DE102016213060A1 - Vessel for laboratory use - Google Patents

Abstract

The invention relates to vessels made of plastic with a conically shaped interior of the improved mixing and crushing of particular biological samples. The invention further relates to the use of the vessels for mixing or comminuting laboratory samples. In a further aspect, the invention relates to a method and kit for digesting biological material using the vessels of the invention in combination with grinding media.

Description

Field of the invention

The invention relates to vessels with a conically shaped interior for improved mixing and comminution of particular biological samples. The invention further relates to the use of the vessels for mixing or comminuting laboratory samples. In a further aspect, the invention relates to a method and kit for digesting biological material using the vessels of the invention in combination with grinding media.

Background of the invention

The use of plastic closable containers is well known in the art. These vessels have found their way into laboratory work in a broad form and are essential for all sample-based laboratory work, especially in the biological, biochemical or chemical field. As lightweight, transparent and durable disposable containers, they not only allow samples to be stored, but also process samples in a variety of applications, such as polymerase chain reaction, incubation, mixing of samples, and especially digestion of biological samples. Sample digestion is the breaking up of cellular material with the release of cell components such as proteins, DNA or RNA (also called "disruption" and "homogenizing" in the biological material). Various techniques have been established for sample digestion. Thus, the sample can be homogenized by introducing an ultrasonic rod (so-called "Sonifier"). This method presents a risk of contamination in multiple samples and is not suitable for the digestion of harder material (such as plant parts or bone tissue). In an alternative method, the sample is comminuted together with grinding media such as metal, glass or ceramic balls by shaking or rotary mixing. By selecting the suitable grinding media, the most varied materials can be digested in a suitable manner in terms of their type and quantity, and also the rotary mixers customary in the laboratory (so-called "vortexers") can be used. However, the yield is still not optimal here, with an extension of the shaking period is not effective, since it is associated with a degradation of the biological material by excessive shear forces or elevated temperatures.

The EP1792657A1 relates to a lidded container made of elastic plastic for laboratory use and teaches in 1 a vessel with a conical region 3 which accounts for about 50% of the length of the vessel and is therefore not suitable for the generation of turbulent flows in the vessel.

The GB 2432 667 A relates to an apparatus and method for isolating material from biological samples. She reveals this in 2 a sample block having vessels 7 with an oblong, ie non-circular cross-section and therefore is not suitable for use in conventional laboratory equipment.

The DE 690 273 A relates to a crushing device filled with impactors and teaches a consistently box-shaped device (s. or ) or a circular device (s. and ). It is of the shape and size is not suitable for use as a laboratory vessel.

The US 2,847,169 A refers to grinding media for ball mills and discloses here in 2 a ball mill with a non-circular tube cross-section. In the 2 In the working position shown ball mill (see arrow and transported pebbles) is a drum with two side openings, namely 1 and 2 (s. 1 ) and is therefore not suitable for laboratory use, since in the field of sample preparation usually vessels with only one opening (which is then provided on top) are used.

There is therefore a need for improved possibilities for processing laboratory samples and in particular biological samples.

Summary of the invention

It is an object of the present invention to provide an improved vessel for the treatment of laboratory samples.

According to the invention the object is achieved by a vessel according to claim 1. Specific embodiments of the invention are the subject of the additional dependent or independent claims.

In a first aspect, the invention provides a vessel for mechanical digestion of biological samples comprising a tubular vessel having a vessel bottom at the bottom and a vessel opening at the top, the interior of the tubular vessel having a conical shape which is more than 70% of the length of the vessel and is designed so that the biological sample contained in the vessel is placed on a movement substantially parallel to the longitudinal axis of the vessel in a turbulent flow.

The vessel according to the invention has numerous advantages over the vessels known from the prior art.

As the inventor has found, the vessel according to the invention allows a better mixing of samples and in particular an improved digestion of biological samples.

Due to the conical region of the vessel, when the sample is shaken and, in particular, during the predominantly used movement of the vessel parallel to the longitudinal axis, a turbulent flow is generated which leads to a more effective mixing of the sample.

The conical region allows the kinetic energy normally used to form a laminar flow to be utilized in a movement of the vessel substantially parallel to the longitudinal axis in order to increase the interaction of the sample constituents by means of the chaotic fluid movement or particle movement.

This is particularly important in the sample digestion of decisive advantage, since the grinding media bounce parallel to its longitudinal axis in a chaotic manner from the Gefäßwenden through the conical configuration of the vessel interior and a shaking of the vessel, are thrown through the vessel volume and so by increased clash and thus increased shear enable particularly fast and efficient digestion of the samples.

