WO2019182186A1

WO2019182186A1 - Vertical nanogap dielectrophoretic electrode, manufacturing method therefor, and particle capture and separation method using same

Info

Publication number: WO2019182186A1
Application number: PCT/KR2018/003920
Authority: WO
Inventors: 유용상; 유의상; 김철기; 이택진; 서민아; 김재헌; 전영민; 이선미
Original assignee: 한국과학기술연구원
Priority date: 2018-03-23
Filing date: 2018-04-03
Publication date: 2019-09-26
Also published as: KR102060099B1; KR20190111462A

Abstract

The present invention relates to a sandwich-shaped wide-area electrode pair for dielectrophoresis, the electrode pair having two electrode surfaces, each of which is a patterned flat surface having a continuous flat surface and a plurality of holes, that are spaced apart by a vertical nanogap formed of an insulator layer having a thickness of tens to hundreds of nm; and a use thereof. A first aspect of the present invention provides a layered structure comprising a first conductor layer, an insulator layer, and a second conductor layer which are sequentially stacked, wherein the insulator layer has a predetermined thickness to be selected within a range of 5 to 1000 nm, and the first conductor layer is continuous, but the insulator layer and the second conductor layer have one or more holes formed into the same pattern.

Description

Vertical Nanogap Dielectrophoretic Electrode, Manufacturing Method thereof and Particle Collection and Separation Method Using the Same

The present invention relates to a sandwich-type dielectric electrophoresis, in which a first electrode surface having a continuous plane and a patterned plane second electrode surface having a plurality of holes are spaced apart by vertical nanogaps formed of an insulator layer of tens to hundreds of nm thick. For large area electrode pairs and their use.

Recently, the development of biotechnology and medical engineering field is actively developing technology based on microelectromechanical systems (MEMS) technology based on nanotechnology and micro-based patterning technology. In particular, the development of in-vehicle biosensors and microcapsules for use as microsurgical instruments, microscopic endoscopes, and drug delivery systems has been used as a major means of system biology along with biotechnology applications. Examples include DNA chips and protein chips for screening and diagnosing genes and proteins, and Lap-on-a-chip, which moves a laboratory into a single chip.

In order to realize such a system, the existing experimental process is a field for researching and developing the foundation and core technologies underlying the commercialization of a micro total analysis system, that is, lab-on-a-chip, through the micro-microfluidics field. Has grown to develop microbial biotechnology diagnostic systems. The micro-analysis system is divided into parts having various functions because chemical and biological experiments and analyzes undergoing various experimental steps and reactions are comprehensively implemented in a single unit provided on one bench. , A microfluidic circuit part, and a controller that plays a key role of controlling the microfluidic circuit part. Therefore, in order to implement a lab-on-a-chip, it is necessary to miniaturize and integrate a single chip so as to make a circuit with microchannels and to continuously perform pretreatment, separation, dilution, mixing, biochemical reaction, and detection of a sample. So far, rather than developing a lab-on-a-chip that integrates all of these functions, we are currently developing a lab-on-a-chip that can perform some functions, or in the bio-fluidic device, which actually performs a specific function. to be. In this case, the role of microfluidics that can transport and separate biomaterials in a fluid or an aqueous solution and purify them is very important.

Currently, the method of separating particles using microfluidics can be largely divided into an active separation method and a passive separation method.

The passive separation method is a method of separating particles using flow energy for supplying a sample without providing energy from the outside, and has an advantage in that fine particles can be separated without additional equipment other than the micro flow path. However, this passive separation method has a problem in that fine microfluidic flow control between sample flow and sheath flow is required to align the initial positions in the microfluid before the particles are separated.

On the other hand, the active separation method is to separate particles using an external energy field such as an electric field, and representative examples include capillary electrophoresis and dielectric electrophoresis separation. Double capillary electrophoresis is mainly used to separate polar substances such as proteins or DNA by size, but requires a high voltage for separation and has a disadvantage in that nonpolar particles such as cells cannot be separated. On the contrary, the method of dielectrophoretic separation has the advantage of separating nonpolar molecules or cells without the pretreatment process by using the difference in the dielectrophoretic force that the particles exposed to the non-uniform electric field depending on the size and type of particles. However, the electrophoretic separation method may cause electrolysis in an electrolyte solution such as a cell medium, and thus, a cell-friendly solution cannot be used as a separation solution. In addition, in the case of a biomaterial such as a cell, the activity of the cell is affected by an applied voltage, so there may be a restriction when a separate harvest is used for the purpose of cell therapy.

The present inventors have diligently researched to find a method and apparatus capable of capturing and / or isolating biomaterials such as cells by applying genetic electrophoresis without damaging the applied external energy. A plurality of holes are composed of another electrode which is electrically spaced through an insulator layer having a nanometer thickness, and includes a patterned array, and the insulator layer is formed by using an electrode pair having holes having the same pattern as the electrode. When an alternating voltage is applied to these electrode pairs, a low voltage, that is, exhibits a dielectrophoretic effect without generating heat, thereby adjusting the frequency of alternating current applied thereto, thereby controlling the behavior of the particles contained in the fluid in contact with the electrode pair. It was confirmed that the present invention can be collected or dispersed within, and completed the present invention.

