METHOD FOR ADJUSTING A CELL CONCENTRATION AND/OR PARTICLE CONCENTRATION IN A DISPENSING SYSTEM

Abstract

The invention relates to a method for setting a cell concentration and/or a particle concentration in a dispensing device that has a fluid chamber into which a liquid sample is introduced that has a liquid and cells and/or particles, wherein the cell concentration and/or the particle concentration is determined, in particular in one region of the dispensing device, and the cell concentration and/or particle concentration that has been determined is compared with a target value and the cells and/or particles, in particular one or the other, that are present in the fluid chamber are moved or not moved as a function of the result of the comparison.

Claims

1. A method for setting a cell concentration and/or a particle concentration in a dispensing device (3) having a fluid chamber (5) into which a liquid sample (21) is introduced, the liquid sample (21) including a liquid (7) and cells (6) and/or particles, the method comprising: determining the cell concentration and/or the particle concentration in one region of the dispensing device; comparing the determined cell concentration and/or particle concentration with a target value; and moving or not moving the cells and/or particles present in the fluid chamber (5) as a function of the result of the comparison.

2. The method according to claim 1, wherein the cells (6) and/or particles present in the fluid chamber (5) are moved if the determined cell concentration and/or particle concentration is less than the target value.

3. The method according to claim 1, wherein the cells (6) and/or particles present in the fluid chamber (5) are moved less strongly in a state in which the cell concentration and/or particle concentration is greater than the target value than in another state in which the cell concentration and/or particle concentration is less than the target value.

4. The method according to claim 1, wherein the cells (6) and/or particles are not moved if the determined cell concentration and/or particle concentration is greater than the target value or equal to the target value.

5. The method according to claim 1, further comprising dispensing liquid sample (21) from the dispensing device (3) after moving the cells (6) and/or particles, and/or after waiting a predetermined time after determining the cell concentration and/or the particle concentration.

6. (canceled)

7. The method according to claim 1, wherein moving the cells and/or particles present in the fluid chamber (5) comprises alternately suctioning a portion of the liquid sample (21) present in the fluid chamber (5) into a tubing (9) and discharging into the fluid chamber (5) at least a portion of the liquid sample (21) present in the tubing (9).

8. (canceled)

9. The method according to claim 7, wherein the portion of the liquid sample (21) suctioned into the tubing (9) is kept in the tubing (9) for a predetermined time, and after the predetermined time has elapsed, another portion of the suctioned-in liquid sample (21), which is smaller than the suctioned-in portion of the liquid sample (21), is discharged into the fluid chamber (5), and wherein the discharged other portion of the suctioned-in liquid sample (21) has a higher cell concentration and/or particle concentration than the portion of the liquid sample (21) that remains in the tubing (9).

10. (canceled)

11. (canceled)

12. (canceled)

13. The method according to claim 1, wherein determining the cell and/or particle concentration comprises ejecting a portion of the liquid sample (21) from the dispensing device (3), generating an image of the ejected portion of the liquid sample, and detecting cells and/or particles contained in the ejected portion of the liquid sample from the image.

14. (canceled)

15. The method according to claim 1, wherein determining the cell and/or particle concentration comprises generating an image of at least one region of a discharge tubing (11) of the dispensing device (3) in which a portion of the liquid sample (21) to be discharged is present and detecting cells and/or particles contained in the portion of the liquid sample from the image.

16. (canceled)

17. (canceled)

18. (canceled)

19. The method according to claim 1, further comprising actuating a section (13) of the dispensing device to dispense a liquid drop (4) of liquid sample (21) from the dispensing device through a discharge tubing (11) of the dispensing device, wherein liquid sample (21) flows from the fluid chamber (5) into the discharge tubing (11) after the liquid drop (4) is dispensed.

20. The method according to claim 1, further comprising dispensing liquid sample (21) from the dispensing device according to a drop-on-demand mode of operation.

21. (canceled)

22. The method according to claim 1, wherein the cell concentration and/or particle concentration is controlled such that the cell concentration and/or particle concentration reaches the target value or a value within a predetermined range of the target value.

