Devices and methods for blood collection

Abstract

Disclosed herein are devices and methods for blood collection. A device may be provided having a base member configured to sealably attach to a skin region of an individual, the base member having a lancet port sized to fit a lancet therethrough to puncture the skin region; a top member configured to be mounted onto the base member to define a sealed chamber over the skin region; a vacuum port configured to couple with a vacuum source; and a collection reservoir configured to be in fluid communication with the sealed chamber. Application of the vacuum source to provide a pressure less than atmospheric pressure at the vacuum port urges blood to flow from the skin region, when punctured, into the collection reservoir.

Description

DEVICES AND METHODS FOR BLOOD COLLECTIONCROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims the benefit of and priority to U.S. provisional patent application no. 63 / 550,801 filed February 7, 2024, the entire content of which is herein incorporated by reference.TECHNICAL FIELD

[0002] The present disclosure relates to sampling blood from the body for analysis or processing.BACKGROUND

[0003] Traditional methods of blood collection that require the use of large gauge lancets in sensitive areas (e.g., fingertips) can cause mild to significant discomfort. In addition, the total volume of blood extracted using these methods is often low (~30-45 microlitres per drop). The limited volume of blood extracted using these methods can be a significant limitation, particularly in cases where larger blood samples are required for analysis or processing. These methods may also require an individual to apply excessive pressure on the finger to promote blood flow ( / .e., milking the finger). Excessive pressure during blood collection can trigger hemolysis, which can render many clinical results inaccurate. Improvement is desirable.SUMMARY

[0004] In one aspect, this disclosure describes a blood collection device. The blood collection device includes a base member configured to sealably attach to a skin region of an individual, the base member having a lancet port sized to fit a lancet therethrough to puncture the skin region; a top member configured to be mounted onto the base member to define a sealed chamber over the skin region; a vacuum port configured to couple with a vacuum source; and a collection reservoir configured to be in fluid communication with the sealed chamber; wherein application of the vacuum source to provide a pressure less than atmospheric pressure at the vacuum port urges blood to flow from the skin region, when punctured, into the collection reservoir.

[0005] In such device, the vacuum source may include at least one of a vacutainer a syringe-style vacuum pull, or a compression of a rubber dome with a one-way valve.

[0006] In such device, the top member may be mountable onto the base member using a threading mechanism.

[0007] In such device, the collection reservoir may include a capillary tube.

[0008] In such device, the capillary tube may be disposed in either the top member or the base member to be within the sealed chamber when the top member is mounted onto the base member.

[0009] In such device, the capillary tube may be external to the blood collection device and be attachable to the blood collection device via an outlet port in fluid communication with the sealed chamber.

[0010] In such device, at least a portion of the capillary tube may be coated with an anti-coagulant to prevent the formation of blood clots.

[0011] In such device, the capillary tube may have an end that contains a hydrophobic porous material to allow the displacement of air.

[0012] In such device, at least a portion of an inner surface of the top member may be coated with an anti-coagulant to prevent the formation of blood clots.

[0013] In such device, at least a portion of an inner surface of the base member may be coated with an anti-coagulant to prevent the formation of blood clots.

[0014] In such device, at least a portion of an outer surface of the base member may be coated with an adhesive material for attachment to the skin region.

[0015] In such device, an outer surface of the base may be configured to be attached to a skin region of an arm.

[0016] Embodiments may include combinations of the above features.

[0017] In another aspect, this disclosure describes a method of sampling blood from a user using a blood collection device having a base member and top member. The method includes sealably attaching the base member onto a skin region of an individual; inserting a lancet through a lancet port of the base member to puncture the skin region; withdrawing the lancet from the base member; mounting the top member onto the base member to define a sealed chamber over the skin region; and generating a pressure less than atmospheric pressure within the sealed chamber to urge blood from the punctured skin region into a collection reservoir in fluid communication with the sealed chamber.

[0018] In such method, the generating may include applying a vacutainerto a vacuum port of the blood collection device.

[0019] In such method, the mounting may include fastening the top member onto the base member using a threading mechanism.

[0020] In such method, the skin region may be on an arm of the individual.

[0021] In such method the collection reservoir may include a capillary tube.

[0022] In such method, the method may further include selecting a size of the collection reservoir.

[0023] In such method, the method may further include extracting a desired volume of blood from the collection reservoir by contact with a porous filter material.

[0024] In such method, the method may further include extracting a desired volume of blood from the collection reservoir by operation of gravity.

[0025] Embodiments may include combinations of the above features.

