1. Field of the Invention
Embodiments relate to the field of sample separation for medical and biological diagnosis.
2. Background of the Related Art
Mixing, physical and/or chemical reactions and separation are basic method steps in biological research and diagnosis. In research in particular, there is a need for problem-specific laboratory systems, but these are not commercially available because of small batch sizes and because of the specific problem involved. In the absence of these systems, existing vessels, filters, centrifuges, etc., have to be improvised in order to solve the problem.
In practice, when processing small batches of samples, it has also hitherto been necessary to perform several successive work steps involving decanting, pipetting, filtering, centrifuging, etc., of the samples, which requires the samples to be successively transferred by hand between different vessels and which, in addition to the extensive labour involved, also requires a high level of output in terms of equipment, since only some of the work steps are generally carried out in each vessel. In addition to the “human” factor, the various laboratory set-ups found in different laboratories (particularly as regards vessels, pipettes, filters, etc.) also often mean that, when following the same operating instructions, different results are obtained in the individual laboratories, such that complicated optimisation procedures are then required for the reproducibility and/or standardisation of the results in the individual laboratories.
The aim of the invention is therefore to make available a system of functional units that can in each case be combined, preferably plugged together, depending on the methodological problem, and that permit simple and reproducible mixing, physical and/or chemical reactions and separation of sample media.
Surprisingly, a modular system (hereinafter also called “system” or “system according to the invention”) consisting of one or more mixing cylinders, one or more separating devices and a flow-regulating connection unit, which are combined with one another in a manner specific to the application in order to meet a wide variety of requirements, has proven itself as a particularly simple and reproducible system for the processing of sample media.
All of the features set out in the above description and in the attached claims and figures can be used both singly and also in any desired combination to implement the invention in the various embodiments thereof.
The invention accordingly relates to a system of freely combinable functional units, which system is suitable in particular for mixing, processing and/or separating samples and consists of
The functional units according to the invention therefore preferably consist of or are
The system permits the use of different cylindrical containers (closed at one end), for example test tubes. This is achieved by scaling of the dimensions. The cylindrical containers can be used as collecting or receiving vessels for the supernatants or the respective fractions.
An important criterion proves to be the configuration of the transitions between the preferably plugged-together functional units. This connection is preferably achieved by a wedge-shaped geometry. In order to ensure that sample material is not drawn by capillary forces into the sealing space between the functional units, at least one seal, in particular a linear seal, preferably (made of) propylene, is used. A number of variants are possible for the sealing (see, for example,
Spacers (32) preferably ensure that, during the backwash procedure, the separating device (3) does not come into contact with the wall of the receiving container (7), which is preferably formed as a test tube.
The individual constituents or functional units of the modular system according to the invention are explained in more detail below.
1. Mixing Cylinder
The mixing cylinder is preferably open at both ends, although it can also be open just at one end (such that the sample material would be tipped out onto the separating device), and is closed at one end by a lid, which preferably has a film hinge, or by a lid designed as a screw-on lid, stopper or plug-on cap, and is closed at the other end by a tear-off and/or pierceable foil and/or a by base cap that can be plugged on, inserted like a stopper or screwed on.
The mixing cylinder is used to receive the sample and can be used as an alternative to test tubes open at one end. The interior is designed such that it can serve simultaneously as a mixing vessel for obtaining biological, chemical or physical reactions. The geometry of the mixing cylinder ensures
Preferred features for meeting the requirements are:
Both ends of the mixing cylinder have a different geometry:
Both ends of the mixing cylinder are preferably of the same design:
Each end can be used as filling and/or emptying end, the filling and/or emptying end being designed with a lid, in particular with one of the abovementioned lids, e.g. with a removable lid. The direction of combination with a separating device can be chosen freely. Each of the ends can be connected to the separating device.
2. Separating Device
The separating devices are based on the filtering principle. The filter material and the pore size are provided in accordance with the problem to be solved. It can serve both for separation by size and also for the immobilisation of substances. Since the separating devices themselves serve as vessels, they can also serve as reaction space for chemical reactions (e.g. activation and/or coupling of proteins) and also receive substances with selective properties (e.g. with defined affinities).
3. Flow-Regulating Connection Unit (Adapter), which is Preferably Formed as a Vacuum Unit.
Vacuum unit within the meaning of the invention is understood in particular as a transition piece with (laterally arranged) suction connector, preferably for connection to a vacuum pump, such that a suction bottle is produced by connecting the vacuum unit (5) to the separating vessel (7), for example by placing or screwing/clamping the vacuum unit (5) onto the separating vessel (7).