A first aspect of the invention is a first conductor layer sequentially stacked; Insulator layer; And a second conductor layer, wherein the insulator layer has a constant thickness selected from a range of 5 to 1000 nm, and the first conductor layer is continuous, but the insulator layer and the second conductor layer have the same pattern. It provides a layered structure having one or more holes formed into.

A second aspect of the present invention is the first conductor electrode sequentially stacked; Insulator layer; And a second conductor electrode, wherein the pair of dielectric electrophoretic electrodes has holes selectively formed in one electrode, wherein the insulator layer has a constant thickness selected from 5 to 1000 nm, and the first conductor electrode is continuous, The insulator layer and the second conductor electrode provide a dielectrophoretic electrode pair having one or more holes formed in the same pattern.

A third aspect of the invention provides a first method for preparing a layered structure comprising a first conductor layer, an insulator layer having a constant thickness selected from 5 to 1000 nm, a second conductor layer, and a photosensitive resin layer in which a desired pattern is designed. step; A second step of selectively etching the insulator layer, the second conductor layer, and the photosensitive resin layer by etching according to the designed pattern; And a third step of removing the remaining photosensitive resin layer, the method of producing a layered structure having a hole of the first aspect.

A fourth aspect of the present invention provides a method for preparing a layered structure including a first conductor layer, an insulator layer having a constant thickness selected from 5 to 1000 nm, and a photosensitive resin layer in which a pattern is designed; Forming a second conductor layer on the layered structure to be spaced apart from the first conductor layer by an insulator layer and a photosensitive resin layer; The remaining photosensitive resin layer is removed together with the second conductor layer formed on the top thereof, so that the second conductor formed in a pattern opposite to the pattern of the photosensitive resin layer on the layered structure in which the first conductor layer and the insulator layer are sequentially stacked. A third step of forming a structure to which a conductor layer is added; And a fourth step of selectively etching the insulator layer to have the same pattern as the second conductor layer by etching, wherein the layered structure of the first step has a layered structure. Is laminated in the order of the first conductor layer, the insulator layer, and the photosensitive resin layer, or in the order of the first conductor layer, the photosensitive resin layer, and the insulator layer.

The fifth aspect of the present invention includes a circuit in which the electrophoretic electrode pair according to the second aspect having a hole selectively formed in one electrode is electrically connected with an AC power supply, and the electrode surface on which the hole of the dielectric electrophoretic electrode pair is formed is Provided are methods for capturing specific particles in a fluid, using devices designed to be in contact with a fluid containing a sample.

The sixth aspect of the present invention includes a circuit in which the electrophoretic electrode pair according to the second aspect having a hole selectively formed in one electrode is electrically connected with an AC power supply, and the electrode surface on which the hole of the dielectric electrophoretic electrode pair is formed is Provided is a method for separating certain particles from a mixture comprising several particles in a fluid using an apparatus designed to be in contact with a fluid containing a sample.

The present invention has a series of patterned holes selectively formed in one electrode, and provides electrode pairs spaced by vertical nanogaps formed by an insulator layer, thus exhibiting a dielectrophoretic effect simultaneously in the formed plurality of holes. Since the particles of the nature can be selectively collected, it can be usefully applied to recover only the desired particles from the mixture of fine particles or to selectively remove specific particles based on this phenomenon. In addition, this phenomenon can be implemented at low voltage, and thus does not generate heat, thereby extending its application to biomaterials.

1 is a diagram schematically illustrating the principle of trapping particles by dielectrophoresis using a patterned vertical nanogap electrode according to the present invention.

Figure 2 shows the force the particles receive under (left) uniform and (right) uneven electric field gradients, respectively.

3 is a schematic view showing electrode pairs (patterned gold and ITO) spaced with SiO ₂ as a conductor layer according to the present invention and a method of manufacturing the same.

Figure 4 is a vertical nanostructure consisting of ITO electrodes and gold and gold electrodes containing holes formed in patterns of various sizes, separated by a 100 nm thick SiO ₂ layer, made of a large area of several tens of mm ² using the method of the present invention. The figure which shows the shape and cross section of a gap electrode observed with the naked eye and a scanning electron microscope (SEM).

FIG. 5 schematically illustrates (A) an electrode pair (patterned gold and ITO) spaced with PVP as a conductor layer according to an embodiment of the present invention and a method of manufacturing the same, (B) a real vertical nanogap electrode manufactured accordingly The figure which showed the result of observing the form and cross section of with naked eye and SEM.

6 shows simulations of (A) electric field distribution in an electrode pair (patterned gold and ITO) spaced with PVP as a conductor layer according to one embodiment of the present invention, and (B) polystyrene particles having a diameter of 1 μm. Fig. 14 shows the Clausius-Mossotti curve with frequency.

FIG. 7 repeatedly shows the collection and dispersion of particles by applying an alternating voltage of 100 mV while changing the frequency to 10 MHz and 100 KHz selected in the positive and negative regions of the Klausius-Mossito of the calculated curve, respectively. The results are shown.