[0026] Further details of these and other aspects of the subject matter of this application will be apparent from the detailed description included below and the drawings.DESCRIPTION OF THE DRAWINGS

[0027] Reference is now made to the accompanying drawings, in which:

[0028] FIG. 1 is a front view of a blood collection device, in accordance with an embodiment;

[0029] FIG. 2 is a top view of a base member of the blood collection device of FIG. 1 , in accordance with an embodiment;

[0030] FIG. 3 is a front view of a blood collection device with an integrated capillary, in accordance with an embodiment;

[0031] FIG. 4 is a flow diagram of an exemplary method for collecting blood using the blood collection device shown in FIG. 1 , in accordance with an embodiment.DETAILED DESCRIPTION

[0032] Before any embodiments are explained in detail, it is to be understood that the disclosure is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the accompanying drawings. The disclosure is capable of other embodiments and of being practiced or of being carried out in various ways.

[0033] The following description discloses a blood collection device and associated methods for obtaining a sample of blood from a body portion such as a limb.

[0034] In some embodiments, a blood collection device disclosed herein can collect a volume of blood that is significantly greater than the volume of blood collected using traditional methods such as finger pricking. In some embodiments, a blood collection device disclosed herein may be capable of collecting greaterthan 200 microlitres of blood in under 5 minutes. The increased volume of blood collected using the blood collection device described herein can advantageously allow for a wider range of testing and analysis.

[0035] In some embodiments, a blood collection device disclosed herein can provide moderate and uniform pressure in the form of a vacuum when collecting blood from the limb. In some embodiments, pressure applied by the blood collection device may be less than a pressure that would trigger hemolysis. Conveniently, the integrity of the blood sample collected can be preserved for analysis or processing.

[0036] Conveniently, a blood collection device disclosed herein is operable by and the associated methods can be performed by a single user, e.g., to obtain a sample of his / her own blood.

[0037] In some embodiments, a blood collection device may include a base member, a top member, and a vacuum port. The base member may include an outer surface that is configured to sealably attach to a skin region of a user, e.g., on an arm of the user. A lancet port may be defined on the outer surface that is sized to fit a lancet therethrough. After the lancet is used to puncture the limb, the top member may be mounted onto the base member. Conveniently, a commercially available lancet may be used. A lancet of an appropriate gauge may be selected by the user.

[0038] The top member and base member may define a sealed chamber therebetween. The blood collection device may include a vacuum port configured to couple with a vacuum source. The vacuum source may be a commercially available vacutainer. The blood collection device may include a collection reservoir in fluid communication with the sealed chamber. Application of the vacuum source to provide a pressure less than atmospheric pressure at the vacuum port urges blood to flow from the skin region, when punctured, into the collection reservoir. In some embodiments, a syringe-style vacuum pull and / or a compression of a rubber dome with a one-way valve may be used instead of a vacutainer or in combination with a vacutainer.

[0039] In some embodiments, the collection reservoir is in fluid communication with a capillary tube. In some embodiments, the collection reservoir includes a capillary tube.

[0040] The term “connected” or "coupled to" may include both direct coupling (in which two elements that are coupled to each other and contact each other) and indirect coupling (in which at least one additional element is located between the two elements).

[0041] The singular forms "a," "an," and "the" include the plural reference unless the context clearly dictates otherwise. The term "and / or" means any one of the items, any combination of the items, or all of the items with which this term is associated.

[0042] Aspects of various embodiments are described through reference to the drawings.

[0043] Referring now to FIG. 1 , an embodiment of a blood collection device 10 attached to a limb 30 is illustrated. Blood collection device 10 may be used for drawing blood from limb 30 of an individual into a collection reservoir 20.

[0044] Blood collection device 10 may include base member 12 and top member 28. Base member 12 may have outer surface 13 that attaches to limb 30. Outer surface 13 may be coated with an adhesive that is safe for skin contact. When outer surface 13 is applied onto limb 30, outer surface 13 may adhere to the skin of limb 30 to seal base member 12 to limb 30. Outer surface 13 may be shaped to at least partially conform to the surface of limb 30. In some embodiments, outer surface 13 may be an elastic or rubber surface that is flexible to conform to the surface of limb 30.

[0045] As best seen in FIG. 2, blood collection device 10 may have lancet port 15 defined on outer surface 13 of base member 12. Lancet port 15 may be sized to fit a commercial lancet 26 therethrough to puncture the skin of limb 30. In some embodiments, lancet 26 may be inserted through lancet port 15 to puncture the skin of limb 30 after base member 12 is attached to limb 30. The gauge size of lancet 26 may be selected by the user from commercially available gauge sizes. In some applications, lancet 26 may have a large gauge size.

