Patent Application
20220370047
The present invention relates to the field of fluid volume sampling devices, and in particular to devices for sampling small initial volumes of a liquid flow.
With the development of highly sensitive nucleic acid amplification testing of pathogenic DNA, self-collected first-void urine has become a valuable non-invasive sample for diagnostic purposes, for instance for the detection of urogenital infections such as Chlamydia trachomatis, as well as other sexually transmitted infections. Results of this testing method, however, are only conclusive if the sampled urine fraction is not diluted or contaminated by the subsequent mid-stream urine. Moreover, even within the first-void volume of urine, there are variations of the microorganism load in urine samples which depend on the precise initial volume sampled, e.g. only a small fraction of the first-void urine. Therefore, a need for liquid sampling devices exists which allow the precise sampling of an initial volume of a liquid flow, e.g. urine, and which are hygienic and comfortable in their use.
WO2014/037152 relates to a liquid sampling device for capturing a first portion of a liquid flow. The device comprises an inlet, an outlet, and a guide with a displaceable element which, in a first position, is capturing a first portion of the liquid flow, e.g. the first-void urine, into a reservoir, and which, in a second position, is blocking the access to the reservoir and is passing subsequent liquid to the outlet instead. The displaceable element moves in transverse direction to the liquid flow and has lifting means. Although being suitable for the sampling of first-void urine, it remains challenging for this device to restrict the quantity of sampled first-void urine to a small initial volume fraction thereof.
Miniaturizing buoyancy-driven liquid sampling devices described in WO2014/037152 A1 to make them fit to smaller volumes as required for diagnostics is challenging because the buoyancy force necessary to elevate the displaceable element (e.g. a valve) is strongly reduced for smaller-sized lifting means, such as air pockets or floaters, which still fit into the sampling receptacles. Another problem faced by miniaturization is the limited wall thickness that is yet obtainable by injection molding techniques, e.g. limited to 0.5 mm. There are indeed chances that designs with limited use of material, thus very thin-walled designs, with a wall thickness below 0.5 mm, e.g. 0.4 mm thick or thinner, are facing filling issues in the mold when they are injection molded. Further, the redirection of the sampled liquid volume through tubular ducts of small diameter is slow and possibly dominated by capillary action, which can result in liquid rapidly accumulating in the chamber (e.g. guide portion) connected between the inlet and outlet conduits. As liquid is held back and rises in the chamber, the inflow of the initial fraction is hampered and retarded. Ultimately, the subsequent volume may dilute or mix or contaminate with the initial volume to be sampled if the latter is not drained fast enough.
It is therefore an object of embodiments of the present invention to provide a device for sampling an initial volume of a liquid flow, hygienic and comfortable in use, which is also adapted for reliably sampling small initial volumes, e.g. volumes smaller than 20 ml, e.g. about 5 ml or less. The above objective is accomplished by a device and a kit of parts according embodiments of to the present invention.
In one aspect the invention relates to a device for sampling an initial volume of a liquid flow and the device comprises an inlet conduit for receiving the liquid flow, an outlet conduit for draining a subsequent volume of the liquid flow, and a valve casing arranged between the inlet conduit and the outlet conduit. The valve casing has a passageway formed therethrough to fluidly connect the inlet conduit to the outlet conduit, for instance is providing an inlet and an outlet through a projecting sidewall. A sample outlet for draining the initial volume of the liquid flow is extending through the valve casing and into said passageway. Further, a valve structure is arranged for axial movement in the valve casing, traverse to a direction of liquid flow through the passageway. The valve structure comprises a gate for obstructing the passageway and for preventing the initial volume of the liquid flow from being transferred to the outlet conduit when the valve structure is in, e.g. moved to, a sampling position. Besides, the valve structure comprises a stem which is connected to the gate and adapted for obstructing the sample outlet without obstructing the passageway when the valve structure is in, e.g. moved to, a diverting position. At least one elongated groove is formed in a surface of the gate that faces the inlet conduit. The at least one groove extends from the gate into the stem such that the initial volume of the liquid flow is directed through the sample outlet and towards a receptacle, which is connectable to the valve casing, when the valve structure is in, e.g. moved to, the sampling position. The at least one elongated groove forms a narrow channel in the gate and the stem, which is fit to receive the inflowing initial volume and to guide it in a downward movement along the gate and the stem, and through the sample outlet if the valve structure is moved to the sampling position. The at least one elongated groove thus enables a liquid passageway for the initial volume flow between the inlet conduit and the sample outlet when the valve structure is in the sampling position. Moreover, a lifting member is connected to the stem for moving the valve structure from the sampling position to the diverting position while the initial volume of the liquid flow is being sampled through the sample outlet.
