MXPA97009820A - Equipment and method for the flui collection - Google Patents

Abstract

A fluid collection, filtration and storage device is described. The device has a first tube with a first end closed, a second end open, surfaces of the wall of the inner tube and an internal diameter, a second tube with a first end porously closed by a filter and a second end open and having a external diameter smaller than the inner diameter of the first tube, the second tube further makes sliding contact with the inner tube wall surfaces of the first tube at the first end of the second tube when the second tube is inserted into the first tube and a cap adapted to seal the second open end of the first tube and the second open end of the second tube in a single closing operation while the second tube is inserted in the first tube. The equipment is particularly adapted to collect and store biological, viscous samples, such as saliva, in the inner tube after the sample has been mixed with a preservative or other substance initially in the filt.

Description

EQUIPMENT AND METHOD FOR THE COLLECTION OF FLUIDS FIELD OF THE INVENTION This invention is in the field of fluid collection equipment and in a preferred embodiment is particularly directed to equipment used to collect and store viscous fluids while protecting fluids against bacteriological contamination.

BACKGROUND OF THE INVENTION The collection and storage of viscous biological samples, such as saliva, that are subject to degradation - by bacteria and other organisms, is a common problem. Viscous liquids are difficult to handle in pipettes and other devices normally used with less viscous aqueous samples. The viscosity of the samples also makes it difficult to mix the samples with preservatives in order to protect them against biological decomposition. Such preservatives (or other materials, such as inhibitors of endogenous peptides or other enzymes present in the sample of REF .: 26472 • -___. 4P biological origin), which are often dried on the surfaces of a container in which a non-viscous aqueous solution will be collected, they can not spread throughout a viscous material and therefore do not protect the inner portions of the liquid against the action bacterial A number of systems have been developed to handle viscous liquids, particularly saliva and blood serum. See for example, Haldopoulos, U.S. Patent No. 3,832,141; Ohringer, U.S. Patent No. 3,846,077; Breno, U.S. Patent No. 4,209,488; Mar, U.S. Patent No. 4,644,807; Romer, US Patent No. 15 4,895,808; and Seymour, U.S. Patent No. 5,268,148. However, those devices that have been previously developed in this field are generally sophisticated devices proposed for use by expert laboratory technicians. The The present invention was made with an inexperienced user in mind, particularly an untrained patient who collects a saliva sample or a similar fluid sample at home or in the absence of any training or instruction other than that of the patient. the written instructions that will accompany the team. This is necessary for simplified and easy-to-use collection equipment for the collection and storage of viscous fluids, such as saliva, which has led to the present invention.

BRIEF DESCRIPTION OF THE INVENTION It is an object of the present invention provide equipment that allows the simple collection and storage of viscous biological fluids, such as saliva, as well as other viscous fluids. It is a further object of the invention to provide a collection system in the which a viscous fluid can be completely mixed with a preservative in order to avoid degradation by microorganism, such as bacteria, which may be present in the sample. These and other objectives of this The invention has been achieved by providing a fluid collection, filtration and storage device, comprising a first tube having a closed first end, a second open end, surfaces of the tube wall. interiors and an internal diameter; and a second tube having a first end porously closed by a filter and a second open end and having an outer diameter smaller than the internal diameter of the first tube, the second tube also slidably contacts the surfaces of the wall of the inner tube of the first tube to at least the first end of the second tube when the second tube is inserted in the first tube; and a cap adapted to seal the second open end of the first tube and the second open end of the second tube in a simple closing operation while the second tube is inserted into the first tube. The equipment is particularly adapted for the collection and storage of viscous biological samples, such as saliva, in the inner tube after the sample has been mixed with a preservative or other substance located in the filter, such as a dye or protease inhibitor. .

BRIEF DESCRIPTION OF THE DRAWINGS The invention will be improvement understood by reference to the following description of the specific embodiments in combination with the drawings forming part of the specification, wherein: Figure 1 is a perspective view of a fluid filtration and storage tube, which is part of the apparatus of the invention. In this Figure, line 2.-2. shows the plane of view in Figure 2.

"Figure 2 is a plan view of a first embodiment of the interior collection tube of the apparatus of the invention.

Figure 3 is a plan view of a second embodiment of the interior collection tube showing the same view presented in Figure 2.

Figure 4 is a plan view of a fluid collection tube, exterior of an embodiment of the invention.

Figure 5 is a perspective drawing showing the interaction of the inner tube and the outer tube when the fluid is being transferred from the outer collection tube to the inner collection tube.

Figure 6 is a plan view of a first embodiment of the invention showing a lid that seals both the inner and outer tubes of an embodiment of the invention.