23. A dispensing apparatus (1) comprising: a dispensing device (3) including a fluid chamber (5) into which a liquid sample (21) is introduced, wherein the liquid sample (21) includes a liquid (7) and cells (6) and/or particles, the dispensing device (3) further including a mixing means (9, 16) for mixing the liquid sample (21) in the fluid chamber (5) to move the cells and/or particles; an imaging apparatus (10) arranged to generate an image of a portion of the liquid sample (21) present in a region of the dispensing device (3) and/or in a liquid drop (4) of liquid sample (21) dispensed from the dispensing device (3); an evaluation apparatus (12) configured to evaluate the image to ascertain information including whether the imaged portion of the liquid sample (21) has a cell (6) or a particle, and/or ascertain a number of cells or particles in the imaged portion of the liquid sample (21); and a control apparatus (2) connected to the evaluation apparatus (12) and the mixing means; wherein the control apparatus (2) or the evaluation apparatus (12) is configured to determine a cell concentration and/or a particle concentration in the imaged portion of the liquid sample (21) based on the information ascertained by the evaluation apparatus (12); and wherein the control apparatus (2) is configured to compare the determined cell concentration and/or particle concentration with a target value, and operate or not operate the mixing means as a function of the result of the comparison.

24. (canceled)

25. The dispensing apparatus (1) according to claim 23, wherein the control apparatus (2) is configured to operate the mixing means to cause the cells (6) and/or particles to move if the determined cell concentration and/or particle concentration is less than the target value.

26. The dispensing apparatus (1) according to claim 23, wherein the control apparatus (2) is configured to operate the mixing means to cause the cells and/or particles to be moved less strongly in a state in which the cell concentration and/or the particle concentration is greater than the target value than in a different state in which the cell concentration and/or the particle concentration is less than the target value.

27. The dispensing apparatus according to claim 23, wherein the control apparatus (2) is configured to not operate the mixing means for a predetermined period of time if the determined cell concentration and/or particle concentration is greater than the target value or equal to the target value.

28. (canceled)

29. The dispensing apparatus (1) according to claim 23, wherein the mixing means comprises a tubing (9) in communication with the fluid chamber (5) and a pressure unit or pump unit (16) connected to the tubing (9) and to the control apparatus (2), the control apparatus (2) being configured to operate the pressure unit or pump unit (16) to suction a portion of the liquid sample (21) into the tubing (9) and cause the suctioned-in portion of the liquid sample (21) to be held in the tubing (9) for a predetermined period of time.

30. The dispensing apparatus (1) according to claim 23, wherein the dispensing device includes a discharge tubing (11) in flow communication with the fluid chamber (5), and the control apparatus (2) is configured to set the cell concentration and/or particle concentration in the discharge tubing (11) or a region of the discharge tubing (11).

31. (canceled)

32. (canceled)

33. The dispensing apparatus (1) according to, further comprising an actuating means (14) for actuating a section (13) of the dispensing device (3) for discharging liquid sample (21) from the dispensing device (3).

34. (canceled)

35. (canceled)

36. A non-transient computer readable storage medium comprising a computer program comprising commands that, when the computer program is executed by a computer, cause the computer to carry out the method according to claim 1.

37. (canceled)

38. (canceled)

Description

BRIEF DESCRIPTION OF THE DRAWING VIEWS

[0065] The subject matter of the disclosure is shown schematically in the figures, wherein elements that are the same or have the same effect are mostly provided with the same reference symbols. In the figures:

[0066] FIG. 1 shows a dispensing apparatus according to the disclosure in a state in which a drop of liquid is discharged,

[0067] FIG. 2 shows a dispensing device of the dispensing apparatus according to the disclosure, in a state in which the cell concentration in a discharge tubing of the dispensing device is too low,

[0068] FIG. 3 shows the dispensing device of the dispensing apparatus according to the disclosure, in a state in which the cell concentration in the discharge tubing is too low, after a portion of the liquid sample present in a fluid chamber has been suctioned into a tubing,

[0069] FIG. 4 shows the dispensing device of the dispensing apparatus according to the disclosure after dispensing the liquid sample that has been suctioned into the tubing,

[0070] FIG. 5 shows the dispensing device of the dispensing apparatus according to the disclosure, after a predetermined time has elapsed after the liquid sample has been suctioned into the tubing,

[0071] FIG. 6 shows the dispensing device of the dispensing apparatus according to the disclosure, after a portion of the liquid sample that has been suctioned in has been discharged from a tubing,

[0072] FIG. 7 shows the dispensing device of the dispensing apparatus according to the disclosure in a state in which the cell concentration in the discharge tubing is too high,

[0073] FIG. 8 shows the dispensing device of the dispensing device shown in FIG. 7 after a predetermined period of time.

DETAILED DESCRIPTION

[0074] FIG. 1 shows: a dispensing apparatus 1 that has a dispensing device 3 for discharging a liquid drop 4, and a tubing 9 that has been inserted into the dispensing device 3. A liquid sample 21 is arranged in a part of the fluid chamber 5. The liquid sample 21 has a liquid 7 and cells 6. In the state shown in FIG. 1, the cells 6 are almost homogeneously distributed within the liquid 7 that is arranged in the fluid chamber 5.

