JPH0659632B2 - Fine object handling device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a fine object manipulating apparatus capable of sandwiching or rotating a fine object such as a cell.

[Conventional technology]

Conventionally, there is a technique called micromanipulation as a technique for manipulating individual cells. This is a technique in which an operation tool for operating cells is attached to, for example, the tip of a hydraulic linear motor and electrically operated by a joystick or the like to perform operations such as aspiration, cutting, injection, and selection of cells under a microscope. .

In cell manipulation, it is said that it is necessary to manipulate cells having a size of about 10 to 300 μm and nuclear plasmids (DNA fragments other than chromosomes in cells) of 5 to 10 μm therein.

When performing such cell manipulation with a conventional micromanipulator, there were the following problems.

Only linear operation is possible.

Poor positioning accuracy.

Arms are too long and susceptible to external vibration.

It is difficult to delicately control how to apply force during intracellular injection, enucleation, and cutting.

A piezoelectric actuator using a piezoelectric element as a drive source has the following features.

Highly accurate positioning of 0.1 μm or less is possible.

It is fast and compact.

Not only linear displacement, but also flexible mechanical operations such as bending, twisting, and excitation of surface waves are possible.

The present inventors have studied the application of a piezoelectric actuator to a micromanipulator by paying attention to the above characteristics, and have developed piezoelectric tweezers that do not have various drawbacks of conventional manipulators. The piezoelectric tweezers that have already been applied utilize the characteristics of the piezoelectric actuator as described above.

FIG. 8 is a diagram showing an outline of the piezoelectric tweezers.
As shown in FIG. 8, the tweezers body 1 is joined to the piezoelectric elements 2a and 2b made of a piezoelectric bimorph or a laminated piezoelectric material, and a voltage of a predetermined polarity is applied to the terminals T1 and T2 to operate the piezoelectric elements. Tweezers tip 3a,
The cell 3 is clamped by opening and closing the legs 3b. In FIG. 8, 5 is a stage, 6 is a cell provided on the stage, and 7 is a microscope objective lens.

According to the above-mentioned piezoelectric tweezers, it becomes possible to pinch and operate a fine object such as a cell with high accuracy. However, this piezoelectric tweezers does not have a function of rotating the cells at the position before holding the cells floating in the chassis or the like. However, when actually manipulating cells, for example, when carrying out an experiment such as nuclear transfer to a fertilized egg of a mouse or the like, the fertilized egg should be placed in the same plane based on the pronucleus of the male and female in the fertilized egg to be transplanted After moving it, it is necessary to hold it. In such a case, first, an operation of rotating the egg cell at that position is required.

FIG. 9 is a diagram showing a conventional means for performing such cell rotation. This means utilizes the flow a of the cell suspension liquid by the suction and discharge of the micropipette 8
It is designed to give a rotating force to the arrow.

[Problems to be solved by the invention]

However, with the above rotating operation means, the suspension cannot be sucked in the vicinity of the cells 4 to be manipulated, and it is very difficult to determine the direction in which the sucked suspension is discharged. For this reason, it is not possible to repeatedly perform a highly accurate rotation operation. There is also a problem that the cells 4 are moved when the suspension is discharged. Especially when the cells 4 are moved out of the microscope field,
There was a problem that it became impossible to manipulate cells under a microscope.

Therefore, an object of the present invention is to provide a fine object manipulating device having a high degree of freedom, in which not only a micro object such as a cell can be sandwiched but also a swiveling operation can be swiftly and appropriately performed.

[Means for solving problems]

The present invention has taken the following means in order to solve the above problems and achieve the object. That is, a plurality of sandwiching members capable of sandwiching a fine object were provided, and at least one of these sandwiching members was equipped with a piezoelectric element capable of being bent and displaced in two directions so as to impart rotational movement to the fine object.

[Action]

By taking such a means, it is possible not only to hold a fine object such as a cell but also to rotate the object at a proper time.