According to some embodiments of the present invention, the gate includes a slanted wall for achieving obstruction of the passageway through the valve casing and for obtaining an additional lifting force at the same time.
In some embodiments of the present invention, a resilient stopper is protruding from the inner surface of the valve casing to prevent a vertical displacement of the valve structure beyond the diverting position. Various height positions of the stopper can be determined to match a predetermined initial volume that is sampled in standardized receptacles, e.g. test tubes.
In some embodiments of the present invention, the rim of the cap and/or the outer edge of a lower portion of the stem is fitted (e.g. complementary in size and shape) to lie flush with a corresponding surface of the valve casing and the bore of the sample outlet respectively. This provides an efficient sealing effect.
In some embodiments of the present invention, the cap and/or ribbed edges of the valve structure are in a telescopic relationship with the inner surface of the valve casing and the bore of the sample outlet respectively. This improves a sliding axial movement of the valve structure relative to the valve casing by a guiding assistance at reduced friction.
According to some embodiments of the present invention, the cap has an asymmetrical shape (e.g. defined by its rim) to prevent a rotation movement of the valve structure around its axis of translation. Hereto, the valve structure may have a mating asymmetrical shape.
It is an advantage of embodiments of the present invention that the device can cope with a wide range of volumetric flow rates, including volumetric flow rates typical for urination, e.g. ranging from 1 ml/sec to 55 ml/sec.
It is an advantage of embodiments of the present invention that components of the device may be composed of biodegradable polymers or other suitable biomaterials, which can be readily disposed of after use.
It is an advantage of embodiments of the present invention that inlet conduits and/or funnels can be adapted for use by a specific gender. This increases user comfort and also reduces the risk of spillage.
It is an advantage of embodiments of the present invention that the components of the sampling device can be manufactured separately and assembled later. Hence, the components of the sampling device can be sent to the user as a kit of parts, involving only little shipment costs and the user can take samples at home.
In a further aspect the invention relates to a kit of parts, for assembling a device according to embodiments of the first aspect, which comprises a bonnet with at least three openings, an inlet conduit that is connectable to a first opening of the bonnet, an outlet conduit that is connectable to a second opening of the bonnet, and a valve casing that is removably insertable into the bonnet via a third opening therein. A base of the valve casing is connectable to the third opening, and the valve casing has an inlet and an outlet formed therethrough, defining a liquid passageway though the valve casing. A sample outlet extends through the base of the valve casing and into the passageway. Additionally, the valve casing has an opening provided at a top side, opposite to the base through which a valve structure is insertable. A valve structure, also included in the kit, is removably insertable into the valve casing. The valve structure is arranged for axial movement in the valve casing, traverse to a direction of liquid flow through the passageway. A gate of the valve structure is configured for obstructing the passageway when the valve structure is in, e.g. moved to, a sampling position, a stem of the valve structure is connected to the gate and adapted for obstructing the sample outlet without obstructing the passageway when the valve structure is in, e.g. moved to, a diverting position. At least one elongated groove is formed in a surface of the gate and extends into the stem. Moreover, the kit includes a lifting member that is connectable to the stem.
Alternatively, a kit of parts comprises a valve casing with an inlet and an outlet formed therethrough, defining a liquid passageway through the valve casing. The kit further comprises a sample outlet which extends through a base of the valve casing and into the passageway, and an inlet conduit and outlet conduit which are connectable to the inlet and the outlet of the valve casing respectively. An opening is provided at a top side of the valve casing, opposite to the base. Besides, a valve structure is included in the kit which is removably insertable into the valve casing. The valve structure is arranged for axial movement in the valve casing, traverse to a direction of liquid flow through the passageway. A gate of the valve structure is adapted for obstructing the passageway when the valve structure is in, e.g. moved to, a sampling position, and a stem of the valve structure is connected to the gate and adapted for obstructing the sample outlet without obstructing the passageway when the valve structure is in, e.g. moved to, a diverting position. At least one elongated groove is formed in a surface of the gate and extends from the gate into the stem. Furthermore, the kit comprises a lifting member that is connectable to the stem.
Particular and preferred aspects of the invention are set out in the accompanying independent and dependent claims. Features from the dependent claims may be combined with features of the independent claims and with features of other dependent claims as appropriate and not merely as explicitly set out in the claims.
