

In order to further limit the storage position of the sampling swab in the storage tube and avoid the improper position of the sampling swab from affecting the detection sampling operation, the present embodiment further limits the distribution positions of the first cavity 11 and the second cavity 12 in the tube body 1. Specifically, the central axis of the first cavity 11 of this embodiment coincides with the central axis of the pipe body 1, and the lateral part of the second cavity 12 is pasted on the inner wall of the pipe body 1, so that the sampling instrument can conveniently stretch into the first cavity 11 to absorb the sample releasing agent, and the sampling swab is tightly attached to the inner wall of the pipe body 1 on one side in the second cavity 12, so that the sampling swab is stably erected for storage.

In the process of transporting and transferring the storage tube, the storage tube is sealed, so the top of the tube body 1 is provided with a first connecting part 13 for connecting the tube cover 2; in order to be suitable for the automatic operation of the instrument in the detection process, the fixing portion 14 is disposed at the bottom of the tube 1 in this embodiment, the structure of the fixing portion 14 may be set according to the structure of the fixed instrument or the fixed table, in this embodiment, one end of the fixing portion 14 is flush with the bottom of the tube 1, and the other end of the fixing portion 14 may extend upward to the top edges of the first cavity 11 and the second cavity 12; one side part of the second cavity 12 is tangent to the fixing part 14, and the other side is attached to the inner wall of the tube body 1. In the embodiment, the connecting part is an external thread arranged on the outer wall of the pipe body 1, the pipe body 1 is connected with the pipe cover 2 through the thread, the connection is stable, and the automatic operation can be conveniently realized; as shown in fig. 3, the fixing portion 14 is a cross structure, and when the pipe cap 2 is operated, the cross structure and the fixing table are fixed to prevent the pipe cap 2 from rotating together with the pipe body 1 when the pipe cap 2 is rotated, but it should be noted that the cross structure is preferable for having better fixing effect and better machine-shaping performance, and is not taken as the limitation of the present invention, the structure of the fixing portion 14 of the present embodiment can be designed according to the fixing table or the fixing instrument and adapted to the fixing table or the fixing instrument.

In order to reasonably distribute the positions of the first cavity 11 and the second cavity 12 in the tube 1, the second connecting portion 15 is connected to the top of the first cavity 11 and the top of the second cavity 12, and the second connecting portion 15 may be a circular truncated cone surrounding the outer edges of the first cavity 11 and the second cavity 12 and the inner wall of the tube 1, as shown in fig. 2. After the tube body 1 is connected with the tube cap 2, a closed space is formed among the second connecting part 15, the first cavity 11, the second cavity 12, the tube body 1 and the tube cap 2, as shown in fig. 4, the swab and the sample releasing agent are stored in the closed space, and the stability of sample storage can be effectively ensured. In addition, the second connecting portion 15, the first cavity 11, and the second cavity 12 of the present embodiment may be an integrally formed structure, the first cavity 11 and the second cavity 12 are partially overlapped, the cross sections of the first cavity 11 and the second cavity 12 are of a gourd-shaped structure, the first cavity 11 and the second cavity 12 are partially overlapped, and the distance between the first side edge and the second side edge formed by connecting the first cavity 11 and the second cavity 12 may be set according to the forming requirement and the shape and size of the sampling swab.

In order to endow the preservation tube with better performance, the wall thickness of the tube body 1, the wall thickness of the first cavity 11, the wall thickness of the second cavity 12, the thickness of the fixing part 14, the thickness of the second connecting part 15 and other dimensions of the preservation tube are equal, so that the cooling effect in the forming process is ensured. Of course, this is only preferred for obtaining a better performing storage tube with existing production equipment and is not intended as a limiting provision of the invention.

Example two

As shown in fig. 5 to 6, the second embodiment of the storage tube for sampling swabs of the present invention is the same as the first embodiment, except that the inner wall of the second cavity 12 is provided with a plurality of first protrusions 16, so that on one hand, the nucleic acid sample can be better eluted when the sampling swab is moved up and down, rotated and rotated, and on the other hand, the sampling swab is beneficial to stably standing in the second cavity 12 and is not easy to topple.