Figure 7 is a plan view of a second embodiment showing a second cap that seals the collection tubes both inside and outside.

Figure 8 is a perspective view of a fluid collection equipment.

DESCRIPTION OF THE SPECIFIC MODALITIES Referring now to the embodiments shown in the drawings for the purpose of illustrating the present invention, the same numbers are used to show the corresponding elements of the different embodiments in the different drawings.

The apparatus of the invention comprises two tubes that fit one inside the other. The inner tube 10, referred to for the filtration and storage tube, is shown in Figure 1 in a perspective view. Although this embodiment is shown as a tube having a circular cross section, the cross section may be in any shape since the inside had fit within the outer tube described later. The inner tube has two ends, an open end 12 and a porous closed end 14. By "porously closed" it is implied that a porous material is present at the end 14 of the tube 10 so that a liquid can penetrate through. of the pores of the porous material, which will act both as a filter and as a mechanical means to divide or separate the polymeric materials that may be contributing to the viscosity, such as mucopolysaccharides in the saliva. On the other hand, the "porous closed" end blocks the passage of solids, including particulate solids larger in size than pores. A detail of the porous closure is shown in Figure 2. In this first embodiment, the collection and storage tube 10 is formed of a simple plastic or glass tube 11, an annular elastomeric plug 13 and a porous passage defined by an opening external 17, a porous plug 18 trapped in the annular elastomeric plug 13 and an internal passageway 19. In this embodiment, the elastomeric plug 13 has an edge or lip 15 that contacts the inner surfaces of the outer collection tube (to be described in connection with Figure 4). Figure 3 shows an alternative embodiment of the same view shown in Figure 2. In this embodiment all portions of the collection and storage tube 10 formed in Figure 2 by the tube 11 and the elastomeric plug 13 are formed as a device unit, as they can be produced from molded plastic. The porous plug 18 is then inserted into the passage to provide the porous closure described above. Alternatively, the central portion of the porous end of the collection and storage tube 10 can be formed of the same material as the walls as in an integral filter (for example, when injecting air or inert liquids in this region during the molding process).

Ff Figure 4 shows an embodiment of the outer tube 20, referred to as a sample collection tube. This tube has an open end 22 and a permanently closed end 24. In the preferred embodiments a volume marker can be inscribed or otherwise marked on the outer side of the container, as shown in 26 of Figure 4. Figure 5 shows the two tubes of the appliance in use. A sample 21 has been collected in the outer tube 20. The inner tube 10 is being forced by the pressure of the hand inside the outer tube 20, which forces the sample 21 through the porous filter and into the interior of the tube inside 10. In the preferred embodiments of the invention, the outer bottom of the inner tube 10 is formed to make light contact with the inner bottom of the outer tube 20 so that the space 38 between the two tubes is at a minimum when the inner tube 10 has been forced to the bottom of the outer tube 20. The space 38 is generally less than 20 μl, preferably less than 10 μl and more preferably less than 5 μl. This provides maximum fluid transfer within the storage portion of the inner tube 10. As shown in Figure 6, the lid 30 closes both the inner tube 10 and the outer tube 5 20 in a single closing operation. In this embodiment, a forced fit is provided by an inner plug 34 that fits within the open end of the inner tube 10 and an annular ring 32 that fits between the inner and outer tubes.

The forced fit is preferably narrow for the outer tube and loose for the inner tube so that the two tubes do not separate from each other during the removal of the cover 30. An alternative mode of The lid and storage system is shown in Figure 7. In this embodiment, the inner tube 10 is somewhat larger than the outer tube 20 and the internal plug 34 projects somewhat from the bottom of the lid 30, which allows which the lid is inserted first inside the inner tube to facilitate handling. The annular ring 32 operates in the same manner, but the cover is secured to the outer tube 20 by a screw type closure 36 with mating or mating threads in the cover 30 and outer tube 20. As before, the inner tube # is held in place by a forced, loose fit. For those skilled in the art, similar variations in the structure of the lid in the 5-container technology will be apparent from these examples. Filtration systems similar to a piston similar to that shown in Figure 5 exist in the prior art, but not in a permanent collection and storage system, For example, U.S. Patent No. 3,832,141, which is incorporated herein by reference, shows an inner filter tube and an outer collection tube similar in some manner to the apparatus of the invention. However, the device is not designed to collect and store samples and is actually designed specifically so that the outer and inner tubes can be separated from each other after the sample is collected in the inner tube. A similar system is also shows in Figures 23-26 of U.S. Patent No. 5,268,148. Again, the system is not designed for the storage of samples and also contains a blotting paper for the saliva located in the exterior tube that exemplifies many of the disadvantages of the prior art. Of * fact, most if not all of the devices of the prior art show a porous blotting paper of some kind that is used to collect the saliva samples. While such pads can easily be used to collect saliva by inserting the pad into a patient's mouth, it is impossible to accurately measure the amount of fluid that is collected in such a porous material. By For example, a patient with a dry mouth could only wet a porous pad poorly, whereas a patient with normal saliva flow could provide two or more times as much saliva on the equally sized pad. In In contrast, the simple outer collection tube 20 of the invention, with an optional marking 26 showing the desired volume of the sample, allows a known volume of saliva to be collected. By providing a collection tube 10 and filtering similar to a piston, which fits tightly into the collection vial, all or almost the entire sample can be forced through the porous filter to the end of the collection tube 10 and into the inner collection tube, where the sample will remain as shown in Figures 6 and 7.

