KR20170077475A

KR20170077475A - Electrode for dielectrophoresis based particle separation or capture

Info

Publication number: KR20170077475A
Application number: KR1020150187392A
Authority: KR
Inventors: 장재성; 한창호
Original assignee: 울산과학기술원
Priority date: 2015-12-28
Filing date: 2015-12-28
Publication date: 2017-07-06

Abstract

It is an object of the present invention to provide a dielectrophoretic-based particle separating and collecting device electrode having a novel type microelectrode structure capable of achieving optimal separation and collection efficiency in the same channel structure.
According to an aspect of the present invention, there is provided an electrode for a device for separating and collecting particles of a dielectrophoretic based particle formed on an inner surface of a channel formed with a constant cross section, ; A second horizontal electrode spaced apart from the first horizontal electrode by a predetermined distance; A third horizontal electrode spaced apart from the second horizontal electrode by a predetermined distance; A fourth horizontal electrode spaced apart from the third horizontal electrode by a predetermined distance; A fifth horizontal electrode formed at the other end of the channel inner surface in the longitudinal direction and spaced apart from the fourth horizontal electrode by a predetermined distance; A second vertical portion extending from one end of the second horizontal electrode to one end of the inner surface of the channel; A third vertical part formed at both ends of the third horizontal electrode and extending in the other end direction of the inner surface of the channel; And a fourth vertical portion formed at both ends of the fourth horizontal electrode and extending in the other end direction of the inner surface of the channel.

Description

Electrodes for dielectrophoresis-based particle separation or capture

The present invention relates to electrodes for dielectrophoretic-based particle separation and collection devices, and more particularly to electrodes for collection and collection of dielectrophoretic-based particles with good separation and collection efficiency.

Dielectrophoresis is a phenomenon in which dielectric particles that are not free-charged move to a larger or smaller electric field under a non-uniform electric field. In general, the magnitude of the force that can be obtained by such a dielectrophoresis phenomenon is very small, so that there is no example used in the conventional general mechanical system. However, recently, as the field of micro electro mechanical system (MEMS) As its size gets smaller, its use is rapidly increasing.

The above-mentioned dielectrophoresis phenomenon is widely used in the field of bio-MEMS, for example, separation of dead cells and living cells, separation of cancer cells and normal cells, separation of particles of different sizes or types, Etc., trapping, and changing the transport path.

The dielectrophoresis phenomenon of the above characteristic can be operated by only the electrode without any moving means and there is no need to label the sample. Especially, in the case of MEMS, since it can operate even at a small voltage of 10 V or less, And the success rate is very high in the case of cell separation and the like, and various configurations of the methods are proposed.

For example, Japanese Patent Application Laid-Open No. 2008-0087404 discloses a plasma display panel comprising a lower substrate, a plurality of strip-shaped first electrodes stacked in parallel on the upper surface of the lower substrate, And a second electrode formed on the spacer and covering the lower substrate and a second electrode coated on at least a part of the lower surface of the upper substrate, .

Also, Japanese Patent Application Laid-Open No. 2009-0002980 discloses a micro fluid flow path including minute particles; An electrode that forms an electric field to move the microparticles by dielectrophoresis with a voltage applied from a voltage source; And an insulator structure configured to deform the electric field to concentrate the fine particles by positive dielectrophoresis; And a microparticle treatment apparatus comprising the microparticle treatment apparatus.

As described above, a device for separating particles based on dielectrophoresis generally has a structure in which alternating voltage is applied to interdigitated electrodes (IDE) at the bottom of channels to separate or collect the particles passing through the channels according to the electrical properties of the particles , It is widely used for the separation and collection of fine particles.

However, in the separation apparatus according to the above method, when the flow velocity is small, the separation performance of the particles is excellent, but when the flow velocity is high, the inertial force due to the flow is larger than the electric force on the particles, Patent Application No. 2014-0029285.

The above patent discloses that a partition wall is provided on a sidewall of a channel formed in the inner side to exhibit a collecting efficiency similar to that of a conventional one at a low flow rate and to reduce the inertial force of particles by the partition wall when the fluid flow rate increases, It is possible to prevent collection and reduction of particle separation efficiency.

However, the improvement of the separability according to the shape of the electrode is not considered in the conventional method in which a plurality of electrodes are provided perpendicularly in the longitudinal direction of the channel.