As a result, the composition according to the invention allows accelerated sample digestion without impairing the analyte quality. As the inventors have been able to show further, a digestion of biological samples with the vessel according to the invention leads to an increased yield of high-quality DNA and RNA.

By a preferred embodiment of the vessel with an upper circular area, these vessels can also be used in conjunction with the usual laboratory equipment, such as vessel racks, centrifuges, water baths, thermoblocks, etc.

The vessels can be produced with the conventional plastic materials in a simple manner and thus also inexpensively. By choosing a suitable plastic material, the vessels can be tailored to the particular purpose. An injection mold (piece) should therefore be inexpensive to do.

In summary, the vessels according to the invention allow a faster and better quality processing of samples with simple and inexpensive application.

The invention in detail

Conventional vessels have an interior with a circular cross-section. If the vessel filled with liquid undergoes a rotational movement, a vortex with a central funnel-shaped depression forms. The individual sample components thus carry out a movement in the same direction within the vessel space, which reduces the collision of the sample particles or sample components with one another. (S. 1B ).

Without providing conclusive scientific proof for the advantageous effect of the vessels according to the invention, it is assumed here that the asymmetrical interior design leads to a turbulent flow and thus also favors the mixing or comminution of the sample material (see FIG. 1B ).

For the effect according to the invention more than 70% of the length of the vessel must be configured so conical that the biological sample contained in the vessel is placed in a turbulent flow at a substantially parallel to the longitudinal axis of the vessel shaking movement.

In a further embodiment, the conical region comprises more than 75%, preferably more than 80%, particularly preferably more than 85% and in particular more than 90% of the length of the vessel.

In a particularly preferred embodiment, the conical region comprises 100% of the length of the vessel.

In a preferred embodiment, the non-conical region of the vessel is designed in the form of a cylinder.

Accordingly, in the case of the predominantly used vessels with a filling volume of between 1 and 3 ml, the conical region of the vessel has a length of at least 5 mm, preferably of at least 7.5 mm and particularly preferably of at least 10 mm.

In one embodiment of the invention, the vessel has an internal and here preferably a bottom-mounted stirring, mixing or cutting device.

In an alternative embodiment of the invention, the vessel has no internal and here preferably no bottom-mounted stirring, mixing or cutting device.

In one embodiment, the tubular vessel in the upper region of the vessel opening has a circular outer cross-section. Thus, the vessel is compatible with numerous laboratory equipment, such as centrifuge inserts with circular openings and also allows easy closure of the vessel with the usually round lids.

In one embodiment, the vessel is configured to have an upper portion with a circular outer cross-section. As a result, the vessel can be used in the commonly used, oriented on round vessels laboratory equipment, such as vessel stents, centrifuges, thermoblocks and water baths.

In one embodiment of the invention, the vessel has a vessel volume of from 0.2 ml to 20 liters, preferably from 1 ml to 50 ml, and especially from 1.5 ml, 2 ml, 2.5 ml, 3 ml, 5 ml, 15 ml , 20 ml or 50 ml.

The vessel according to the invention can consist of the usual materials which can be used in the laboratory, for example glass, ceramics, metal or plastic and in this case preferably of plastic.

For the preparation of the vessel, a wide variety of plastics can be used. The skilled person will select a suitable plastic depending on the field of application and intended use. Preferably, the plastic is a polyolefin and more preferably the vessel is a plastic selected from the group consisting of polypropylene, polyethylene, polymethylpentene, polybutylene and polycarbonate.

According to one embodiment of the invention, the vessel is made of the plastic by means of injection molding.

In a further embodiment, the vessel is provided on the opening side with an internal or external thread to the closure with a screw cap. A screw cap allows a particularly strong closure, as it is particularly advantageous in the high mechanical stress of a rotary or Schüttelmischvorgangs.

In a preferred embodiment of the invention, the vessel has a lid which is connected to the vessel in the region of the vessel opening by means of a web which is preferably designed as a flat web. This embodiment offers the advantage that the closure and opening of the vessels can be carried out easily and quickly.

In a preferred embodiment, the lid-carrying vessel is provided with locking means for releasably locking the lid.

In a second aspect, the invention relates to the use of the closable inventive vessel for mixing or crushing samples, and more particularly for digesting biological cell samples, by shaking or rotational mixing, and more particularly by rapid shaking movements of the vessel parallel to its longitudinal axis.