Since this sample has been forced through the porous plug (filter) 18, the apparatus of the present invention provides complete mixing of the sample with any soluble material located on the filter 18 that could be desired to be mixed with the sample. For example, a preservative may be included in the filter to protect the biological fluids against degradation. While prior collection devices for non-viscous fluids have provided a soluble material coated on the walls of a collection container, such a system would not be suitable for viscous fluids, such as those proposed to make the samples used in the devices of the invention. Diffusion occurs only slowly in viscous samples, and a conservator or other material coated on the walls of a collection vial would not easily penetrate all portions of a sample. This is particularly true in saliva, which contains mucopolysaccharides and glycoproteins that prevent diffusion. These materials also coagulate sometimes within fabric-like structures that further impede diffusion. By forcing saliva or a similar fluid through a porous disc or filter as described above, not only the saliva will be well mixed with the preservative or other chemical agent located in the dry form in the filter, but the mucopolysaccharides and the glycoproteins they will be divided or separated to provide a less viscous fluid when saliva is present in the inner collection tube. The filter or porous plug used in the apparatus of the invention can be selected by the particular viscosity and type of the sample that is collected. The variety of pore sizes and void volumes that can be used can be seen when considering saliva as an example. Pore sizes less than 1 miera have been shown to work, while pores of 100 micras also appear to be useful, although close to the limit for dividing or separating the mucopolysaccharides and glycoproteins as described above. Pore sizes in the 25-50 micron range are preferred to avoid coagulation or clogging that sometimes occurs with smaller pore sizes. However, a two-part filter with an ordinary external filter over an internal filter of one mine would work satisfactorily, as the ordinary external filter would prevent coagulation or obstruction of the finer internal filter. The closure of the adjustment with which the inner tube makes contact with the outer tube will vary depending on the fluid viscosity and the ordinaryness of the filter. The main feature of the adjustment required for a good operation is that the filter is sufficiently porous to provide less fluid resistance for the desired sample collected in the outer tube than the fluid resistance that occurs in the locations where two tubes contact each other . Elastomeric materials are preferred for sliding contact, since these do not require strict manufacturing tolerances. Nevertheless, if manufacturing tolerances are high, even rigid materials can be used to provide sliding contact. Although the above examples show tubes with circular cross-sections and corresponding, pint-shaped structures of circular shapes, other shapes are possible since the inner tube or some portion thereof such as the elastomeric plug shown in Figure 2 makes contact in a manner slidable with the inner surfaces of the outer tube in all locations so that the sample is forced through the porous filter and around the edges of the inner tube where the inner tube makes contact with the inner walls of the outer tube does not escape. Any number of materials can be present in the filter so that they will mix10 with the sample, depending on the particular sample that is collected. For biological samples, this generally includes a conservator. Examples of preservatives include sodium azide (NaN3) and a combination of 5-chloro-2-methyl-4-isothiazolin-3-one and 2-Methyl-isothiazolin-3-one (PROCLON ™). A particularly preferred preservative for saliva is a mercuric, organic, crystalline antiseptic. The general operating characteristics of the preservatives are those that are soluble in the The fluid with which they must be mixed and stable enough for storage under conditions under which the collection equipment will be used. Since these conditions will vary with the sample and with the way in which the sample is collected, a variety of agents can be used. For example, a collection kit designed for use in the home can be refrigerated, which will provide relatively appreciable storage conditions and allow reasonably sensitive preservatives to be used. A test equipment designed for field operation can be subjected to a variety of different temperatures and humidity and thus would restrict the preservatives used in a device of this class. Other materials that may be present in the filter include a dye, which makes it possible to easily determine whether uniform mixing has taken place. Examples of dyes include any of the numerous normal dyes exhibited in catalogs of normal dyes, selected to be soluble in the material that is collected. A particularly useful dye for the saliva collection is FD &C Blue # 1. The essential characteristic of the dye is that it is soluble in the liquid that is collected. The individual collection apparatus of the present invention can be stored in a fluid connection equipment comprising multiple tubes of the two types described above and multiple caps as shown in Figure 8.