Next, details of the present invention will be described with reference to the drawings. 1 to 3 are views showing the outline of the fine object manipulating apparatus of the present invention. FIG. 1 is a diagram showing the basic structure of a piezoelectric bimorph used in this apparatus. In the figure, 10 is a base end block, and a fixing screw hole 10a is provided in the central portion. 11
Is a metal plate integrally formed with the base block 10, and has a clamping leg mounting hole 11a at its tip and a fixing screw hole 11b orthogonal to the mounting hole 11a. Reference numeral 12 denotes a piezoelectric element having a bimorph structure, which is mounted on the back surface of the metal plate 11. This piezoelectric element 1
Reference numeral 2 has a structure in which a plurality of piezoelectric plates are bonded together, or a piezoelectric plate and a metal plate, or a piezoelectric plate and a glass plate are laminated together, and a voltage can be applied to them from terminals T1 and T2. .

When a voltage having a predetermined polarity is applied, the piezoelectric bimorph changes its bending direction according to its voltage polarity and changes its bending degree according to the magnitude of the voltage. Therefore, by controlling the voltage application, the tip of the piezoelectric bimorph is displaced so as to draw a circular motion, so that a rotational force can be applied to the cell. In this case, if circular or elliptical movement does not occur, cells in close proximity cannot be rotated. Further, if only one piezoelectric bimorph is moved in a circular or elliptic manner, cells may escape from the field of view of the microscope.

FIG. 2 is a diagram showing means for preventing this. As shown in the figure, the tip of the piezoelectric bimorph for rotation operation (not shown)
A support member 21 having a cell-facing surface formed into a concave spherical surface is provided so that the cells 4 can be fixed so as to face the cell 4.
By using such a support member 21, the cells 4 can be held in place even when the cells 4 are given a circular or elliptical movement 22. As the supporting member 21, a plurality of other piezoelectric bimorphs (for example, three or more in total) may be used. However, the piezoelectric bimorph is not always necessary, and it may be made of a glass or plastic material having a tip shape that can be fixed.

In the present invention, it is important that the displacement locus of the tip portion of the piezoelectric bimorph is a circle or an ellipse. However, in the structure shown in FIG. 1, since the vibration is merely a pendulum type reciprocating displacement, a minute rotational motion is possible, but 360
There is a problem in rotating a large angle such as rotating by °.

FIG. 3 shows a piezoelectric bimorph constructed in consideration of such a point. That is, 31 is an elastic metal square bar, and the first and second piezoelectric elements 32a and 32b are joined to the surfaces of this elastic metal square bar 31 that differ by 90 °. With such a configuration, it is possible to change the two orthogonal directions A and B, and by changing the phase and the amplitude between the two displacements, it is possible to reliably generate a circular motion or an elliptic motion.

〔Example〕

FIG. 4 is a perspective view showing the first embodiment of the present invention. The present embodiment is a fine object manipulating apparatus having a structure in which the supporting member shown in FIG. 2 and the piezoelectric bimorph shown in FIG. 3 are combined. In the figure, reference numeral 40 denotes a fixing member serving as one holding member formed of a metal rod whose surface is treated with a glass film or a chemically stable resin material, and a head 40a having a concave spherical surface for fixing cells is provided at the tip thereof. It is provided. Reference numeral 41 is a metal square rod as the other holding member, and the first and second piezoelectric elements 42a and 42b are joined to the two different surfaces thereof. A glass rod 43 for rotating operation is attached to the tip attachment hole of the bidirectional displacement piezoelectric bimorph thus formed. Although the other end is not shown in FIG. 4, each other end may be fixed to a separate pedestal,
It goes without saying that they may be fixed to a common pedestal.

In the present device configured as described above, various combinations of the phase difference ψ and the amplitude ratio K between the AC voltage applied to the first piezoelectric element 42a and the AC voltage applied to the second piezoelectric element 42b are used. The trajectory drawn by the tip of the glass rod 43 can be variously changed. For example, when ψ = 0, the motion is linear, and when K is changed at the same time, the angle with respect to the horizontal plane changes. Also, when ψ = 90 °, K =
When it is set to 1, a circular motion is performed, and when K ≠ 0, an elliptical motion is performed. In this way, it is possible to realize a device for manipulating a fine object having a high degree of freedom of operation, particularly a device capable of appropriately rotating cells.

FIG. 5 is a perspective view showing a second embodiment of the present invention. In this embodiment, the fixing member for supporting the cells as in the above embodiments is not specially provided, but three piezoelectric bimorphs 51, 52 and 53 are provided instead.