In one embodiment, in this use, the sample is comminuted or digested in the vessel with the addition of grinding media by the shaking or rotation mixture. For this purpose, commercially available "bead mixer" devices can be used, such as, for example, vibrating mill MM400 (Retsch GmbH, Haan, Germany) or Qiagen's Mixer Mill (Qiagen, Hilden, FRG).

In a preferred embodiment, the grinding bodies are selected from the group comprising sand, silica particles, glass particles, metal particles and ceramic particles, wherein the particles are preferably spheres. In a particularly preferred manner, glass balls, ceramic balls or metal balls are used here. For optimal sample digestion, the media should be inert, break-proof and hard.

• a. Befüllen eines erfindungsgemäßen Gefäßes mit einer biologischen Probe und mit Mahlkörpern und optional mit einem Lösungsmittel;
• b. Optionales Verschließen des Gefäßes;
• c. Aufschließen der Probe durch Schütteln, Oszillieren oder Rotieren des gemäß den Schritten a und b vorbereiteten Gefäßes, bevorzugt unter Verwendung einer Schwingmühle oder eines „Bead beaters“.

In a third aspect, the invention relates to a method for digesting biological samples, comprising the following steps:

• a. Filling a vessel according to the invention with a biological sample and with grinding media and optionally with a solvent;
• b. Optional closure of the vessel;
• c. Digesting the sample by shaking, oscillating or rotating the vessel prepared according to steps a and b, preferably using a vibrating mill or a "bead beater".

The digestion process according to the invention can be carried out without a solvent, but also with such. The preferred solvents used are buffered solutions, such as PBS or other lysis or extraction buffers.

In one embodiment, the digestion process may be performed on a frozen sample. For this, the sample is preferably introduced into the vessel and cooled down in liquid nitrogen. Due to the strong cooling, even soft, water-containing biological samples become so brittle that they are very quickly and effectively comminuted by the grinding media. In addition, the cellular structures are broken by the shock freezing.

• a. Mindestens ein erfindungsgemäßes Gefäß;
• b. Mahlkörper; und
• c. Optional ein Lösungsmittel.

In a fourth aspect, the invention provides a kit for digesting biological samples comprising:

• a. At least one vessel according to the invention;
• b. grinding media; and
• c. Optionally a solvent.

These and other aspects of the invention are described in detail in the drawings and the embodiments. The pictures show:

1 shows the distribution of balls as grinding media in an aqueous (A) liquid in a vortexer rotation mixing in a circular section vessel (A) or in a vessel without liquid with 4 rounded corners (B).

2 shows in (A) is a schematic representation of a vessel according to the invention (above) and a conventional vessel (bottom) in side view (left) and in cross section (right). In (B) the cross sections of conventional vessels are shown on the left side and two exemplary cross sectional configurations of the vessels according to the invention on the right side.

3 Figure 1 shows in (A) an illustration of gel electrophoretic separation of DNA and RNA from tobacco leaves using either conventional mortar and pestle digestion of frozen samples (Samples 1 and 2: DEB12 N ₂ and Shorty N ₂ ) or digestion according to the invention (Samples 3 and 4: DEB12 ☐ and Shorty ☐) were isolated. Shorty is a quick and rapid extraction buffer modified from Edwards et al. Nucleic Acids Research. 1991, page 1349. In (B), the results of the spectrophotometric measurement of DNA samples 1 to 4 are summarized in tabular form (top) and the respective absorption curves are shown in comparison (bottom).

4 Figure 9 shows in (A) an illustration of a gel electrophoretic separation of RNA from tobacco leaves isolated either with a conventional round vessel (Samples 1 and 2: REB14 and REB15 Round) or with the digestion of the invention (Samples 3 and 4: REB14 and REB15 Square) were. In (B), the results of the spectrophotometric measurement of RNA samples 1 to 4 are summarized in tabular form (top) and the respective absorption curves are shown in comparison (bottom).

5 shows schematic representations of various inventive vessels in side view with a conical region b, which accounts for more than 70% of the length of the vessel. The following embodiments are shown from left to right: a vessel with a conical region b and a cylindrical region a, the same vessel in a threaded embodiment for receiving a screw cap, a vessel with a conical region which covers 100% of the length of the vessel and this latter vessel also in an embodiment with a thread for receiving a screw cap. In the first illustrated vessel, the longitudinal axis L is illustrated, wherein the shaking movement is carried out substantially parallel to this longitudinal axis L.