The flow-regulating connection unit permits the connection of the separating device to different cylindrical containers (closed at one end), for example test tubes, and serves as adapter. The shape is accordingly adapted at one end to the geometry of the separating device and at the opposite end to the geometry of the respective cylindrical containers. The connection unit is responsible for a defined flow of liquid and supports the separating unit in the use of at least one separating device, preferably more than two separating devices. By closing the connection unit, it is possible for liquid for incubation purposes (e.g. for immunochemical reactions) to be kept in the separating device. After the closure of the connection unit is opened, the liquid flows into the cylindrical container. Depending on the problem to be solved, the target substance can either be located in the through-flow, immobilised on the membrane or on solid supports that have been introduced into the reaction space of the separating device.
The connection unit can be connected to the collecting and/or waste vessel either by a thread or by a wedge construction.
Experience shows that test tubes differ greatly in thread pitch depending on the manufacturer, but the internal diameter of the test tubes varies only by a few micrometers. This can preferably be compensated by a simple wedge construction of the vacuum unit. The fixing takes place preferably as an “interference fit”. This results in a system that gives the user the possibility of using existing test tubes.
The connection unit permits the combination with a vacuum filtration by attachment of underpressure-generating devices and device combinations (for example disposable syringes, hose pump, vacuum pump, water jet pump, pipette with hose, and many other devices that can generate underpressure, vacuum).
The principle of vacuum filtration shown in
The vacuum unit was constructed such that a movement of liquid takes place exclusively via the movement of the disposable syringe (57). Since the system is closed, no liquid can run from the mixing cylinder (2) via the separating unit (3) into the receiving vessel (7). The used membrane material serves as additional barrier and prevents the exchange of air from the receiving vessel by the liquid in the recipient. When the syringe is drawn up, an underpressure forms in the receiving vessel and conveys the liquid from the recipient through the separating membrane into the receiving vessel. The two nonreturn valves (56) allow the air to be displaced from the syringe without air being forced back into the separating units.
Other advantageous features and configurations of the system according to the invention will also become clear from the figures, which show various embodiments of the modular system and of the functional units of the latter.
The system of freely combinable functional units according to the invention consisting of
The system is preferably formed, in particular in terms of the dimensions of its functional units, such that it can be applied or connected to commercially available receptacles, in particular laboratory tubes, preferably with a volume of 5-100 ml, preferably a filling volume of 15 ml or 50 ml.
In a preferred embodiment, the system according to the invention is characterised in that the mixing cylinder (2) can be temporarily closed at both ends from both sides.
In another preferred embodiment of the system, the interior of the mixing cylinder(s) is designed such that an optimal and thorough mixing of the samples is permitted.
In another advantageous embodiment of the invention, the system is designed such that the one or more separating devices are based on the filtering principle, i.e. in particular that the one or more separating devices each have a filter, a membrane and/or a sieve or are designed with these. The filters, membranes and/or sieves preferably have pores with a pore diameter of between 10 nm and 1 mm.
In another preferred embodiment, the at least one separating device is designed such that, for substance separation, membranes can be used that have a pore diameter of between 10 nm and 1 mm.
In a particularly preferred embodiment of the system according to the invention, the one or more membranes are made of one more materials known per se and can be used both as size filters and/or also as solid supports with an immobilising surface configuration.
In another particularly preferred embodiment, the system according to the invention is characterised in that the at least one separating device can be used as reaction vessel for chemical and/or physical reactions.
Another advantageous embodiment concerns a system according to the invention in which the at least one separating device can be provided if necessary with openings for charging or emptying.
Another advantageous embodiment concerns a system according to the invention in which a flow-regulating connection unit with three-way tap forms the closure of the sample-processing system.
In a particularly advantageous development of the system according to the invention, the dwell time/transit time of the sample in/through the functional units can be freely regulated by the flow-regulating connection unit.
Another advantageous embodiment of the system according to the invention is characterised in that it can be connected to commercially available vessels for receiving the through-flow.
A system according to the invention is particularly preferred that consists of
In particular, a system according to the invention is preferred in which the at least one mixing cylinder (2) has at least one of the features 20-29 and/or 80-86 or preferably a combination of such features or particularly preferably all the features 20-29 and/or 80-86 according to the list of reference signs and/or the figures.
Another preferred system according to the invention is characterised in that the at least one separating device (3) has at least one of the features 30-42 or preferably a combination of such features or particularly preferably all the features 30-42 according to the list of reference signs and/or the figures.