8 shows the dispersion of particles by applying an alternating voltage of 100 mV while changing the frequency to (A) 100 KHz and (B) 1 MHz selected in the positive and negative regions of the Klausius-Mossotti value of the calculated curve, respectively. It is a figure which shows the result which induced collection.

9 is a diameter of a patterned gold-ITO electrode spaced by a 100 nm thick SiO ₂ layer in accordance with an embodiment of the present invention by applying an alternating current voltage of a frequency corresponding to a positive dielectrophoretic force SEM shows the process of collecting the polystyrene particles of 1 ㎛ size.

FIG. 10 is a view showing the collection of anthracnose microbe (Bacilus Subtilis) which is a biomaterial using a patterned gold-ITO electrode according to an embodiment of the present invention.

Hereinafter, the present invention will be described in more detail.

The present invention requires high voltage to capture and / or separate particles by using the principle of electrophoresis, which requires a high voltage in order to exert the effects of conventional electrophoresis, thereby resulting in electrolysis of the electrolyte, which occurs in the reaction system using the high voltage. Separation was possible when applied to biomaterials due to protein denaturation and / or cell damage due to heat. However, in order to overcome the disadvantage that recovery and use for the original purpose are limited, excellent genophoretic effect is obtained even when a low voltage is applied. It is based on developing an electrode structure that can be exerted. Specifically, an electrode composed of two conductor films is formed, and both electrodes are electrically separated from each other by an insulator layer having a thickness of several tens to hundreds of nanometers, and holes of the same pattern are formed on only one electrode surface and the corresponding insulator layer. By designing an electrode pair in which an array is formed, it is possible to generate a dielectric phenomenon in each hole when an alternating voltage is applied to both electrodes, and even if a low voltage of sub V is applied, the frequency is properly adjusted to achieve a micron level. It is a feature of the present invention that the behavior of the particles can be controlled, for example captured in the holes or dispersed into the fluid.

The present invention sequentially stacked first conductor layer; Insulator layer; And a second conductor layer, wherein the insulator layer has a constant thickness selected from a range of 5 to 1000 nm, and the first conductor layer is continuous, but the insulator layer and the second conductor layer have the same pattern. It is possible to provide a layered structure having one or more holes formed.

Specifically, the layered structure may be manufactured in a large area of several cm ² or more, and includes holes formed from a few to several hundreds to millions or more by adjusting the size of the holes and the spacing between the holes included therein. By using this, it is possible to control the large-capacity biomaterial with an even and / or uniform force.

For example, the holes may each independently have an area of 50 nm ² to 10,000 μm ² , but are not limited thereto. The hole may be circular, but is not limited thereto. For example, the holes may be formed in various forms that can be achieved using nanofabrication technology known in the art.

The formation of the “same pattern” may mean that the shape and the size of the hole of the insulator layer at the second conductor layer and the corresponding position are the same, but do not mean that the shape and size of the entire hole are the same. . For example, one or more holes in one layered structure may each independently have the same or different shape and / or size from each other.

The first conductor layer and the second conductor layer may be films of the same or different conductive materials.

The layered structure of the present invention is a sandwich-type structure in which an electrically conductive first conductor layer and a second conductor layer are spaced apart from an insulator layer having a predetermined thickness, and the first conductor layer and the first conductor layer are formed through the insulator layer. The biconductor layer can act as an electrically separated parallel electrode.

Accordingly, the present invention is a first conductor electrode sequentially stacked; Insulator layer; And a second conductor electrode, wherein the pair of dielectric electrophoretic electrodes has holes selectively formed in one electrode, wherein the insulator layer has a constant thickness selected from 5 to 1000 nm, and the first conductor electrode is continuous, The insulator layer and the second conductor electrode provide a dielectrophoretic electrode pair having one or more holes formed in the same pattern.

As used herein, the term “dielectrophoresis (DEP)” refers to a phenomenon in which a force is applied to a dielectric particle when placed in a non-uniform electric field. It does not require the charging of silver particles, and all particles can exhibit electrophoretic activity in the presence of an electric field. In this case, the strength of the applied force, that is, the force of dielectrophoresis (F _DEP ), depends on the frequency of the electric field as well as the electrical properties of the medium in which the particles are contained and the particles themselves, and the shape and size of the particles. Thus, an electric field of a particular frequency can be used to control the particles, such as controlling the orientation and / or behavior of the particles. The principle of the electrophoresis is shown schematically in FIG.

In theory, the electrophoresis can be expressed by the following equation: the electrophoretic force F _DEP received when a particle is placed in a medium to which an alternating frequency of ω is applied, for example, a fluid.

Where ω is the frequency of alternating current applied to the pair of electrophoretic electrodes, ε _m is the permittivity of the fluid (medium) surrounding the particles, R is the radius of the particles, E is the magnitude of the electric field, and Re (f _CM (ω) ) Is the real part of the Clausius-Mossotti (CM) function for the frequency of the alternating current applied. In the above equation, the factor that determines the sign of the dielectrophoretic force applied to the particles is the real part of the Clausius-Mossotti (CM) function, which can be calculated by the following equation.