[0046] Top member 28 may be configured to be installed onto base member 12 after lancet 26 has punctured the skin and has been withdrawn from base member 12. In some embodiments, top member 28 may be fastened onto base member 12 using a threading mechanism. Top member 28 may have threads defined on an inner or outer surface of top member 28 that are configured to align with corresponding threads defined on an outer or inner surface of base member 12. While the present application contemplates installing top member 28 to base member 12 using a threading mechanism, it should be understood that other mechanisms could be employed that permit top member 28 to be sealably attached to base member 12 manually, without the need of specialty equipment.

[0047] Blood collection device 10 may include vacuum port 14 and outlet port 16. In some embodiments and as depicted, vacuum port 14 and outlet port 16 may form part of base member 12. Vacuum port 14 and outlet port 16 may be in fluid communication with open chamber 17 of base member 12.

[0048] Lancet port 15 may also be in fluid communication with open chamber 17. When top member 28 is installed onto base member 12, top member 28 may close an exposed opening 19 defined in base member 12 to define sealed chamber 18 between top member 28 and base member 12.

[0049] While FIG. 1 illustrates vacuum port 14, outlet port 16, and chamber 17 forming part of base member 12, it should be understood that these components could alternatively form part of top member 28. In this embodiment, base member 12 may define one or more cavities and one or more openings for accommodating these components when top member 28 is installed onto base member 12.

[0050] Vacuum port 14 may be configured to couple with a commercial vacutainer 22. Vacutainer 22 may be a plastic or glass tube having an internal pressure less than atmospheric pressure. For example, vacutainer 22 may be a BD® vacutainer with a BD® Safety-Lok. In one specific embodiment, vacutainer 22 is a 10 mL BD® vacutainer providing a pressure approximately 75 mm of Hg less than atmospheric pressure, which is approximately 760 mm of Hg.

[0051] In some embodiments, vacuum port 14 may be sized to receive and seal at least a portion of vacutainer 22 within vacuum port 14. In some embodiments, vacuum port 14 is configured to receive at least a portion of vacutainer 22, e.g., a safety lock portion, via a press fit. The safety lock may include a sealed needle that pierces through a rubber septum in a cap of vacutainer 22 when vacutainer 22 is pushed into it, forming a substantially airtight seal. The safety lock may be shaped to hold vacutainer 22 in position when pierced. In some embodiments, vacuum port 14 may include a rubber seal to seal the portion of vacutainer 22 that has been press fitted, to prevent an air leak.

[0052] As discussed in greater detail below, vacutainer 22 may be used to generate a vacuum within sealed chamber 18 when sealed chamber 18 is closed to draw blood from the puncture site into sealed chamber 18.

[0053] Outlet port 16 may be configured to couple with reservoir 20. In some embodiments, reservoir 20 may be coupled to outlet port 16 after top member 28 is installed onto base member 12 but before vacutainer 22 is coupled to vacuum port 14.Reservoir 20 may be coupled to outlet port before creating a vacuum using vacutainer 22. Reservoir 20 may be held in place using rubber seals along the inner edge of outlet port 16 to maintain a substantially airtight seal. After creating a vacuum and filling chamber 17, capillary action may draw blood into reservoir 20 filling it with a controlled volume of blood. Reservoir 20 may then be replaced with a fresh reservoir to collect more controlled volumes of blood as long as there is more blood collected in chamber 17. Leakage through outlet port 16 may be prevented by lining it with a hydrophobic rubber seal.

[0054] Reservoir 20 may define an internal volume for collecting a sample of blood. As depicted, reservoir 20 may include first end 21 A that is opened and that is configured to couple with outlet port 16 and second end 21 B that is selectively closed to contain the blood. In some embodiments, first end 21 A may be coupled to outlet port 16 using a threading mechanism. However, it should be understood that other securing methods could be employed.

[0055] In some embodiments, reservoir 20 may include a capillary tube. The capillary tube may be a thin high-precision glass tube that uses capillary action to draw up a controlled volume of blood. The length and diameter of the capillary tube may dictate the total volume of blood collected by blood collection device 10. The size of the capillary tube chosen may be selected based on the specific volume of blood required for a particular analysis or test. The size of the capillary tube may match the vacuum capacity of vacutainer 22. The capillary tube may be coated with an anti-coagulant to prevent the formation of blood clots in the blood collected. In some embodiments, at least a portion of an inner surface of the top member 28 and / or at least a portion of an inner surface of the base member 12 may coated with such anti-coagulant.