EXAMPLES

1. Purification of DNA from tobacco leaves

1.1 Question

In this experiment, the DNA isolation according to the standard digestion with liquid nitrogen and mortar / pestle is to be compared with digestion using the non-round vessels and spheres according to the invention. The material used is fresh tobacco leaves, which are a difficult substrate for DNA isolation.

1.2 Material and Methods

• • Inkubation bei 65°C für 10 Minuten
• • Zentrifugation bei 4000 Upm für 10 Minuten
• • Jeweils 1 ml des Überstandes in ein 2 ml Mikrozentrifugenröhrchen überführen
• • Zugabe an 0.6 ml CHCl₃ und sanftes Mischen für 1 Min.
• • Phasenseparation durch Zentrifugation bei 13000 Upm für 7 Minuten
• • Überführen der oberen Phase in ein neues Mikrozentrifugenröhrchen
• • Zugabe von 600 µl Isopropanol
• • Inkubation bei 4°C für 10 Minuten
• • Zentrifugation bei 13000 Upm für 15 Min.
• • Entfernen des Überstandes und Waschen des Pellets mit 70% Ethanol
• • Zentrifugation bei 13000 Upm für 7 Min.
• • Entfernen des Überstandes
• • Resuspension des Niederschlags in 100µl Wasser oder 2.5mM Tris pH 8.0
• • Inkubation bei 65°C für 10 bis 30 Minuten bei geöffnetem Gefäßdeckel
• • Auftrennen von je 4 µl in einem Agarosegel (1% Agarose, 7 Volt/cm, 45 min)
• • Spektralphotometrische Analyse eines Aliquots (1µl) (Nanodrop-Photometer)

In each case approx. 1g of tobacco leaves (fresh weight) are worked up. In a first experiment, these leaves are frozen in liquid nitrogen and hand-ground in a mortar with a pestle and then taken up in the DNA-DEB-12 or Shorty extraction buffer. The Shorty buffer contains 200mM Tris, 400mM LiCl, 25mM EDTA, 1% SDS, and adjusted to pH 9.0 with NaOH. In the second experiment of the invention, the tobacco leaves are taken up in 50 ml plastic tubes of square inner cross section, 5 ml of EB buffer and 6 × 4 mm and 3 × 10 mm steel balls and vortexed for 1-2 minutes. The tobacco leaves digested by the two methods were then subjected to DNA isolation according to the following procedure:

• • Incubate at 65 ° C for 10 minutes
• • Centrifuge at 4000 rpm for 10 minutes
• • Transfer 1 ml of the supernatant into a 2 ml microcentrifuge tube
• • Add 0.6 ml of CHCl ₃ and mix gently for 1 min.
• Phase separation by centrifugation at 13000 rpm for 7 minutes
• Transfer the upper phase to a new microcentrifuge tube
• • Add 600 μl of isopropanol
• • Incubate at 4 ° C for 10 minutes
• • Centrifugation at 13000 rpm for 15 min.
• • Remove the supernatant and wash the pellet with 70% ethanol
• • Centrifugation at 13000 rpm for 7 min.
• • Remove the supernatant
• • Resuspension of the precipitate in 100μl water or 2.5mM Tris pH 8.0
• • Incubate at 65 ° C for 10 to 30 minutes with the vial lid open
• Separate 4 μl into an agarose gel (1% agarose, 7 volts / cm, 45 min)
• Spectrophotometric analysis of an aliquot (1μl) (nanodrop photometer)

1.3 Results and discussion

The four different approaches with the leaf tissue quantities used are summarized in the following table: No. buffer Disruption method Wet weight in grams 1 DEB12 N ₂ Liquid nitrogen 1,074 2 Shorty N ₂ Liquid nitrogen 1,008 3 DEB12_SQ Square tubes, grinding balls 1.005 4 Shorty_SQ Square tubes, grinding balls 0.992

In the 3A documented gel electrophoretic analysis showed that the sample digestion with the vessels according to the invention leads to a qualitatively outstanding DNA.

The spectrophotometric analysis of the DNA samples (s. 3B ) confirmed the high quality of the DNA samples using the vessels of the invention. In addition, the method according to the invention led to an increased nucleic acid yield which was 32% and 158% higher than the nucleic acid yield achieved by the comparison method.