[0075] Furthermore, the dispensing apparatus 1 has an imaging apparatus 10 for generating an optical image and an evaluation apparatus 12. The evaluation apparatus 12 is used to evaluate the generated image. In particular, by means of the evaluation apparatus 12 it can be ascertained whether the liquid drop 4 to be discharged, or liquid drop 4 that has been discharged from the dispensing device 3, has a cell 6. Alternatively or additionally, the number of cells arranged in the discharge tubing 11 or in a region of the discharge tubing 11 or in the discharged liquid sample 21, and thus the cell concentration, can be ascertained by means of the evaluation apparatus 12.

[0076] The dispensing apparatus 1 has a control apparatus 2 that is electrically connected to the evaluation apparatus 12 and is part of a computer that is not shown in greater detail. The control apparatus 2 is also electrically connected by means of a pressure or pump unit 16, which is fluidically connected to the tubing 9. By means of the pressure or pump unit 16, whether an overpressure or underpressure is present in the tubing 9 can be adjusted. Alternatively or additionally, the pressure or pump unit 16 can be designed in such a way that the tubing 9 is vented after the overpressure has been generated. To this end, the tubing 9 is fluidically connected to the environment.

[0077] The control apparatus 2 determines the cell concentration in the discharge tubing 11 or in the region of the discharge tubing 11 based on the information provided by the evaluation apparatus 12. In addition, the control apparatus 2 checks whether the cell concentration is less than or greater than a target value or equal to the target value. Depending on the result of this check, the pressure or pump unit 16 is controlled by the control apparatus 2 so as to apply an underpressure or an overpressure in the tubing 9.

[0078] The liquid drop 4 is discharged from the dispensing device 3 if the dispensing device 3 is actuated by means of an actuating means 14. This actuating means 14 may be a piezo-electric actuator that deforms a section 13 of the dispensing device 3 in order to discharge the liquid drop 4.

[0079] FIG. 2 shows the dispensing apparatus 1 according to the disclosure, in a state in which the cell concentration in the discharge tubing 11 of the dispensing device 3 is too low. This means that the control apparatus 2 has determined, based on the information provided by the evaluation apparatus 12, that the cell concentration in the region of the discharge tubing 11 or in the discharge tubing 11 is less than the target value.

[0080] This state can arise if a plurality of cells 6 accumulate at a bottom of a fluid chamber 17, as is apparent in FIG. 2. In this case, after a liquid drop 4 has been discharged from the dispensing device 3, a portion of the liquid sample 21 present in the fluid chamber 5 flows into the dispensing device 3. As is apparent from FIG. 2, the cell concentration of the liquid sample 21 in a region 18 of the fluid chamber 5 adjacent to the discharge tubing 11 is very low, such that a large number of dispensing operations tend to have to be performed in order for cells 6 to flow into the discharge tubing 11 together with liquid from the fluid chamber 5.

[0081] In order to rapidly increase the cell concentration in the discharge tubing 11, the control apparatus 2 causes the liquid sample 21 present in the fluid chamber 5 to be set in motion. This is described in greater detail with reference to FIGS. 3 and 4, in which agitation of the liquid sample 21 present in the fluid chamber 5 is achieved by mixing the liquid sample 21.

[0082] FIG. 3 shows the dispensing apparatus 1 in a state in which a portion of the liquid sample 21 present in the fluid chamber 5 has been suctioned into the tubing 9. In particular, an underpressure is applied in the tubing 9 by means of the pressure or pump unit 16, so that a portion of the liquid sample 21 present in the fluid chamber 5 is suctioned into the tubing 9. FIG. 4 shows the dispensing apparatus 1 in a state in which the portion of the liquid sample 21 suctioned into the tubing 9 in FIG. 3 has been discharged from the tubing 9 such that there is no longer any liquid sample 21 in the tubing 9. This can be realised by applying an overpressure in the tubing 9 by means of the pressure or pump unit 16.

[0083] The suctioning in of the liquid 7 into the tubing 9 and the discharge of the liquid 7 from the tubing 9 occur alternatingly. In addition, the suctioning in and out can be repeated multiple times in succession such that, as is apparent in FIG. 4, a more homogeneous distribution of the cells 6 in the fluid chamber 5 is achieved, in comparison to FIG. 3.

[0084] When a liquid drop 4 is discharged from the dispensing device 3, the region 18 of the fluid chamber 5 adjacent to the discharge tubing 11 has a higher cell concentration than is the case in the state shown in FIG. 3. Therefore, the probability is increased that cells 6 will flow into the discharge tubing 11 together with liquid after a dispensing operation. As a result, after one or more dispensing operations, the cell concentration increases in the discharge tubing 11 or in the region of the discharge tubing 11.