Where ω is the frequency of alternating current applied to the dielectric electrophoretic electrode pair, ε ^* _p is the permittivity of the particles to be collected, and ε ^* _m is the permittivity of the fluid.

This is because if the dielectric constant of the particle under the alternating frequency, ω is greater than the dielectric constant of the medium, it will have a positive Klausius-Mossottie value, i.e. Re [f _CM ]> 0, DEP at this time is called positive DEP, In this state, the particles move toward a larger gradient of the electric field. Conversely, if the dielectric constant of the particle is smaller than the dielectric constant of the medium, it has a negative Klausius-Mossottie value, that is, Re [f _CM ] <0, DEP at this time is called negative DEP, and in this state Will move toward the less gradient of the electric field.

For example, the first conductor electrode and the second conductor electrode may each independently be selected from the group consisting of copper, gold, silver, platinum, and palladium; One or more metals selected from the group consisting of copper, gold, silver, platinum and palladium and graphite, tellurium, tungsten, zinc, iridium, ruthenium, arsenic ( alloys or composites containing at least one material selected from the group consisting of arsenic, phosphorus, aluminum, manganese, silicon; Conductive carbon materials selected from the group consisting of graphite, graphene and derivatives thereof; Or a mixed metal oxide selected from the group consisting of indium tin oxide (ITO), titanium oxide (TiO ₂ ), ruthenium oxide (RuO ₂ ), iridium oxide (IrO ₂ ), and platinum oxide (PtO ₂ ) mixed metal oxides), but may be in the form of a film, but is not limited thereto.

The insulator layer may be formed using any non-conductive material having insulating properties without limitation. For example, the insulator layer may be formed of a metal oxide such as SiO ₂ , Nb ₂ O ₅ , TiO ₂ , Al ₂ O ₃ , or MgO, or a polymer such as polyvinylpyrrolidone (PVP), but is not limited thereto. It doesn't work. The type of material and the thickness of the layer to be formed are not limited as long as it can be formed to a uniform thickness at a desired level. However, due to the morphological characteristics of the electrode pair of the present invention, selective etching of the insulator layer is required in the manufacturing process, so that the material of the insulator layer is selected according to the process to be used, or conversely, a specific material is used as the material of the insulator layer. If you choose to design the manufacturing process accordingly. For example, in the case of including the polymer film as the insulator layer, a pattern may be easily etched by treating with a corrosive agent selected according to the type of polymer, for example, a specific solvent.

When the thickness of the insulator layer is less than 5 nm, the layered structure is formed by a 'tunneling effect' in which electrons are transferred regardless of the presence or absence of an insulator due to a distance between the first conductor and the second conductor located on both sides thereof. The whole behaves like one conductor, and the first conductor layer and the second conductor layer are no longer capable of acting as separate electrodes. Thus, the thickness of the insulating layer is determined as the minimum thickness according to the characteristics of the insulator layer which does not allow the tunneling effect, which may be different depending on the material of each electrode and the insulator layer selected. On the other hand, when the thickness of the insulator layer reaches the micrometer level beyond the nano level, for example, when the thickness of the insulator layer exceeds 1000 nm, the available voltage required for effective particle capture becomes large, thereby causing bubbles or reaction systems in the fluid. Excessive heat generation of can cause significant reductions in the effects of electrophoresis and efficiency and / or sensitivity. As described above, the electrophoretic effect is a phenomenon caused by an uneven electric field, and the electrode pair of the present invention has one electrode in a continuous plane and the other in which holes are spaced in parallel with each other by an insulator layer of nm level. Considering that the electrode exhibits dielectric effect due to non-uniform electric field formed by opposing electrodes of different types, the increase in the thickness of the insulating layer results in relatively small defects caused by holes. May lead to a decrease. Therefore, it will be apparent to those skilled in the art that the thickness of the insulator layer and / or the size of the holes can be controlled organically in consideration of the size of particles to be collected or dispersed therein.

The layered structure and the electrophoretic electrode pair according to the present invention is a layer comprising a first conductor layer, an insulator layer having a constant thickness selected from a range of 5 to 1000 nm, a second conductor layer, and a photosensitive resin layer in which a desired pattern is designed. A first step of preparing a pictograph structure; A second step of selectively etching the insulator layer, the second conductor layer, and the photosensitive resin layer by etching according to the designed pattern; And it may be prepared through a process comprising a third step of removing the remaining photosensitive resin layer. For example, the manufacturing method may be performed by combining the lamination and etching methods of various materials known in the art. The specific method of performing each step may be selected according to the material of each selected layer.

For example, etching by etching may be performed using dry and / or wet etching methods. When each component layer is formed of a known material and thickness, a dry etching method may be selected, and the execution time may be determined in consideration of the etching rate of each layer according to the selected method. On the other hand, when the insulator layer includes a polymer film such as PVP, a wet etching method may be selected in consideration of the fact that only the polymer film can be selectively removed by a simple method of treating with a specific solvent. Alternatively, if necessary, the second conductor layer may be a dry etching method and a complex method of etching the insulator layer by a wet etching method, but is not limited thereto. The etching method may be selected in consideration of the material of each constituent layer, an etching method known in the art, and / or a convenience and economy of performing the process.