In the present embodiment having such a configuration, two of the piezoelectric bimorphs 51 to 53 serve as the fixing member, and the remaining one serves as a member for rotating and operating cells. Therefore, it is not necessary for two of the three to be piezoelectric bimorphs in particular, but not only the sandwiching and rotation of the cells 4 but also the case of intentionally deforming the cells may be simultaneously performed. In this case, it can be said that the utility value is higher when all the three piezoelectric bimorphs are used. Although the wiring of the lead wire to the piezoelectric element is omitted in FIG. 5, it is the same as in the first embodiment.

FIG. 6 is a perspective view showing a third embodiment of the present invention. In this embodiment, two piezoelectric bimorphs 61 and 62 that are bent and displaced in two directions are attached to one side of the L-shaped fixing member 60.
Another piezoelectric bimorph 63 is attached to the other side of the L-shaped fixing member 60.

As described above, in this embodiment, the plurality of piezoelectric bimorphs are arranged so that the mounting directions thereof are orthogonal to each other.
As shown in FIG. 7, it is possible to make the rotation direction by the piezoelectric bimorphs 61 and 62 and the rotation direction by the piezoelectric bimorph 63 orthogonal to each other. Therefore, for example, the operation of moving the pronuclei of the male and female in the fertilized egg to be transplanted so as to come to the same plane can be easily performed.

The present invention is not limited to the above-mentioned nuclear embodiment,
Needless to say, various modifications can be made without departing from the scope of the present invention.

〔The invention's effect〕

According to the present invention, a plurality of sandwiching members capable of sandwiching a fine object are provided, and at least one of these sandwiching members is provided with a piezoelectric element that can be bent and displaced in two directions so as to impart rotational motion to the fine object. Therefore, it is possible to sandwich a fine object such as a cell, and it is possible to rotate a fine object such as a cell quickly and accurately and in a timely manner, and it is possible to provide a fine object operating device having a high degree of freedom in operation.

[Brief description of drawings]

1 to 3 are views showing the outline of the fine object manipulating apparatus of the present invention. 4 is a perspective view showing a first embodiment of the present invention, FIG. 5 is a perspective view showing a second embodiment of the present invention, FIG. 6 is a perspective view showing a third embodiment of the present invention, and FIG. The figure is a diagram showing the operation of the third embodiment. FIG. 8 is a diagram showing an outline of piezoelectric tweezers, and FIG. 9 is a diagram showing a conventional means for imparting rotation to cells. 10 ... Base end block, 11 ... Metal plate, 12 ... Bimorph structure piezoelectric element, 21 ... Support member, 31 ... Elastic metal square bar, 32a, 32b ... First and second piezoelectric elements, 40: fixing member, 41: elastic metal square bar, 41,
42 ... First and second piezoelectric elements, 51, 52, 53 ...
Piezoelectric bimorph, 60 ... L-shaped fixing member, 61-63
...... Piezoelectric bimorph.

Claims (3)

[Claims] 1. A rectangular rod-shaped elastic body having one end fixed, first and second electric-mechanical energy conversion elements respectively provided on surfaces orthogonal to the extending direction of the rectangular rod-shaped elastic body, A fine object manipulating apparatus comprising: a rod-shaped elastic body joined to the other end of the rod-shaped elastic body; and a sandwiching portion provided so as to face a tip end portion of the rod-shaped elastic body. 2. A prismatic elastic body, and first and second prisms respectively provided on surfaces orthogonal to the extending direction of the prismatic elastic body.
The electro-mechanical energy conversion element of, and a plurality of vibrating body composed of a rod-shaped elastic body joined to one end of the square rod-shaped elastic body, the plurality of vibrating body at the other end of the square bar-shaped elastic body. A fine object manipulating device characterized in that they are respectively coupled. 3. A rectangular rod-shaped elastic body having one end fixed, and first and second electric-mechanical energy conversion elements provided on surfaces orthogonal to the extension direction of the rectangular rod-shaped elastic body, respectively.
A plurality of vibrating bodies including a bar-shaped elastic body joined to the other end of the rectangular bar-shaped elastic body are provided, and the plurality of vibrating bodies are provided orthogonally to the extension direction of the respective rectangular bar-shaped elastic bodies. A fine object manipulating device characterized in that