[0056] The capillary tube may contain a hydrophobic porous material at end 21 B to allow air to be displaced during blood uptake, but to prevent blood spillage once the capillary tube has reached a maximum capacity.

[0057] In some embodiments, the capillary tube of reservoir 20 may be replaced or supplemented by one or more other devices configured to receive a volume of blood. Such devices may include, for example, capillary locked cups, filter paper, lateral flowstrips, syringes, pipette tips, or the like. Outlet port 16 may be configured with a shape to form a substantially airtight seal with one or more such other devices. Some of these devices may use active forces like the pipette tips and syringes to draw blood out from chamber 18.

[0058] In some embodiments, it might be possible to run or load assays directly from chamber 18, and reservoir 20 may be omitted. In such cases, a sample of blood may be drawn from chamber 18 using suitable lateral flow strips, microfluidic chips, or the like.

[0059] Sealed chamber 18 may be a closed system after top member 28 has been installed onto base member 12, collection reservoir 20 has been coupled to outlet port 16, and vacutainer 22 has been coupled to vacuum port 14. In this configuration, vacutainer22 may generate a vacuum ( / .e., negative pressure) within sealed chamber 18 causing blood to be drawn from the puncture site into sealed chamber 18. The blood drawn into sealed chamber 18 may then be directed using capillary forces into the capillary tube. The capillary forces is the result of the blood's inherent surface adhesion (intermolecular attraction to dissimilar molecules) and cohesion (attraction to similar molecules). The blood's adhesion to the inner wall of the capillary tube causes the blood to be forced towards second end 21 B of the capillary tube.

[0060] In some embodiments, blood collection device 10 may be configured so that when placed on the upper arm, it is oriented with outlet port 16 facing down, allowing gravity to help direct flow in chamber 18 towards the outlet port 16. In cases where outlet port 16 is coupled to a capillary tube, this orientation may also aid capillary flow.

[0061] In some embodiments, reservoir20 may be disposed in eithertop member 28 or base member 12 to be within sealed chamber 18 when top member 28 is mounted onto base member 12, or otherwise be integral with the blood collection device. FIG. 3 depicts a blood collection device 10’ having an integral capillary nozzle 120. Capillary nozzle 120 may have a volume (e.g., length and diameter) selected based on the desired volume of blood to be collected. Capillary nozzle 120 may have a first end 121 A in fluid communication with chamber 17 and a second end 121 B for dispensing blood out of blood collection device 10’. End 121 B may be selectively sealed by a rubber cap 122. During operation, cap 122 may be removed to allow a user to begin filling the capillarynozzle. In some embodiments, cap 122 may be replaced by a rubber stopper or other suitable sealing device. Inclusion of capillary nozzle 120 avoids the need for a separate capillary tube and / or collection reservoir 20. Blood collection device 10’ may be otherwise substantially similar to blood collection device 10.

[0062] FIG. 4 is a flow diagram of an exemplary method 100 for obtaining a sample of blood from a user. Method 100 may be performed using blood collection device 10 described herein or using other systems. It should be understood that aspects of method 100 may be combined with aspects of other methods described herein. In the depicted embodiment, method 100 includes:

[0063] At block 102, sealably attaching base member 12 onto a skin region of a limb 30 of an individual.

[0064] At block 104, inserting lancet 26 through a lancet port 15 of the base member to puncture the skin region.

[0065] At block 106, withdrawing lancet 26 from base member 12.

[0066] At block 108, mounting top member 28 onto base member 12 to define a sealed chamber 18 over the skin region.

[0067] At block 110, generating a pressure less than atmospheric pressure within sealed chamber 18 to urge blood from the punctured skin region into a collection reservoir 20 in fluid communication with sealed chamber 18.

[0068] In some embodiments, after installing the top member 28 onto the base member 12 and before generating the vacuum within the sealed chamber 18, method 100 may include coupling the collection reservoir 20 to the outlet port 16.

[0069] In some embodiments, installing the top member 28 onto the base member 12 may involve fastening the top member 28 onto the base member 12 using a threading mechanism.

[0070] In some embodiments, the reservoir 20 includes a capillary tube. The capillary tube may be coated with an anti-coagulant to prevent the formation of blood clots. Thecapillary tube may have end 21 B that contains a hydrophobic porous material. Method 100 may include displacing air from the blood collected in the capillary tube via the second end 21 B.

[0071] In some embodiments, method 100 includes selecting a size of the collection reservoir based on the desired volume of blood to be collected. This may include selecting a capillary tube of a desired volume (e.g., length and diameter).