In addition, another method for manufacturing a layered structure and a dielectric electrophoretic electrode pair according to the present invention is a layer comprising a first conductor layer, an insulator layer of a constant thickness selected from the range of 5 to 1000 nm, and a photosensitive resin layer devised pattern A first step of preparing a pictograph structure; Forming a second conductor layer on the layered structure to be spaced apart from the first conductor layer by an insulator layer and a photosensitive resin layer; And removing the remaining photosensitive resin layer together with the second conductor layer formed on the upper side thereof, and forming the first conductor layer and the insulator layer on the layered structure in which the first conductor layer and the insulator layer are sequentially stacked in a pattern opposite to the pattern of the photosensitive resin layer. The second conductor layer may include a third step of forming a structure to which the conductor is added. In this case, the layered structure of the first step may be stacked in order of the first conductor layer, the insulator layer, and the photosensitive resin layer, or in the order of the first conductor layer, the photosensitive resin layer, and the insulator layer.

In the manufacturing method, when using a layered structure stacked in the order of the first conductor layer, the insulator layer, and the photosensitive resin layer in the first step, the same pattern as the second conductor layer by etching after the third step A fourth step of selectively etching the insulator layer may be further included. In the etching process, the patterned second conductor layer formed on the insulator layer may serve as a mask. The fourth step may be performed using a dry or wet etching method known in the art.

As described above, according to the present invention, the electrophoretic electrode pair having a hole selectively formed on one electrode can control the movement of particles introduced thereto by the electrophoretic effect, so that the pair of electrodes together with the AC power supply unit It can be used to capture specific particles in a fluid using a device having an electrically connected circuit and designed to contact the fluid containing the sample with the electrode surface on which the hole of the pair of dielectric electrophoretic electrodes is formed.

Specifically, the collection of the particles is a first step of deriving a Clausius-Mossotti (CM) curve for the particles to be collected using the following equation 1 according to the applied alternating frequency; And a second step of applying an alternating current of a frequency selected from a range in which the real part of Klausius-Mossotti represents a positive value in the curve derived from the first step:

Equation 1

In the above equation,

ω is the frequency of alternating current applied to the

ε ^* _p is the permittivity of the particle

ε ^* _m is the permittivity of the fluid.

In addition, the electrophoretic electrode pair having a hole selectively formed in one electrode according to the present invention, the circuit having an electrically connected with the AC power supply, the electrode surface on which the hole of the dielectric electrophoretic electrode pair is formed includes a sample. Using a device designed to be in contact with a fluid, in a similar principle to the particle capture method described above, it can be used to separate certain particles from a mixture comprising N kinds of particles in a fluid (N is two or more natural waters).

Specifically, a first step of deriving the Clausius-Mossotti curve according to the frequency of the individual particles to be separated using the following equation 1-1; From the curve derived from the first step, the frequency of the real part of Klausius-Mossotti shows a positive or negative value for some particle (s) and vice versa for other particle (s) to be separated from it. Selecting a second step; And a third step of applying alternating current of the frequency selected from the second step:

Equation 1-1

In the above equation,

ω is the frequency of alternating current applied to the

n is an arbitrary number identifying the type of particles, where 1≤n≤N, a natural number,

ε ^* _pn is the permittivity of particle n,

ε ^* _m is the permittivity of the fluid.

Particles that can be collected and / or separated by the method of the present invention may be, but are not limited to, viruses, microorganisms, and the like, having a submicrometer to several micrometer diameter. Based on this, the collection and / or separation methods of the present invention can be used to detect the presence of bacteria or microorganisms in a fluid, for example, or to remove these substances from a fluid in which the presence of bacteria or microorganisms has been confirmed.

Further, the particle separation method of the present invention may be performed by repeating the second step and the third step one or more times with respect to the particle (s) collected or excluded in the third step, but is not limited thereto.

The repeated steps in the particle separation method of the present invention may be performed by changing the frequency of alternating current applied, but may be performed continuously using the same device used for the primary separation, or using the same device connected in parallel thereto. For example, in the case where two or more kinds of particles, including particles of interest, remain in the holes after separation of the primary particles, and the particles of interest are to be separated from these particles, the fluid except for the particles collected in the holes after the primary separation After removing the dispersed particles within, fill the fresh fluid of the same permittivity and apply alternating frequency of alternating frequency to the same device as in the primary separation, or fill the fluid with a different permittivity as in the primary separation and repeat the separation while maintaining the frequency Can be done. Or when the particles of interest to be separated are not collected in holes in the primary separation and are dispersed together with other particles in the fluid, the fluid containing the particles of interest in a novel separation device having the electrophoretic electrode pairs of the invention connected thereto. It may be repeated to separate the mixed particles in the same manner by transmitting the and applying a changed frequency in the novel separation device.