[0085] An agitation of the liquid 7 present in the fluid chamber 5, and/or an increase in the probability that liquid sample 21 having at least one cell will flow into the discharge tubing 11 after a dispensing operation, may additionally be realised by another method. This will be explained in greater detail with reference to FIGS. 3 and 5.

[0086] As described above, to realise the state shown in FIG. 3, a portion of the liquid sample 21 present in the fluid chamber 5 is suctioned into the tubing 9. In contrast to the process described with reference to FIG. 4, the suctioned-in portion of the liquid 7 is not discharged immediately after being suctioned in, but there is a delay of a predetermined length of time. The adjusted state after the time period has expired is shown in FIG. 5.

[0087] The portion of the liquid sample 21 suctioned into the tubing 9 has two liquid regions that differ from one another in cell concentration. In this case cells 6 that are present in the tubing 9 escape from the tubing 9 within the time period, such that the cell concentration and/or particle concentration increases in the liquid sample 21 that remains in the fluid chamber 5. In this case, a first liquid region 19 close to the bottom 17 of the fluid chamber has a higher cell concentration in the tubing 9 than a second liquid region 20. The second liquid region 20 is arranged within the tubing 9 above the first liquid region 19. The two liquid regions result from the fact that within the time period, the cells 6 sediment within the tubing 9 and therefore collect in the first liquid region 19 close to the bottom 17 of the fluid chamber.

[0088] After the predetermined time has expired, another portion of the liquid suctioned into the tubing 9 is discharged. The other portion is smaller than the portion suctioned into the tubing 9. In particular, the other portion discharged from the tubing 9 comprises the first liquid region 19 that has the high cell concentration. Because not all of the liquid 7 suctioned into the tubing 9 is discharged, but only the first liquid region 19 having the high cell concentration, the cell concentration in the remaining liquid sample 21 present in the fluid chamber 5 increases.

[0089] In addition, as a result of the liquid being suctioned in and discharged, a mixing of the liquid 7 in the fluid chamber 5 is achieved. In both cases it was advantageous that after a liquid drop 4 has been discharged from the dispensing device 3, cells 6 flow into the dispensing device 3 together with liquid 7, thus increasing the cell concentration in the discharge tubing 11. This occurs because more cells 6 are arranged in the region 18 of the fluid chamber 5 adjacent to the discharge tubing 11 than there were before the process was carried out, due to the above-described method.

[0090] FIG. 7 shows the dispensing apparatus 1 in a state in which the cell concentration in the discharge tubing 11 and/or a region of the discharge tubing 11 is too high. Thus, the cell concentration in the discharge tubing 11 or in a region of the discharge tubing 11 is greater than the target value.

[0091] To reduce the cell concentration present in the discharge tubing 11, for a certain period of time no agitation takes place of the liquid sample 21 in the fluid chamber 5, i.e. the liquid sample 21 is not set in motion. This causes the cells 6 to sediment on the bottom 17 of the fluid chamber, which reduces the cell concentration in the region 18 of the fluid chamber 5 adjacent to the fluid dispenser 8.

[0092] This state is shown in FIG. 8. In particular, in FIG. 8 it is apparent that a majority of the cells 6 present in the fluid chamber 5 are arranged at the bottom 17 of the fluid chamber.

[0093] To reduce the number of cells 6 present in the discharge tubing 11, a predetermined number of liquid drops 4 are then discharged, in particular after a predetermined period of time. The discharged liquid drops 4 are shown in FIG. 8 and each respectively have one or more cells. After each dispensing operation, a portion of the liquid sample 21 that is present in the region 18 adjacent to the discharge tubing 11 flows into the discharge tubing 11. Because the cell concentration of the liquid 7 flowing into the liquid dispenser 8 is low, the cell concentration in the discharge tubing 11 is also reduced as a result, as shown in FIG. 8. Thus, the cell concentration in the discharge tubing 11 is lower than in the state shown in FIG. 7.

LIST OF REFERENCE SIGNS

[0094] 1 Dispensing apparatus [0095] 2 Control apparatus [0096] 3 Dispensing device [0097] 4 Liquid drop [0098] 5 Fluid chamber [0099] 6 Cell [0100] 7 Liquid [0101] 9 Tubing [0102] 10 Imaging apparatus [0103] 11 Discharge tubing [0104] 12 Evaluation apparatus [0105] 13 Section of dispensing device [0106] 14 Actuating means [0107] 16 Pressure unit or pump unit [0108] 17 Fluid chamber base [0109] 18 Adjacent region [0110] 19 First liquid region [0111] 20 Second liquid region [0112] 21 Liquid sample