JPH03247268A - Sucking and discharging device for cell - Google Patents

Abstract

PURPOSE:To perform a slight change of volume in high reproducibility, to miniaturize the device and to facilitate the operation by varying the volume in a vessel by the displacement of a piezoelectric element to effect the suction and discharge of cells. CONSTITUTION:The displacement of a piezoelectric element can be reversibly and continuously controlled by the control of applied voltage. Since the displacement of piezoelectric element is extremely small, the element is convenient for the delicate operation of the suction and discharge of cells. The tip end of a capillary tube is brought close to a cell in a cell suspension liquid and a voltage is applied to the piezoelectric element in a direction to increase the inner volume of the vessel and suck the cell into the capillary. Thereafter, the tip end of the capillary tube is moved to a prescribed position and a voltage is applied to the piezoelectric element in a direction to decrease the inner volume of the vessel and discharge the cell sucked to the capillary tube.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a cell suction/discharge device used in the field of biotechnology to capture specific cells from a cell population in a cell suspension. be.

(Prior Art) In conventional cell suction/discharge devices, cells are suctioned and discharged by attaching a thin tube for sucking and discharging cells to a microsyringe, or by connecting the thin tube to a pump.

(Problems to be Solved by the Invention) The change in volume for aspirating or discharging cells is extremely small, and it is difficult to control such a small volume change with a microsyringe or a pump.

In order to bring the suction tube close to specific cells in the cell suspension, it is necessary to move the cell suction/discharge device freely, but connecting it to a microsyringe or pump makes it lighter and more compact. There is a problem.

The purpose of the present invention is to provide a cell suction/discharge device that can control the suction and discharge of minute amounts of liquid necessary for suctioning and discharging cells, and is also advantageous in terms of weight and size reduction. That is.

In the cell suction/discharge device of the present invention, a thin tube is provided in a container whose wall part is made of a piezoelectric element, and the internal space of the container is connected to the outside only through the thin tube. This container is attached to an arm that can be moved to any position, and by controlling the applied voltage to the piezoelectric element, the volume of the internal space is changed through displacement of the piezoelectric element, and cells are aspirated and discharged through the thin tube.

(Function) The amount of displacement of the piezoelectric element can be reversibly and continuously controlled by the applied voltage. In addition, the amount of displacement of the piezoelectric element is small, which is convenient for performing fine operations such as suction and discharge of cells.

Cells are attracted into the tubule by bringing the tip of the tubule close to the cells in the cell suspension and applying a voltage to the piezoelectric element in a direction that increases the volume of the internal space of the container. Thereafter, the tip of the capillary is moved to a predetermined position, and a voltage is applied to the piezoelectric element in a direction that reduces the volume of the internal space of the container, causing the cells that had been sucked into the capillary to be discharged.

(Example) The figure represents one embodiment.

2 is a container, one wall of which is constituted by a piezoelectric element 4. A capillary tube 6 is attached to the container 2, and the interior space 8 of the container 2 communicates with the outside only through the capillary tube 6.

The piezoelectric element 4 is a bimorph type piezoelectric element, and has a structure in which two piezoelectric elements polarized in the same direction are bonded together with a metal plate sandwiched between them. By applying a voltage between the two piezoelectric elements, it is possible to cause the bimorph piezoelectric element 4 to warp.

The direction of warpage of the bimorph piezoelectric element 4 depends on the polarity of the applied voltage, and the amount of warpage depends on the magnitude of the applied voltage.

A lead wire 1o of the piezoelectric element 4 is connected to a DC voltage generation circuit 12 that generates a drive voltage. Reference numeral 14 denotes a control circuit, in which a DC drive voltage is generated from the DC voltage generation circuit 12 in accordance with a control voltage from the control circuit 14 and is applied to the piezoelectric element 14 .

The container 2 is attached to a support arm 16.

The support arm 16 is attached to a micromanipulator (path shown), and can move the container 2 in any direction of x, y, or z.

18 is a container containing the cell suspension 20;
represents the cells to be aspirated.

Although not shown in the figure, an inverted microscope f is provided below the container 18 in order to position the tip of the thin tube 6 at the position of the cell 22.
A mirror is provided, and the tip of the tubule 16 is positioned while viewing the cells 22 using the inverted microscope.

Next, the operation of this embodiment will be explained.

The area of the piezoelectric element 4 is S. Binding, driving voltage E. , the piezoelectric element 4 is displaced Q0 in the direction of decreasing the volume of the internal space 8, then the volume reduction Δ■
Since o=S0·Qo, the air in the internal space 8 is pushed out by Δvo. A driving voltage E is applied to the piezoelectric element 4 while the tip of the capillary tube 6 is not immersed in the cell suspension. is applied, and the internal space 8
Reduce the volume of.

The tip of the thin tube 6 is immersed in the cell suspension 20 while the driving voltage E0 is applied, and the support arm 16 is moved to position the tip of the thin tube 6 near the cells 22 to be captured by suction.

It is assumed that the driving voltage E of the piezoelectric element 4 satisfies E<E. As a result, the volume of the internal space 8 of the container 2 increases, and the cells 22 are captured within the thin tube 6.

Next, after moving the support arm 16 to an arbitrary location, the drive voltage E of the piezoelectric element 4 is set to E>Eo.

As a result, the piezoelectric element 4 is displaced to Q, and the volume of the internal space 8 of the container 2 is further reduced compared to the state before the cells were sucked, so that the cells sucked into the thin tube 6 are discharged.

The change in volume of the internal space 8 required for suction and ejection of cells is μQ
unit, and such a minute volume change can be realized by displacement of the piezoelectric element 4.

The cycle of aspiration and ejection of cells can be repeated at arbitrary cycles, for example, from 0 to several hundred Hz.

As another use of this embodiment, for example, a solution of proteins, genes, etc. can be sucked into the thin tube 6 in advance, and after the thin tube 6 is pierced into a specific cell, the protein, gene, etc. can be discharged. This allows proteins, genes, etc. to be injected into cells.

(Effects of the Invention) In the present invention, the volume of the internal space of the container connected to the thin tube for aspirating and discharging cells is changed by displacement of the piezoelectric element, so that cells can be aspirated and discharged.
It is possible to realize minute changes in volume with good reproducibility.

Since the volume is changed using a piezoelectric element, this cell suction/discharge device only needs to be connected to a lead wire that supplies a perturbation voltage, which makes it easier to use than conventional cell suction/discharge devices that are connected to microsyringes or pumps. It can be made lightweight and compact, making it easy to handle.

[Brief explanation of drawings]

The figure is a sectional view showing one embodiment. 2... Container, 4... Piezoelectric element, 6... Thin tube,
8...Internal space, 12...DC voltage generation circuit, 14...Control circuit, 22...Cell.

Claims (1)

[Claims] (1) A part of the wall surface of a container having a thin tube and whose internal space is connected to the outside only through the thin tube is a piezoelectric element, and it is attached to an arm that can be moved to any position, and the voltage applied to the piezoelectric element is A device that changes the volume of an internal space through the displacement of a piezoelectric element under control of the device, and aspirates and discharges cells using the thin tube.