2. Purification of RNA from tobacco leaves

2.1 Question

In this experiment, the RNA isolation is compared with grinding balls in conventional round vessels with the use of the same grinding balls in the non-round vessels according to the invention. The material used is fresh tobacco leaves, which are a difficult substrate for RNA isolation.

2.2 Material and Methods

In both approaches ("O" = round vessels, "SQ" = vessels with square cross section) the tobacco leaves are placed in 50 ml FALCON plastic vessels with square or round internal cross section, 5 ml RNA extraction buffer (REB14 or REB15) and metal spheres (6 spheres with 4 mm diameter and 3 balls with 10mm diameter) and vortexed for 1-3 minutes.

• • Inkubation bei 65°C für 10 Minuten
• • Zentrifugation bei 4000 Upm für 10 Minuten
• • Jeweils 1 ml des Überstandes in ein 2 ml Mikrozentrifugenröhrchen überführen
• • Zugabe an 0.6 ml CHCl₃ und sanftes Mischen für 1 Min.
• • Phasenseparation durch Zentrifugation bei 13000 Upm für 7 Minuten
• • Überführen der oberen Phase in ein neues Mikrozentrifugenröhrchen
• • Zugabe von 600 µl Isopropanol
• • Inkubation bei 4°C für 10 Minuten
• • Zentrifugation bei 13000 Upm für 15 Min.
• • Entfernen des Überstandes und Waschen des Pellets mit 70% Ethanol
• • Zentrifugation bei 13000 Upm für 7 Min.
• • Entfernen des Überstandes
• • Resuspension des Niederschlags in 100µl Wasser oder 2,5 mM Tris-Puffer, pH 8,0.
• • Inkubation bei 65°C für 10 bis 30 Minuten bei geöffnetem Gefäßdeckel
• • Auftrennen von je 8 µl in einem Agarosegel (1% Agarose, 7 Volt/cm, 45 min)
• • Spektralphotometrische Analyse eines Aliquots (1µl) (Nanodrop-Photometer)

The tobacco leaves digested by the two methods were then subjected to RNA isolation according to the following procedure:

• • Incubate at 65 ° C for 10 minutes
• • Centrifuge at 4000 rpm for 10 minutes
• • Transfer 1 ml of the supernatant into a 2 ml microcentrifuge tube
• • Add 0.6 ml of CHCl ₃ and mix gently for 1 min.
• Phase separation by centrifugation at 13000 rpm for 7 minutes
• Transfer the upper phase to a new microcentrifuge tube
• • Add 600 μl of isopropanol
• • Incubate at 4 ° C for 10 minutes
• • Centrifugation at 13000 rpm for 15 min.
• • Remove the supernatant and wash the pellet with 70% ethanol
• • Centrifugation at 13000 rpm for 7 min.
• • Remove the supernatant
• Resuspension of the precipitate in 100 μl water or 2.5 mM Tris buffer, pH 8.0.
• • Incubate at 65 ° C for 10 to 30 minutes with the vial lid open
• Separate 8 μl each in an agarose gel (1% agarose, 7 volts / cm, 45 min)
• Spectrophotometric analysis of an aliquot (1μl) (nanodrop photometer)

2.3 Results and discussion

The four different approaches with the leaf tissue quantities used are summarized in the following table: No. approach Wet weight [grams] 1 REB14-O 1.63 2 REB15-O 1.64 3 REB14-SQ 1.66 4 REB15-SQ 1.68

The digestion according to the invention led to a high-grade and homogeneous comminution of the tobacco leaves with tissue particles of less than 1 mm in diameter.

In the 4A documented gel electrophoretic analysis showed that the sample digestion with the vessels according to the invention leads to a qualitatively excellent RNA. The spectrophotometric analysis of the RNA samples (s. 4B ) confirmed the high quality of the RNA samples using the vessels of the invention (A260 / A280 quotient ~ 2.0). In addition, the method according to the invention led to an increased RNA yield which was 128% and 114% higher than the DNA yield achieved by the comparison method.

3. Purification of DNA or RNA from tobacco leaves with the predominantly conical vessels

3.1 Question

In this experiment, the RNA isolation is compared with grinding balls in conventional round vessels with the use of the same grinding balls in the conical vessels according to the invention. The material used is fresh tobacco leaves, which are a difficult substrate for RNA isolation.

3.2 Material and Methods

See embodiments 1 & 2.

3.3 Results and discussion

The purification of the DNA or RNA was carried out according to the embodiments 1 & 2 and led to similar results. The respective yields of DNA or RNA were higher using the vessels according to the invention than with the use of conventional vessels.