DISCLOSURE Technical Problem The present invention has been conceived to overcome the disadvantages of the prior art as described above, and it is an object of the present invention to provide a novel type microelectrode structure capable of achieving optimal separation and collection efficiency in the same channel structure, And to provide an electrode.

According to an aspect of the present invention, there is provided an electrode for a device for separating and collecting particles of a dielectrophoretic based particle formed on an inner surface of a channel formed with a constant cross section, ; A second horizontal electrode spaced apart from the first horizontal electrode by a predetermined distance; A third horizontal electrode spaced apart from the second horizontal electrode by a predetermined distance; A fourth horizontal electrode spaced apart from the third horizontal electrode by a predetermined distance; A fifth horizontal electrode formed at the other end of the channel inner surface in the longitudinal direction and spaced apart from the fourth horizontal electrode by a predetermined distance; A second vertical portion extending from one end of the second horizontal electrode to one end of the inner surface of the channel; A third vertical part formed at both ends of the third horizontal electrode and extending in the other end direction of the inner surface of the channel; And a fourth vertical portion formed at both ends of the fourth horizontal electrode and extending in the other end direction of the inner surface of the channel.

Preferably, the horizontal electrodes are formed to have the same width.

More preferably, the distance between the horizontal electrodes is the same.

More preferably, the width of the vertical part is not more than twice the width of the horizontal electrode and not more than twice the width of the horizontal electrode.

More preferably, the second horizontal electrode surrounds the first horizontal electrode.

More preferably, the center of the third horizontal electrode coincides with the center of the channel surface.

More preferably, the third horizontal electrode surrounds the second horizontal electrode, and the fourth horizontal electrode surrounds the fifth horizontal electrode.

An electrode for a dielectrophoretic-based particle separation and collecting apparatus according to the present invention is an improvement of a generally used linear electrode (IDE), and includes a plurality of unit electrodes arranged in the same direction as a channel length square, And has a vertical part for applying a voltage to the electrodes, thereby providing a higher collection efficiency than the conventional linear electrodes.

FIG. 1 is a view for explaining an installation position of an electrode for a dielectrophoretic-based particle separation and collection device according to the present invention,
Fig. 2 is a configuration diagram of the electrode shown in Fig. 1,
3 is a configuration diagram for explaining the embodiment and the comparative example,
FIG. 4 shows a result of the simulation of FIG. 3,
Fig. 5 shows the results of the collection simulation in Fig. 3,
FIG. 6 is a graph showing the collection efficiency of FIG. 3; FIG.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1, the electrode 100 for a dielectrophoretic-based particle separating and collecting apparatus according to the present invention is formed on a bottom surface 2 of a channel 1 in which a space is formed, The particles contained in the fluid are attached to the surface of the electrode 100 by a dielectrophoretic force generated by a power source applied through the electrode, .

2, the electrode 100 includes a first horizontal electrode 10 formed horizontally at an upper end of a channel bottom surface 2, a first horizontal electrode 10 spaced from the first horizontal electrode 10 by a predetermined distance, A second horizontal electrode 20 formed horizontally and a third horizontal electrode 30 horizontally spaced apart from the second horizontal electrode 20 by a predetermined distance from the third horizontal electrode 30, A fourth horizontal electrode 40 formed horizontally and a fifth horizontal electrode 50 spaced apart from the fourth horizontal electrode 40 by a predetermined distance.

At this time, it is preferable that the electrodes 10, 20, 30, 40, 50 have the same width and are disposed at the same interval.

Since the first horizontal electrode 10 and the fifth horizontal electrode 50 are formed on the side of the bottom surface 2, an external power source can be directly applied to the first horizontal electrode 10 and the fifth horizontal electrode 50.

The third horizontal electrode 30 is horizontally disposed at the center of the channel bottom surface 2 and has two third vertical portions 31 extending downward at both ends thereof.

At this time, the width of the third vertical part 31 is preferably larger than the width of the third horizontal electrode 30, and most preferably, it is twice the width of the third horizontal part 30.

The width of the second vertical portion 21 is greater than the width of the second horizontal electrode 20 in the width direction of the second horizontal electrode 20, Is preferably larger than that, and is also most preferably twice as large.