The equipment will normally comprise a container 39 adapted to hold the tubes and covers in an easily accessible manner (typical of the type used in a test tube rack in which the individual tubes are inserted into the holes in a device similar to a grid, typically made of cardboard in a commercial collection equipment). The individual tubes can have integral labels for easy use (for example containing spaces for the patient's name and collection date and time), and written instructions adapted so that the particular type of sample can be included in the box that holds the individual tubes. All publications and patent applications mentioned in this specification are hereby incorporated by reference to the same extent as if each publication or individual patent application is specified and individually indicated to be incorporated by reference. The invention is now fully described, it will be apparent to one of ordinary skill in the art that many changes and modifications can be made thereto without departing from the spirit and scope of the appended claims.

It is noted that in relation to this date, the best method known to the applicant to carry out the aforementioned invention, is that which is clear from the present description of the invention.

Having described the invention as above, the content of the following claims is claimed as property.

Claims (20)

1. A fluid collection, filtration and storage device, characterized in that it comprises: a first tube having a first closed end, a second open end, inner tube wall surfaces and an internal diameter, a second tube having a first end porously closed by a filter and a second open end and having an outer diameter smaller than the internal diameter of the first tube, the second tube also slidably contacts the surfaces of the inner tube wall of the first tube in the first end of the second tube when the second tube is inserted in the first tube; and a cap adapted to seal the second open end of the first tube and the second open end of the second tube in a simple closure operation while the second tube is inserted into the first tube, the device is not absorbent.

2. The device according to claim 1, characterized in that the filter is placed in a tubular seal to form an annular plug, the plug has an edge that slidably contacts the interior tube wall surfaces of the first tube when inserted into the second open end of the first tube.

3. The device according to claim 1, characterized in that the filter is integrally manufactured with the first end of the second tube.

4. The device according to claim 1, characterized in that the filter is sufficiently porous to provide less fluid resistance for a liquid located in the first tube than the fluid resistance at the location where the second tube slidably contacts the first tube. tube.

5. The device according to claim 1, characterized in that the fluid is saliva.

6. The device according to claim 1, characterized in that the filter has pores with an effective diameter of less than 100 microns.

7. The device according to claim 1, characterized in that the filter has pores with effective diameters of 1 to 50 microns.

8. The device according to claim 1, characterized in that it additionally comprises a conservator located in the filter.

9. The device according to claim 8, characterized in that the preservative is soluble in saliva.

10. The device according to claim 9, characterized in that the preservative is a mercuric, organic, crystalline antiseptic.

^ F 11. The device according to claim 1, characterized in that it additionally comprises a dye located on the filter.

12. The device according to claim 11, characterized in that the dye is soluble in saliva.

* 13. The device according to claim 10, characterized in that the dye is a blue dye.

14. The device according to claim 1, characterized in that the second The tube is substantially equal in length to the measured internal distance of the first tube from the second closed end to the second open end of the first tube.

15. The device according to claim 1, characterized in that the cover further comprises screw threads and the first tube further comprises screw threads on the open end of the first tube that engages the threads 25 screw cap.

16. The device according to claim 1, characterized in that the lid closes the first and the second tubes with a 'friction fit.

17. The device according to claim 1, characterized in that the inner surface of the cover comprises an annular projection • at its lower end that fits between the 10 open end of the first tube and the open end of the second tube.

18. A fluid collection device, characterized in that it comprises: first multiple tubes according to claim 1; second multiple tubes according to claim 1; multiple layers according to claim 1; and a container adapted to hold the first and second tubes and lids.

19. A method of collecting and storing a fluid, characterized in that it comprises: collecting the fluid in a first tube having a closed first end, and a second open end, inner wall surfaces of the tube and an internal diameter; insert inside the first tube a "Internal filtering and holding device that 10 comprises a second tube having a first end porously closed by a filter and a second open end and having an outer diameter smaller than the internal diameter of the first tube, the second tube also makes contact with 15 slidable with the wall surface of the tube, inside the first tube at the first end of the second tube when the second tube is inserted into the first tube, whereby the fluid collected in the first tube is forced through the tube. 20 filter inside the second tube; and sealing the first tube and the second tube with a cap adapted to seal the second open end of the first tube and the second open end of the second tube in a simple closing operation. 25

20. A method according to claim 19, characterized in that the fluid is collected in the first tube at a predetermined volume mark in the tube.