For purposes of summarizing the invention and the advantages achieved over the prior art, certain objects and advantages of the invention have been described herein above. Of course, it is to be understood that not necessarily all such objects or advantages may be achieved in accordance with any particular embodiment of the invention. Thus, for example, those skilled in the art will recognize that the invention may be embodied or carried out in a manner that achieves or optimizes one advantage or group of advantages as taught herein without necessarily achieving other objects or advantages as may be taught or suggested herein.
The above and other aspects of the invention will be apparent from and elucidated with reference to the embodiment(s) described hereinafter.
The invention will now be described further, by way of example, with reference to the accompanying drawings, in which:
In the drawings, the size of some of the elements may be exaggerated and not drawn on scale for illustrative purposes. The dimensions and the relative dimensions do not necessarily correspond to actual reductions to practice of the invention.
Any reference signs in the claims shall not be construed as limiting the scope.
In the different drawings, the same reference signs refer to the same or analogous elements.
The present invention will be described with respect to particular embodiments and with reference to certain drawings but the invention is not limited thereto but only by the claims.
Moreover, directional terminology such as top, bottom, front, back, leading, trailing, under, over and the like in the description and the claims is used for descriptive purposes with reference to the orientation of the drawings being described, and not necessarily for describing relative positions. Because components of embodiments of the present invention can be positioned in a number of different orientations, the directional terminology is used for purposes of illustration only, and is in no way intended to be limiting, unless otherwise indicated. It is, hence, to be understood that the terms so used are interchangeable under appropriate circumstances and that the embodiments of the invention described herein are capable of operation in other orientations than described or illustrated herein.
It is to be noticed that the term “comprising”, used in the claims, should not be interpreted as being restricted to the means listed thereafter; it does not exclude other elements or steps. It is thus to be interpreted as specifying the presence of the stated features, integers, steps or components as referred to, but does not preclude the presence or addition of one or more other features, integers, steps or components, or groups thereof. Thus, the scope of the expression “a device comprising means A and B” should not be limited to devices consisting only of components A and B. It means that with respect to the present invention, the only relevant components of the device are A and B.
Reference throughout this specification to “one embodiment” or “an embodiment” means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, appearances of the phrases “in one embodiment” or “in an embodiment” in various places throughout this specification are not necessarily all referring to the same embodiment, but may. Furthermore, the particular features, structures or characteristics may be combined in any suitable manner, as would be apparent to one of ordinary skill in the art from this disclosure, in one or more embodiments.
Similarly it should be appreciated that in the description of exemplary embodiments of the invention, various features of the invention are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the disclosure and aiding in the understanding of one or more of the various inventive aspects. This method of disclosure, however, is not to be interpreted as reflecting an intention that the claimed invention requires more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive aspects lie in less than all features of a single foregoing disclosed embodiment. Thus, the claims following the detailed description are hereby expressly incorporated into this detailed description, with each claim standing on its own as a separate embodiment of this invention.
Furthermore, while some embodiments described herein include some but not other features included in other embodiments, combinations of features of different embodiments are meant to be within the scope of the invention, and form different embodiments, as would be understood by those in the art. For example, in the following claims, any of the claimed embodiments can be used in any combination.
It should be noted that the use of particular terminology when describing certain features or aspects of the invention should not be taken to imply that the terminology is being re-defined herein to be restricted to include any specific characteristics of the features or aspects of the invention with which that terminology is associated.
In the description provided herein, numerous specific details are set forth. However, it is understood that embodiments of the invention may be practiced without these specific details. In other instances, well-known methods, structures and techniques have not been shown in detail in order not to obscure an understanding of this description.
When reference is made in embodiments of the invention to a first-void volume of urine, this generally designates the first 20 ml to 50 ml of the initial urine flush. Small volumes in this respect, refer to volumes of first-void volume which are smaller than 20 ml, e.g. less than 10 ml, e.g. less than 5 ml, such as for instance 4 ml.