Meanwhile, the fourth horizontal electrode 40 is also formed with the fourth vertical portion 41 downward at both ends, and the width of the fourth vertical portion 41 is formed in the same relationship with the other vertical portions.

The electrodes 100 for collecting and collecting dielectrophoretic particles according to the present invention are arranged such that the fifth horizontal electrode 50 is horizontally disposed on the lower surface of the bottom surface 2 and the first horizontal electrode 50, Is horizontally disposed on the opposite side of the bottom surface 2 of the fifth horizontal electrode 50 and the fourth horizontal electrode 40 is arranged to surround the fifth horizontal electrode 50, The horizontal electrode 30 is arranged to surround the fourth horizontal electrode 40 at the center of the bottom surface 2 and the second horizontal electrode 20 is arranged to surround the first horizontal electrode 10 .

The vertical portions 21, 31, and 41 may be used as an external power source for generating a dielectrophoretic force.

Although the electrode 100 is described as being formed on the channel bottom surface 2, it may be formed on the other side of the channel 1 if necessary.

Example

Width × height × height of 720 μm × 90 μm × 20 μm, and applied at a flow rate of 2 μl / min, an applied voltage of 1 V _pp , and an applied alternating frequency of 1 MHz.

The shape of the electrode is as shown in FIG. 3 (b), the horizontal electrode is set to 1/2 of the vertical electrode width, and the electrode spacing is the same as the width of the horizontal electrode.

Comparative Example

For the purpose of comparison with the embodiment, a conventional vertical electrode of the type shown in FIG. 3 (a) is formed.

The electrodes were formed in the same manner as in the example, and in particular, the same width as the width of the vertical part of the embodiment was formed, and the interval between the electrodes was made equal to the width of the vertical electrode.

Test Example

Computer simulations were performed on the examples and the comparative examples.

The results are shown in FIG. 4 as the dielectric dynamic force at a height of 10 μm in a particle separator of 20 μm height. 4 (a) is a comparative example and FIG. 4 (b) is an embodiment.

It was confirmed from FIG. 4 that the dielectric dynamic power of Examples is excellent.

In addition, trapping simulation of particles (E. coli) was performed, and the results are shown in FIG.

5 (b) shows higher collection characteristics than the comparative example of FIG. 5 (a).

And an E. coli efficiency graph is shown in FIG. It was also confirmed that the embodiment shows high collection efficiency.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, And all of the various forms of embodiments that can be practiced without departing from the technical spirit.

1: Channel 2: Channel bottom
10: first horizontal electrode 20: second horizontal electrode
21: second vertical part 30: third horizontal electrode
31: third vertical part 40: fourth horizontal electrode
41: fourth vertical part 50: fifth horizontal electrode
100: electrode

Claims

1. An electrode for collecting and collecting dielectrophoretic based particles formed on an inner surface of a channel formed with a constant cross section,
A first horizontal electrode formed at one end of a channel inner surface in a longitudinal direction;
A second horizontal electrode spaced apart from the first horizontal electrode by a predetermined distance;
A third horizontal electrode spaced apart from the second horizontal electrode by a predetermined distance;
A fourth horizontal electrode spaced apart from the third horizontal electrode by a predetermined distance;
A fifth horizontal electrode formed at the other end of the channel inner surface in the longitudinal direction and spaced apart from the fourth horizontal electrode by a predetermined distance;
A second vertical portion extending from one end of the second horizontal electrode to one end of the inner surface of the channel;
A third vertical part formed at both ends of the third horizontal electrode and extending in the other end direction of the inner surface of the channel; And
And a fourth vertical part formed at both ends of the fourth horizontal electrode and extending in the other end direction of the inner surface of the channel.

The electrode of claim 1, wherein the horizontal electrodes are formed to have the same width.

The electrode according to claim 2, wherein the distance between the horizontal electrodes is the same.

4. The electrode according to claim 3, wherein the width of the vertical portion is equal to or more than twice the width of the horizontal electrode and the width of the horizontal electrode.

[6] The electrode according to claim 4, wherein the second horizontal electrode surrounds the first horizontal electrode.

[6] The electrode according to claim 5, wherein the center of the third horizontal electrode coincides with the center of the channel surface.

7. The apparatus of claim 6, wherein the third horizontal electrode is configured to surround the second horizontal electrode, and the fourth horizontal electrode surrounds the fifth horizontal electrode. .