[0072] In some embodiments, at least a portion of the outer surface 13 of the base member 12 is coated with an adhesive material. Sealably attaching the outer surface 13 of the base member 12 to the limb 30 may involve adhering the outer surface 13 of the base member 12 to the skin of the limb 30.

[0073] In some embodiments, blood collection device 10 may be configured to be placed on a body portion other than an upper arm.

[0074] In some embodiments, method 100 includes extracting a desired volume of blood from the collection reservoir by contact with a porous filter material.

[0075] In some embodiments, method 100 includes extracting a desired volume of blood from the collection reservoir by operation of gravity.

[0076] The above description is meant to be exemplary only, and one skilled in the relevant arts will recognize that changes may be made to the embodiments described without departing from the scope of the invention disclosed. The present disclosure may be embodied in other specific forms without departing from the subject matter of the claims. The present disclosure is intended to cover and embrace all suitable changes in technology. Modifications which fall within the scope of the present invention will be apparent to those skilled in the art, in light of a review of this disclosure, and such modifications are intended to fall within the appended claims. Also, the scope of the claims should not be limited by the preferred embodiments set forth in the examples, but should be given the broadest interpretation consistent with the description as a whole.

[0077] As can be understood, the detailed embodiments described above and illustrated are intended to be examples only. The invention is defined by the appended claims.

[0078] The claims are not intended to include, and should not be interpreted to include, means-plus- or step-plus-function limitations, unless such a limitation is explicitly recited in a given claim using the phrase(s) “means for” or “step for,” respectively.

Claims

WHAT IS CLAIMED IS:1 . A blood collection device comprising: a base member configured to sealably attach to a skin region of an individual, the base member having a lancet port sized to fit a lancet therethrough to puncture the skin region; a top member configured to be mounted onto the base member to define a sealed chamber over the skin region; a vacuum port configured to couple with a vacuum source; and a collection reservoir configured to be in fluid communication with the sealed chamber; wherein application of the vacuum source to provide a pressure less than atmospheric pressure at the vacuum port urges blood to flow from the skin region, when punctured, into the collection reservoir.

2. The blood collection device of claim 1 , wherein the vacuum source includes at least one of a vacutainer, a syringe-style vacuum pull, or a compression of a rubber dome with a one-way valve.

3. The blood collection device of claim 1 , wherein the top member is mountable onto the base member using a threading mechanism.

4. The blood collection device of claim 1 , wherein the collection reservoir includes a capillary tube.

5. The blood collection device of claim 4, wherein the capillary tube is disposed in either the top member or the base member to be within the sealed chamber when the top member is mounted onto the base member.

6. The blood collection device of claim 4, wherein the capillary tube is external to the blood collection device and is attachable to the blood collection device via an outlet port in fluid communication with the sealed chamber.

7. The blood collection device of claim 4, wherein at least a portion of the capillary tube is coated with an anti-coagulant to prevent the formation of blood clots.

8. The blood collection device of claim 4, wherein the capillary tube has an end that contains a hydrophobic porous material to allow the displacement of air.

9. The blood collection device of claim 1 , wherein at least a portion of an inner surface of the top member is coated with an anti-coagulant to prevent the formation of blood clots.

10. The blood collection device of claim 1 , wherein at least a portion of an inner surface of the base member is coated with an anti-coagulant to prevent the formation of blood clots.11 . The blood collection device of claim 1 , wherein at least a portion of an outer surface of the base member is coated with an adhesive material for attachment to the skin region.

12. The blood collection device of claim 1 , wherein an outer surface of the base is configured to be attached to an arm.

13. A method of sampling blood from a user using a blood collection device, the blood collection device includes a base member and top member, the method comprising: sealably attaching the base member onto a skin region of an individual; inserting a lancet through a lancet port of the base member to puncture the skin region; withdrawing the lancet from the base member;mounting the top member onto the base member to define a sealed chamber over the skin region; and generating a pressure less than atmospheric pressure within the sealed chamber to urge blood from the punctured skin region into a collection reservoir in fluid communication with the sealed chamber.

14. The method of claim 13, wherein said generating includes applying a vacutainer to a vacuum port of the blood collection device.

15. The method of claim 13, wherein said mounting includes fastening the top member onto the base member using a threading mechanism.

16. The method of claim 13, wherein said skin region is on an arm of the individual.

17. The method of claim 13, wherein the collection reservoir includes a capillary tube.

18. The method of claim 13, further comprising selecting a size of the collection reservoir.

19. The method of claim 13, further comprising extracting a desired volume of blood from the collection reservoir by contact with a porous filter material.

20. The method of claim 13, further comprising extracting a desired volume of blood from the collection reservoir by operation of gravity.

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