With reference to
The valve structure 17, as shown in
The sampling position, which is illustrated in
This obstruction mechanism of the gate 14 of the valve structure in the sampling position can be more readily understood by referring to
As mentioned, the initial volume is prevented from entering the outlet conduit 11, hence well-preserved for sampling, if the valve structure 17 is moved to the sampling position and the passageway between the inlet 13a and the outlet 13b of the valve casing is blocked. However, there exists a fluid connection between the inlet 13a and the sample outlet 13c as long as the initial volume of the liquid flow is received and sampled. More specifically, the at least one groove 14a formed in the wall 14b of the gate 14 ensures that the received initial volume is redirected towards the sample outlet 13c. Because the at least one groove 14a (e.g. one single groove or two grooves separated by a wall 14c) extends downwards beyond the bottom edge 14a of the wall 14b and into the upper, thinned portion of the stem 15, the redirected flow of the initial volume indeed traverses the sample outlet 13c and continuous flowing downwards along the outer surface of the stem 15. This is facilitated by the smooth beveled transition segment 14d of the stem 15, which avoids that the redirected flow of the initial volume is projected back into the valve casing 13 if the transaction to the lower, wider portion of the stem 15 was too abrupt. In consequence, also a reaction force encumbering the swift lifting of the valve structure 17 to the diverting position to ensure a small sample volume is significantly reduced. Moreover, the slanted wall 14b also contributes to the redirection of the flow of the initial volume towards the base of the valve casing 13, where the redirected flow can still be drained through the sample outlet 13c owing to the thinned portion of the stem 15, e.g. the thinned cross-sectional area of the upper portion of the stem, between the transition segment 14d and the bottom edge 14e of the wall 14b, compared to the wider cross-sectional area of the lower portion of the stem 15 (as seen in planar view, perpendicular to the z-axis). A further advantage of the slanted wall 14b is given by the fact that the received initial volume of the liquid flow is exerting a (dynamic) pressure force on the wall 15b that is decomposed into a force component parallel to the flow direction and a force component parallel to the z-axis, e.g. the slanted wall 14b can be used to further enhance an upwards directed lifting force, in addition to the buoyancy force through the lifting member 15a, which is driving the valve structure 17 from the sampling position to the diverting position. This secondary lifting force by the slanted wall 14b is much appreciated in cases of small sampled initial volumes, e.g. about 4 ml of first-void urine, for which a volume of the lifting member that is submerged in the already sampled and collected liquid is typically small, hence achieving only small buoyancy forces, as volumes of collecting receptacles cannot be made arbitrarily small. Receptacles of too small volume will otherwise render capillary adhesion forces decisive and the initial volume is not removed quickly enough to prevent contamination thereof by the subsequent volume, e.g. contamination of an earlier fraction of the first-void urine by a later fraction of first-void or mid-stream urine.
Preferably, a tubular sampling connector 13e extends downwards from a lower side of the base of the valve casing 13, at least partially circumferentially enclosing the opening of the sample outlet 13c. A receptacle for collecting the initial volume of the sampled liquid flow, may be removably connectable to said sampling connector 13e, e.g. via a snap-fit or screw-fit connection. Gravitational acceleration forces assist in draining the initial volume through the sample outlet 13c, along the outer surface of the stem 15, and towards the receptacle that is connected to the sampling device 10 prior to use. It is advantageous to provide the sampling connector 13e with a recess over a portion of its circumference to obtain a sampling connector with a baffle-type end portion since this further assists and accelerates the draining process of the initial volume from the lower end of the groove 14a over the beveled transition segment 14d towards the outer surface of the lower portion of the stem 15, whereby the risk of sticking and congestion by accumulation of the drained liquid is reduced.
During use of the device 10, the liquid flow pertaining to the initial volume is sampled through the sample outlet 13c and generates a liquid column in a receptacle that has been previously connected to the device 10, e.g. to the sampling connector 13e. Preferably, the shape and depth of the receptacle is selected to cooperate with the lifting member 15a in that the formation of the liquid column in the receptacle is accompanied by a quickly progressing immersion of the lifting member 15a. The lifting member 15a may be provided as an air-filled cavity that is arranged in the hollow interior of the lower portion of the stem 15. This has the additional advantage that material weight and cost related to the formation of the elongated stem 15 is conveniently saved by provision of the cheap, low density fluid air. This also allows connectable receptacles of smaller diameter to be used to efficiently increase the immersed volume of the lifting member 15a, hence to increase the buoyancy force. Nevertheless, embodiments of the invention are not limited thereto and other floating structures and/or materials may be used instead of, or in addition to, air cavities in the lower portion of the stem 15, for instance a block of foams into which the lower end portion of the stem extends. As a consequence of the buoyancy force acting on the lifting member 15a as a floater, the valve structure 17 as a whole is lifted and forced upwards as the height of the sampled liquid column continues raising. The buoyancy-driven vertical displacement is stopped, and a further elevation of the valve structure 17 prevented, as soon as the diverting position is adopted.