In a specific embodiment of the present invention, a device including the electrode pair of the present invention and designed to apply an alternating current power is contacted with a fluid containing polystyrene particles having a diameter of about 1 μm and having a size similar to that of a virus and varying frequencies. It was confirmed that the particles could be collected or dispersed at a low voltage of 100 mV by applying an alternating voltage of (FIGS. 7 to 9). Furthermore, it was confirmed that it can be applied to anthrax mimetics which are biomaterials, for example, Bacillus subtilis, to collect them (FIG. 10). This indicates that the electrode pair of the present invention can be applied to a device for collecting viruses of similar size by the electrophoretic effect. Furthermore, considering that ultrafine dust, which is of great interest recently, is larger than 2.5 μm particles, the electrode pair of the present invention may be applied to a (ultra) fine dust collection and / or removal device that can be driven at low voltage.

Hereinafter, the present invention will be described in more detail with reference to Examples. These examples are intended to illustrate the present invention more specifically, but the scope of the present invention is not limited by these examples.

실시예Example 1: 일면에 패턴화된 홀을 갖고 양면이 1: with patterned holes on one side SiOSiO ₂₂ 로in 이격된Spaced 대면적 수직 Large area vertical 나노갭Nanogap 어레이의 제조 Fabrication of Array

A 100 nm thick ITO layer was formed on a glass substrate patterned with a 1 cm × 1 cm area with a 4 mm × 3 mm area, and then SiO _{2 at} 100 nm thickness using a plasma-enhanced chemical vapor deposition (PECVD) apparatus. The layer was deposited. Thereafter, a 100 nm thick gold layer was formed on the SiO ₂ layer by thermal evaporation. Subsequently, the photosensitive resin (AZ152, Microchemical) was spin coated and heated to form a photosensitive resin layer. On the surface on which the photosensitive resin layer was formed, a photomask having an array-shaped pattern in which a series of holes having a diameter of 30 μm was arranged at intervals of 30 μm was placed, and irradiated with ultraviolet rays on the photomask to develop and remove the masked portion. . As described above, the second conductor layer and the insulator layer exposed to the lower end of the hole pattern by performing inductively coupled plasma (ICP) etching on the layered structure in which the hole array pattern is formed of the photosensitive resin are formed in the same form as the pattern. Etched. The etching rate during etching through the ICP etching is different from the gold constituting the second conductor layer and SiO ₂ constituting the insulator layer, so that the first insulator layer is maintained but the second conductor layer and the insulator layer can be selectively removed. In addition, the processing time was calculated in consideration of the thickness of each of these layers and the etching rate for the corresponding material. Specifically, in the case of SiO ₂ etching by ICP etching, etching was performed at about 230 nm / sec at 5 mTorr pressure with ICP 2700 W and a bias of 75 W at 4 mTorr pressure under 15 sccm of argon gas and 90 sccm of CHF ₃ gas. . On the other hand, in the case of the gold layer, under 8 sccm of argon gas and 4 sccm of Cl ₂ gas, ICP 1000 W at 0.5 Torr pressure and 150 W bias were etched under helium 5 mTorr pressure at about 130 nm / sec.

실시예Example 2: 일면에 패턴화된 홀을 갖고 양면이 2: with patterned holes on one side PVP로With PVP 이격된Spaced 대면적 수직 Large area vertical 나노갭Nanogap 어레이의 제조 Fabrication of Array

A 180 nm thick ITO layer was spin-coated and heated a polyvinylphenol (PVP) solution on a glass substrate patterned with a 1 cm × 1 cm area to form a 110 nm thick insulator layer of PVP. Subsequently, the photosensitive resin (AZ1512) was spin-coated and heated on the PVP layer to form a photosensitive resin layer. On the surface on which the photosensitive resin layer was formed, a photomask having an array-shaped pattern in which a series of holes having a diameter of 30 μm was arranged at intervals of 30 μm was placed, and irradiated with ultraviolet rays on the photomask to develop and remove the masked portion. . A 120 nm thick gold thin film was formed on the patterned surface on the laminate structure including the patterned photosensitive resin layer by thermal deposition. Thereafter, the film was treated with acetone to remove the residual photosensitive resin pattern and the unnecessary gold thin film formed on the surface thereof, thereby obtaining a gold thin film layer having a hole array pattern. Furthermore, the hole portion not covered by the patterned gold thin film was used as a mask by treating it at 150 W for 2 minutes and 15 seconds through reactive ion etching using oxygen gas at a flow rate of 100 sccm at 100 mTorr pressure. Part of the PVP insulator layer exposed to was selectively removed.

실험예 1: 수직 나노갭 어레이의 형상 분석Experimental Example 1: Shape Analysis of Vertical Nanogap Array

According to Examples 1 and 2, one electrode, which is spaced apart by an insulator nanogap made of several mm ² and several cm ² , respectively, is formed continuously and another electrode having a plurality of hole array patterns is formed. The manufacturing process of the electrode pair including the schematic shown in Figures 3 and 5A. In addition, the appearance of the electrode pairs thus prepared was visually observed, and the fine hole array pattern and the cross section were confirmed by SEM, and the results are shown in FIGS. 4 and 5B.

실험예 2: 유전영동법을 이용한 폴리스티렌 비드의 포집 및 분산Experimental Example 2: Collection and Dispersion of Polystyrene Beads Using Genetic Electrophoresis

In the present invention, the use of polystyrene (PS) particles having a diameter and a diameter of 1 μm similar to those of the virus particles, the possibility of application in the detection of biological substances such as viruses of the electrode pair prepared according to Examples 1 and 2 above. Confirmed.