Another preferred system according to the invention is characterised in that the flow-regulating connection unit (5), which is preferably formed as a vacuum unit (5), has at least one of the features 50-60 or preferably a combination of such features or particularly preferably all the features 50-60 according to the list of reference signs and/or the figures.
Another preferred embodiment concerns a system according to the invention, in particular suitable as a separating device, which also has (as a further functional unit) a collecting and/or receiving container (7), which is preferably connected to the flow-regulating connection unit (preferably vacuum unit) (5).
Another advantageous development of the invention concerns a system, in particular designed as a separating unit, which is designed according to
Another aspect of the invention relates to the use of the system according to the invention for application in biological and/or medical research, for diagnosis and/or for product control in biotechnology, in particular for mixing, processing and/or separating samples.
Other advantageous properties and features of the invention will also become clear from the following non-limiting illustrative embodiments.
Isolation of specific cells from a blood sample, explained using the example of separating CD3-positive cells from whole blood with subsequent
A mixing cylinder, a separating device, a flow-regulating connection unit and two receiving containers are needed for this application.
Whole blood to which anticoagulants have been added is introduced with anti-CD3 particles into the mixing cylinder at the filling end. The mixing cylinder is closed and is rotated on a roller mixer for at least 10 minutes and at most 45 minutes. After the incubation, the mixing cylinder is opened at the emptying end. The separating device with a receiving container is then applied to the cylinder. The assembly of mixing cylinder, separating device and receiving vessel is turned. The mixing cylinder is then opened at the filling end. The mixture of whole blood and anti-CD3 particles then runs through the separating device. The particles that have captured the CD3-positive cells from the whole blood remain on the membrane of the separating device. Unbound and undesired cells are flushed into the receiving vessel by repeated flushing with a wash solution.
Cascade application for simultaneous isolation of different specific fractions from a blood sample, explained using the example of separating CD4-positive and CD8-positive cells from whole blood, as rapid test for determining HIV immune status.
A mixing cylinder, two separating devices, two flow-regulating connection units and at least three receiving containers are needed for this application.
Two different particle sizes are needed in accordance with this application:
In accordance with the two particle sizes, two separating devices with different pore sizes are needed:
Whole blood to which anticoagulants have been added is introduced with the small anti-CD4 particles and the large anti-CD8 particles into the mixing cylinder at the filling end. The mixing cylinder is closed and is rotated on a roller mixer for at least 10 minutes and at most 45 minutes. After the incubation, the mixing cylinder is opened at the emptying end. The separating device with the large pore size is then applied first to the cylinder, and then the separating device with the small pore size. Lastly, the receiving container is positioned on the last separating device. The assembly of mixing cylinder, separating devices and receiving container is then turned and the mixing cylinder is opened at the filling end. The large CD8 particles together with the cells remain on the membrane of the first separating device, the smaller CD4 particles pass through the first separating device and remain on the lower separating device, and undesired and also unbound cells pass through the separating devices and are collected in the receiving vessel. Each of the separating devices together with the particle/cell complexes can then be used as an independent fraction. To determine the HIV immune status, a ratio of the isolated CD4-positive cells to CD8-positive cells is formed. Points (A)-(D) from application example one can likewise be applied for each of the fractions.
Cascade application for simultaneous isolation of different cytokines for the specific determination of the inflammation status from a blood sample.
A mixing cylinder, three separating devices, three flow-regulating connection units and at least four receiving containers are needed for this application.
Three different particle sizes are needed in accordance with this application:
In accordance with the three particle sizes, three separating devices with different pore sizes are needed:
The isolation of the specific cytokines takes place in the manner explained in application examples one and two. Each of the separated fractions is then incubated with chemicals on the corresponding separating unit in such a way that the loading of the particles with the respective protein can be detected by a colour change. The intensity of the colour change in the reaction charge can be determined with the aid of a simple measuring device. With the measurement values obtained, a corresponding diagnosis can then be made regarding the inflammation status.
Number | Date | Country | Kind |
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10 2008 050 750.4 | Oct 2008 | DE | national |
This application is the United States national phase under 35 U.S.C. §371 of PCT International Patent Application No. PCT/DE2009/001411, filed on Oct. 6, 2009, and claiming priority to German Application No. 10 2008 050 750.4, filed on Oct. 6, 2008.
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/DE09/01411 | 10/6/2009 | WO | 00 | 8/10/2011 |