Specifically, the first protrusion 16 in this embodiment is a first rib, and the first rib is one or a combination of vertical edges, horizontal edges, oblique edges, and spiral edges. Of course, it should be noted that the shape of the first protruding edge listed above is not intended as a limiting rule of the present invention, and other friction structures that can increase the friction between the sampling swab and the inner wall of the second cavity 12 to improve the elution effect of the sampling swab are applicable to the present invention.

The first rib of the present embodiment may preferably be a vertical rib, but the first rib is preferably provided as a vertical rib for the convenience of demolding the pipe body 1, and is not intended as a limiting provision of the present invention.

In addition, the number of the first ribs of the present embodiment can be set to 8-12, which uniformly surround the inner wall of the second cavity 12. However, it should be noted that the number of the first ribs is not limited to the limiting specification of the present invention, and the number of the first ribs in this embodiment may be increased or decreased according to the thickness of the first ribs, the elution effect of the first ribs, and the structural parameters of the sampling swab.

EXAMPLE III

The present embodiment is a third embodiment of a storage tube for sampling swabs, and is the same as the second embodiment except that a plurality of first protrusions are disposed on the inner wall of the second cavity 12 instead of a continuous structure similar to the first ribs in the second embodiment, which can achieve better elution effect and save the amount of raw materials for preparing the tube body 1 compared to the second embodiment.

The first salient points in the embodiment can be connected to form one or a combination of a plurality of vertical edge structures, transverse edge structures, oblique edge structures and spiral edge structures, and can also be processed to form irregular edge structures according to requirements. In addition, the shape of the first salient point of the present embodiment may be a hemispherical shape, a square shape, or a friction structure that can increase the friction force between the sampling swab and the second cavity 12 when the sampling swab moves up and down or rotates.

In order to facilitate the processing of the first protrusion 16 and the demolding of the first protrusion 16, the first protrusions of the present embodiment may form a vertical rib structure uniformly surrounding the inner wall of the second cavity 12.

Example four

Fig. 7 to 9 show a fourth embodiment of a storage tube for sampling swabs according to the present invention, which is the same as the second embodiment or the third embodiment, except that: when sampling the swab, the nucleic acid sample not only adheres in the side of sampling the swab, still adheres in the bottom of sampling the swab, and this embodiment is equipped with second convex part 17 in the inboard bottom of second cavity 12 except that being equipped with first convex part 16 in the surrounding of second cavity 12 side wall, so all can play the elution effect to the nucleic acid sample of sampling the swab side and the nucleic acid sample of sampling the swab bottom. Specifically, the second protrusion 17 of the present embodiment is a second rib, one end of the second rib is disposed at the bottom center of the second cavity 12, and the other end of the second rib is connected to the first protrusion 16. When the first convex part 16 is the first convex edge and is a vertical edge, the number of the second convex edges is equal to that of the first convex edges, and the first convex edges and the second convex edges can be connected to form an integrated edge-shaped structure. It should be noted that, the structure and the number of the second bead in this embodiment are designed to be preferable for the purpose of aesthetic design and convenient processing, and are not intended to limit the present invention, and other bead structures and bead numbers that can realize the elution effect can also be applied to the present invention.

EXAMPLE five

The present embodiment is the same as the second embodiment or the third embodiment, except that the present embodiment is further provided with a second protrusion 17 at the bottom inside the second cavity 12, in addition to the first protrusion 16 surrounding the sidewall of the second cavity 12. The second protrusion 17 of this embodiment is a second protrusion, instead of the continuous structure similar to the second rib of the fourth embodiment, and this embodiment can obtain better elution effect and save the amount of raw materials for preparing the tube 1 compared to the fourth embodiment.

The second salient points in the embodiment can be connected to form a regular arrangement structure, and can also be processed to form an irregular edge structure as required. In addition, the second salient point of the present embodiment may be formed in a hemispherical shape or a square shape, which can increase the friction force between the sampling swab and the second cavity 12 when the sampling swab moves up and down or rotates.