First, before the actual experiment, the genetic phenomena were predicted through simulation. The force acting on the particle by the electrophoretic phenomenon is determined by the conductivity of the material surrounding the particle, the permittivity and the frequency of the applied alternating voltage, which can be calculated according to the following equation.

Where ω is the frequency of alternating current applied to the pair of dielectrophoretic electrodes, ε _m is the permittivity of the fluid surrounding the particles, R is the radius of the particles used, E is the magnitude of the electric field, and Re (f _CM (ω)) is applied. It is the real part of the Clausius-Mossotti (CM) function for the frequency of the alternating current. In the above equation, the factor that determines the sign of the dielectrophoretic force applied to the particles is the real part of the Clausius-Mossotti (CM) function, which can be calculated by the following equation.

Where ω is the frequency of alternating current applied to the dielectric electrophoretic electrode pair, ε ^* _p is the permittivity of the particles to be collected, and ε ^* _m is the permittivity of the fluid. The distribution of the electric field generated when an alternating voltage is applied to the electrophoretic electrode pairs prepared according to Examples 1 and 2 according to the frequency for the polystyrene particles theoretically derived through the above formula is shown in FIG. The Klausius-Mossotti function is shown in Figure 6 (B). Furthermore, an alternating frequency dependent Klausius-Mossoti graph for polystyrene particles upon alternating voltage is shown in FIG. 8 (B). As shown in FIG. 6 (B), the Klausius-Mossottie value for the polystyrene particles was found to change its characteristics on the basis of 1 MHz, specifically, a positive value at a frequency below 1 MHz, Negative values were shown at frequencies above 1 MHz.

From the graph of FIG. 6 (B), when the dielectric force applied to the particles when the AC voltage is calculated through the two equations is combined with the movement of the particles, the particles subjected to positive dielectric force move toward the electrode. On the other hand, the negatively electrophoretic particles were expected to move in the direction of the electrode.

In order to confirm whether the result predicted by the theoretical calculation can be implemented using the electrophoretic electrode pair of the present invention, the hole array pattern of the electrode pairs prepared according to Examples 1 and 2 has a diameter of 1 μm. The device is configured to be in contact with a fluid containing polystyrene particles (tertiary distilled water of 18.2 MΩ or more), and an AC power source is connected to both electrically connected electrodes to induce dielectric phenomena. It was confirmed by taking a video. Specifically, a voltage of 100 mV is applied to a device having an electrode pair manufactured according to Example 1 while changing the frequency to 100 kHz and 10 MHz, and a low voltage of 0.1 V is applied to the electrode pair prepared according to Example 2. The behavior of the particles was measured by applying alternating current at 100 kHz and 1 MHz frequencies, and the results are shown in FIGS. 7 and 8, respectively.

As shown in FIG. 7, when an alternating current of 100 kHz having a positive Klausius-Mossottie value is applied, the particles are collected in the hole under the electrophoretic force toward the electrode, and the edge of the hole is adjacent to the electrode. When alternating current is applied, a 10 MHz alternating current with negative Klausius-Mossoti values is applied, which tends to disperse the particles out of the hole or toward the center of the hole away from the electrode. It was observed repeatedly as the frequency was changed. In addition, as shown in FIG. 8, even in the electrode pair prepared according to Example 2, when an alternating current of 100 kHz having a positive Klausius-Mossett value is applied, the particles move toward the electrode. That is, the particles tended to disperse when an alternating current of 1 MHz, which is arranged at the boundary of the hole and collected in the hole, has a Clausius-Mossottie value close to zero. This indicates that the electrode pairs prepared according to the present invention are capable of capturing particles by dielectric kinetic force at low voltage, and furthermore, by virtue of this principle, can separate specific particles from mixtures of particles of different sizes and / or permittivity.

실험예 3: 유전영동법을 이용한 박테리아의 포집Experimental Example 3 Collection of Bacteria Using Genetics

In order to confirm that the electrode pairs of the present invention can be applied to the collection of biomaterials using dielectric electrophoresis, a sample containing Bacillus subtilis, an anthrax mimic, instead of polystyrene particles was tested in a similar manner to the above experimental example. It was.

Specifically, a Bacillus subtilis spore incubated for 16 to 20 hours at 37 ° C. was contacted with a device having a gold-ITO electrode pair having a hole array having a diameter of 10 μm, and a 3 V alternating voltage at a frequency of 100 kHz. Was applied, and it was confirmed by SEM that bacteria were collected in the electrode hole, and the results are shown in FIG. 10. As shown in FIG. 10, when the AC voltage was applied, the Bacillus subtilis was collected on the electrode and arranged along the boundary of the patterned hole. This indicates that the electrophoresis using the electrode pair of the present invention enables the capture and / or separation of actual biomaterials such as bacteria present in the fluid.