Other variants of the invention and their execution will become apparent to those skilled in the art from the foregoing disclosure, the drawings and the claims.

definitions

According to the invention, the cross-section of the interior of the tubular vessel (also referred to as "inner tube section") is defined as that section through the tubular vessel which is perpendicular to its longitudinal axis, which as such extends from the vessel opening to the vessel bottom and the usually rotationally symmetric ones round vessels represents the rotation axis.

In the context of the present invention, a "turbulent flow" is defined as a flow in which the formation of a simple or complex flow funnel is inhibited and in which turbulence occurs over a wide range of size scales. This flow form is characterized by a mostly three-dimensional flow field with a temporally and spatially apparently randomly varying component.

In the context of the invention, a "digestion of biological samples" means a comminution of the samples in which cellular structures are preferably broken up as well.

In the context of the present invention, laboratory use means any technical or scientific use that is accompanied by controlled reaction conditions, thus encompassing use in research and development as well as for analysis, diagnosis, quality assurance, or pathological or forensic analysis. The laboratory use according to the invention comprises the storage of biological materials of any kind, including viruses, phages and bacteria. Furthermore, this includes processes such as Cryoconservation, freezing of samples, the preparation of stock solutions, the production of aliquots, etc. Finally, this also means the mixture of liquids, and in particular of highly viscous liquids, or else the solubilization of solids (such as powder or (salt) crystals in liquids).

According to the invention, "samples" are defined as any material that can be used in the laboratory. According to the invention, this includes both inorganic and organic samples, and in particular biological samples such as tissue samples, bone samples, plant samples or bacterial samples.

Terms used in the claims, such as "comprising," "comprising," "including," "containing," and the like, do not exclude other elements or steps. The use of the indefinite article does not exclude a majority. A single device can perform the functions of several units or devices mentioned in the claims. Reference signs indicated in the claims should not be regarded as limitations on the means and steps employed.

According to the invention, "conical" is defined as tapering downwards or towards the bottom of the vessel.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• EP 1792657 A1 [0003]
• GB 2432667 A [0004]
• DE 690273 A [0005]
• US Pat. No. 2,847,169 A [0006]

Claims (11)

A vessel for the mechanical digestion of biological samples comprising a tubular vessel having a bottom of the vessel and at the top a vessel opening, characterized in that the interior of the tubular vessel has a conical shape occupying more than 70% of the length of the vessel in that the biological sample contained in the vessel is set into a turbulent flow during a movement substantially parallel to the longitudinal axis of the vessel. Vessel according to claim 1, characterized in that the conical region of the tubular vessel occupies more than 75% of the length of the vessel, preferably more than 80%, more preferably more than 85% and in particular more than 90%. A vessel according to claim 1 or 2, characterized in that the conical region of the tubular vessel has a length of at least 5 mm, preferably of at least 7.5 mm and more preferably of at least 10 mm. A vessel according to any one of the preceding claims, characterized in that the vessel has a vessel volume of from 0.2 ml to 20 liters, preferably from 1 ml to 50 ml, and especially from 1.5 ml, 2 ml, 2.5 ml, 3 ml , 5 ml, 15 ml, 20 ml or 50 ml. Container according to one of the preceding claims, characterized in that the vessel is provided on the opening side with an internal or external thread to the closure with a screw cap. Container according to one of claims 1 to 5, characterized in that it has a lid, which is connected by means of a preferably designed as a flat web web with the vessel in the region of the vessel opening. A vessel according to claim 6, characterized in that the vessel is provided with locking means for releasably locking the lid. Use of the vessel according to one of the preceding claims for the mixing or comminution of samples, and in particular for the digestion of biological cell samples, by shaking or rotary mixing and in particular by rapid movement of the vessel along its longitudinal axis. Use of the vessel according to claim 8, characterized in that the samples are comminuted or digested with the addition of grinding media by the shaking or rotation mixture. A method of digesting biological samples comprising the following steps: a. Filling a vessel according to one of claims 1 to 7 with a biological sample and grinding media according to claim 10 and optionally with a solvent; b. Optional closure of the vessel; c. Digesting the sample by shaking, oscillating or rotating the vessel prepared according to steps a and b, preferably using a vibrating mill or a "bead beater". Kit for digesting biological samples comprising: a. At least one vessel according to one of claims 1 to 7 b. Grinding bodies according to claim 9; and c. Optionally at least one buffered aqueous solution.

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