EXAMPLE six

The present embodiment is the same as any one of the first to fifth embodiments, except that the first cavity 11 of the present embodiment is a tapered hole, the second cavity 12 is a cylindrical hole, and the depth of the second cavity 12 is greater than the depth of the first cavity 11, as shown in fig. 4. The first cavity 11 is provided with a conical hole, so that the sample releasing agent can be favorably collected in the first cavity 11, the liquid level depth of the sample releasing agent can be increased, and the subsequent detection and sampling can be favorably realized; the depth of the second cavity 12 is larger than that of the first cavity 11, the bottom of the second cavity 12 is located below the bottom of the first cavity 11, and the sampling swab can stably stand in the second cavity 12, so that the influence of sampling swab toppling on detection sampling operation is prevented.

EXAMPLE seven

The present embodiment is the same as any one of the first to fifth embodiments, except that the first cavity 11 of the present embodiment is a tapered hole, the second cavity 12 is a cylindrical hole, a diameter of the first cavity 11, the second cavity 12 and the tube 1 are collinear, the first cavity 11 and the second cavity 12 are partially overlapped to form a first side edge and a second side edge, and a distance between the first side edge and the second side edge is not greater than a minimum diameter of the sampling swab, as shown in fig. 10. During implementation, the communication between the first cavity 11 and the second cavity 12 is not affected, the sample releasing agent can freely flow between the first cavity 11 and the second cavity 12, and the sampling swab in the second cavity 12 can be effectively prevented from inclining to one side of the first cavity 11. It should be noted that the gap between the first side edge and the second side edge is preferably made for obtaining good processing performance and stabilizing the sampling swab, and is not regarded as the utility model discloses a regulation, the utility model discloses still can be through connecting the curb plate between first side edge, second side edge, design hole or hole groove on the curb plate to play the effect of preventing the sampling swab slope when realizing communicating first cavity 11, second cavity 12.

It is obvious that the above embodiments of the present invention are only examples for clearly illustrating the present invention, and are not limitations to the embodiments of the present invention. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. The utility model provides a save tube for sampling swab, includes body (1), its characterized in that, be equipped with in body (1) and be used for storing first cavity (11) of sample release agent and be used for placing sampling swab's second cavity (12), first cavity (11) and second cavity (12) intercommunication set up, the central axis of second cavity (12) deviate from in the central axis of body (1).

2. The storage tube for sampling swabs as claimed in claim 1, wherein the central axis of the first cavity (11) coincides with the central axis of the tube (1), and the side of the second cavity (12) is attached to the inner wall of the tube (1).

3. The storage tube for sampling swabs as claimed in claim 1, wherein the top of the tube body (1) is provided with a first connecting part (13) for connecting the tube cover (2), and the bottom of the tube body (1) is provided with a fixing part (14).

4. The storage tube for sampling swabs as claimed in claim 1, wherein the top of the first cavity (11) and the second cavity (12) is connected with a second connecting part (15), and the second connecting part (15) surrounds between the outer edges of the top of the first cavity (11) and the second cavity (12) and the inner wall of the tube body (1).

5. A storage tube for sampling swabs according to claim 1, characterized in that the inner wall of the second chamber (12) is provided with a plurality of first protrusions (16).

6. The storage tube for sampling swabs as claimed in claim 5, wherein the first convex part (16) is a first rib or a first convex point, and the first rib is one or a combination of vertical rib, horizontal rib, oblique rib and spiral rib.

7. The storage tube for sampling swabs as claimed in claim 5, wherein a plurality of second protrusions (17) are uniformly distributed on the bottom of the inner side of the second cavity (12).

8. A holding tube for a sampling swab according to claim 7, wherein the second protrusion (17) is a second ridge or a second protrusion, one end of the second ridge is arranged at the center of the bottom of the second cavity (12), and the other end of the second ridge is connected to the first protrusion (16).

9. A storage tube for a sampling swab according to any one of claims 1 to 8, wherein the first cavity (11) is a tapered hole and the second cavity (12) is a cylindrical hole, the depth of the second cavity (12) being greater than the depth of the first cavity (11).

10. The storage tube for sampling swabs according to any of claims 1 to 8, characterized in that the first cavity (11) is a tapered hole, the second cavity (12) is a cylindrical hole, the first cavity (11) and the second cavity (12) are partially overlapped to form a first side edge and a second side edge, and the distance between the first side edge and the second side edge is not more than the minimum diameter of the sampling swab.