Claims

A first conductor layer sequentially stacked; Insulator layer; And a second conductor layer, comprising:

The insulator layer has a constant thickness selected from 5 to 1000 nm,

Wherein the first conductor layer is continuous, but the insulator layer and the second conductor layer have one or more holes formed in the same pattern.
The method of claim 1,

The holes are each independently a layered structure having an area of 50 nm 2 to 10,000 μm 2 .
A first conductor electrode sequentially stacked; Insulator layer; And a second conductor electrode, comprising: a pair of dielectric electrophoretic electrodes having holes selectively formed in one electrode;

The insulator layer has a constant thickness selected from 5 to 1000 nm,

Wherein the first conductor electrode is continuous, but the insulator layer and the second conductor electrode have one or more holes formed in the same pattern.
The method of claim 3,

The first conductor electrode and the second conductor electrode are each independently selected from the group consisting of copper, gold, silver, platinum, and palladium; One or more metals selected from the group consisting of copper, gold, silver, platinum and palladium and graphite, tellurium, tungsten, zinc, iridium, ruthenium, arsenic ( alloys or composites containing at least one material selected from the group consisting of arsenic, phosphorus, aluminum, manganese, silicon; Conductive carbon materials selected from the group consisting of graphite, graphene and derivatives thereof; Or a mixed metal oxide selected from the group consisting of indium tin oxide (ITO), titanium oxide (TiO 2 ), ruthenium oxide (RuO 2 ), iridium oxide (IrO 2 ), and platinum oxide (PtO 2 ) Dielectrophoretic electrode pairs that are made of mixed metal oxides).
The method of claim 3,

The insulator layer is a dielectrophoretic electrode pair of a material selected from the group consisting of SiO 2 , polyvinylpyrrolidone (PVP), Nb 2 O 5 , TiO 2 , Al 2 O 3 , and MgO.
A first step of preparing a layered structure including a first conductor layer, an insulator layer having a constant thickness selected from a range of 5 to 1000 nm, a second conductor layer, and a photosensitive resin layer having a desired pattern;

A second step of selectively etching the insulator layer, the second conductor layer, and the photosensitive resin layer by etching according to the designed pattern; And

A method of manufacturing a layered structure having the hole of claim 1, comprising a third step of removing the remaining photosensitive resin layer.
A first step of preparing a layered structure including a first conductor layer, an insulator layer having a constant thickness selected from 5 to 1000 nm, and a photosensitive resin layer devised pattern;

Forming a second conductor layer on the layered structure to be spaced apart from the first conductor layer by an insulator layer and a photosensitive resin layer;

The remaining photosensitive resin layer is removed together with the second conductor layer formed on the top thereof, so that the second conductor formed in a pattern opposite to the pattern of the photosensitive resin layer on the layered structure in which the first conductor layer and the insulator layer are sequentially stacked. A third step of forming a structure in which a conductor layer is added; And

A method of manufacturing a layered structure having a hole according to claim 1, comprising a fourth step of selectively etching the insulator layer to have the same pattern as the second conductor layer by etching.

The layered structure of the first step is laminated in the order of the first conductor layer, the insulator layer, and the photosensitive resin layer, or in the order of the first conductor layer, the photosensitive resin layer, and the insulator layer.
The dielectric electrophoretic electrode pair of claim 3 having a hole selectively formed in one electrode has a circuit electrically connected with an AC power supply, and the electrode surface on which the hole of the dielectric electrophoretic electrode pair is formed is in contact with a fluid including a sample. A method of capturing specific particles in a fluid using an apparatus.
The method of claim 8,

A first step of deriving a Clausius-Mossotti (CM) curve according to an applied alternating frequency for particles to be collected using Equation 1 below; And

A method for collecting particles, the method comprising: a second step of applying an alternating current of a frequency selected from a range in which the real part of Klausius-Mossotti represents a positive value in the curve derived from the first step:

Equation 1

In the above equation,

ω is the frequency of alternating current applied to the

ε * p is the permittivity of the particle

ε * m is the permittivity of the fluid.
The dielectric electrophoretic electrode pair of claim 3 having a hole selectively formed in one electrode has a circuit electrically connected with an AC power supply, and the electrode surface on which the hole of the dielectric electrophoretic electrode pair is formed is in contact with a fluid including a sample. Using a device to separate particular particles from a mixture comprising N particles in a fluid, where N is at least two natural waters.
The method of claim 10,

A first step of deriving a Clausius-Mossotti curve according to frequency of individual particles to be separated using Equation 1-1;

From the curve derived from the first step, the frequency of the real part of Klausius-Mossotti shows a positive or negative value for some particle (s) and vice versa for other particle (s) to be separated from it. Selecting a second step; And

Achieved by a method comprising a third step of applying an alternating current of a frequency selected from said second step:

Equation 1-1

In the above equation,

ω is the frequency of alternating current applied to the

n is an arbitrary number identifying the type of particles, where 1≤n≤N, a natural number,

ε * pn is the permittivity of particle n,

ε * m is the permittivity of the fluid.
The method of claim 10,

Particle separation method, wherein the second step and the third step is repeated one or more times for the particle (s) collected or excluded in the third step.
The method of claim 12,

Performing by changing the frequency of the alternating current is applied, it is carried out continuously by using the device used in claim 10, or using the same device connected in parallel.