In the diverting position, the upper side of the cap 16 is pushed up against a resilient stopper 13d, a projection protruding from the inner surface of the valve casing 13, e.g. a small flexible pin or stud extending inwards into the valve casing bore. The cap 16 is provided as a asymmetrically shaped disk, e.g. an originally circular disk of which a segment has been removed along a chord, which is most visible in the perspective view of
The outlet conduit 11 may be adapted for connection to a further receptacle for capturing the subsequent volume, or may be adapted for connection to a further liquid sampling device, e.g. a second sampling device in accordance with embodiments described hereinabove (and suitable outlet to inlet connectors) for sampling a fraction of the subsequent volume of the liquid flow, e.g. a fraction of the mid-stream urine.
Components of the device 10 for sampling an initial volume of a liquid flow as described hereinabove, as well as attachable accessories, may be provided separately in a kit of parts. With reference to
A variation of the preceding embodiment is now described with reference to
The following describes a best mode of operating the device for sampling an initial volume of a liquid flow according to embodiments of the invention. To detect sexually transmitted infections in urine samples, samples taken from of a first small fraction of first-void urine, e.g. the initial 4 ml thereof, are recommended; this improves the reliability of the results obtained by urinalysis. Therefore, care has to be taken to not spill or lose any of the initial volume during the process of taking samples. This should not come at the expense of less handling comfort and hygiene when using the sampling device. Prior to sampling the initial volume of the liquid, e.g. urine, the user of the sampling device is connecting the receptacle to the valve casing (e.g. by screwing, snap-fitting, push-fitting the receptacle onto a sampling connector), or, if the receptacle has been previously connected to the valve casing, may check that it is connected in a secure way, e.g. such that it cannot loosen and fall down subsequently. In cases, in which the sampling device is delivered to the user as a kit of parts, optionally including further parts such as expandable funnels, the user is prompted to assemble these parts as described hereinabove. A buffer solution or perseveration agent may be added to the bottom of the receptacle. The user then positions the distant opening 12a of the inlet conduit 12 on the urinary meatus, wherein the wide funnel-shaped opening 12a is adapted to the anatomical shape around the meatus to prevent spillage or losses during the time urine is being execrated by the user's body and received by the inlet conduit 12. At the same time, the user is positioning the distant opening 11a of the outlet conduit 11 over or into a further recipient, e.g. into a larger container or a toilet. Next the user verifies that the sampling device is oriented nearly vertically and starts the urination process. An initial volume of first-void urine to the sampling device, where it is received by the inlet 13a and directed through the sampling outlet 13c into the receptacle. While receiving the initial volume, the lifting member 15a forces the valve structure 17 upwards until the cap 16 is pushing against the stopper 13d, e.g. until the valve structure has been moved from the sampling position to the diverting position. At that moment in time, the initial volume of urine has been sampled and the sample outlet 13c is being obstructed by the lower portion of the stem 15. However, the thinner portion of the stem permits the subsequent volume of urine to flow through the passageway in the valve casing 13 towards the outlet 13b and the distant opening of the outlet conduit 11a, where it is expelled from the sampling device. Once the urination is completed and no more urine is entering the inlet conduit 12, the user loosens the receptacle with the sampled initial volume. A closing lid can be firmly screwed or snapped onto the receptacle for safe delivery of the urine sample to the laboratory charged with the urinalysis and the detection of pathogens. The user may further dispose of the sampling device, e.g. by flushing a biodegradable device in the toilet, or may wash or rinse and disinfect the sampling device for a next use (optionally replacing accessories such as funnels).
While the invention has been illustrated and described in detail in the drawings and foregoing description, such illustration and description are to be considered illustrative or exemplary and not restrictive. The foregoing description details certain embodiments of the invention. It will be appreciated, however, that no matter how detailed the foregoing appears in text, the invention may be practiced in many ways. The invention is not limited to the disclosed embodiments. Other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from a study of the drawings, the disclosure and the appended claims. In the claims, the word “comprising” does not exclude other elements or steps, and the indefinite article “a” or “an” does not exclude a plurality. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage. Any reference signs in the claims should not be construed as limiting the scope.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2020/078023 | 10/7/2020 | WO |
| Number | Date | Country | |
|---|---|---|---|
| 62911817 | Oct 2019 | US |
