Microfluidic chip and microfluidic system

Abstract

The application provides a micro-fluidic chip and a micro-fluidic system, and relates to the technical field of control structures.The micro-fluidic chip comprises a top substrate and a bottom substrate, the top substrate and the bottom substrate are oppositely arranged to form a cavity, a conductive layer is arranged on the bottom surface of the top substrate, an electrode layer formed by a plurality of electrodes arranged in sequence is arranged on the top surface of the bottom substrate, and a dielectric layer surrounding the plurality of electrodes is further arranged on the electrode layer; the plurality of first electrodes are used for driving a mother liquid drop to move to a spraying area, and the plurality of second electrodes are used for controlling the mother liquid drop to spray in the spraying area. The top substrate and the bottom substrate are oppositely arranged to form the cavity, the conductive layer is arranged on the bottom surface of the top substrate, the electrode layer is arranged on the top surface of the bottom substrate, and driving voltage is applied to the electrodes to drive the liquid drop to move and spray, thereby improving the convenience of micro-fluid distribution. The electrode layer is formed by the plurality of electrodes arranged in sequence, and the micro-fluid chip also has the characteristics of simple structure.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of control structure, and in particular, to a microfluidic chip and a microfluidic system. BACKGROUND

[0002] In biochemical experiments, it is often necessary to dispense a specific volume of liquid, and microfluidic sample manipulation becomes more challenging. Microfluidic sample dispensing can be performed on a chip, and high-precision microfluidic dispensing is a certain challenge and has become a research hotspot.

[0003] In related technologies, a channel-based microfluidic platform is developed to accurately measure and dispense microfluids. On this platform, external forces such as air pressure are used to force continuous microfluidic flow through a microchannel to achieve microfluidic dispensing.

[0004] However, in related technologies, by forcing continuous microfluidic flow through a microchannel to drive microfluidic movement, complex external devices are required, which is not convenient for microfluidic dispensing. SUMMARY

[0005] The present application aims to solve the above technical problems in related technologies by providing a microfluidic chip and a microfluidic system.

[0006] To achieve the above-mentioned purposes, the technical solutions adopted by the embodiments of the present application are as follows:

[0007] In a first aspect, the embodiments of the present application provide a microfluidic chip, comprising: a top substrate and a bottom substrate, the top substrate and the bottom substrate are oppositely arranged to form a cavity, the bottom surface of the top substrate is provided with a conductive layer, the top surface of the bottom substrate is provided with an electrode layer formed by a plurality of electrodes arranged in sequence, and the electrode layer is further provided with a dielectric layer surrounding the plurality of electrodes;

[0008] The plurality of electrodes comprises a plurality of first electrodes of a first moving area and a plurality of second electrodes of a jetting area in communication with the first moving area; the plurality of first electrodes are used to drive the movement of a mother liquid droplet to the jetting area, and the plurality of second electrodes are used to control the jetting of the mother liquid droplet in the jetting area;

[0009] The plurality of second electrodes comprises a retaining electrode and a jetting electrode, the retaining electrode is an electrode close to the first moving area, and the jetting electrode is an electrode away from the first moving area, and the jetting electrode is provided with a jetting neck on the side facing the retaining electrode;

[0010] The retaining electrode is used for retaining the mother droplet, and the ejection electrode is used for ejecting the mother droplet through the ejection neck and containing the formed satellite droplet.

[0011] Optionally, the retaining electrode is a regular polygon, and the number of edges in the regular polygon is greater than or equal to a preset threshold.

[0012] Optionally, the plurality of first electrodes are a plurality of electrodes of preset geometric shapes.

[0013] Optionally, the arrangement gap of the plurality of first electrodes is smaller than the arrangement gap of the plurality of second electrodes.

[0014] Optionally, the arrangement gap of the plurality of first electrodes is any value in a range from 10 um to 30 um, and the arrangement gap of the plurality of second electrodes is any value in a range from 40 um to 100 um.

[0015] Optionally, the plurality of electrodes further include a plurality of third electrodes in a second moving area, which are arranged in sequence near the ejection electrode; and the third electrodes are used for controlling the target droplet to pick up the satellite droplet in the second moving area.

[0016] Optionally, the dielectric layer is further provided with at least two fourth electrodes belonging to the same plane as the plurality of electrodes and arranged around the retaining electrode and the ejection electrode.

[0017] Optionally, the plurality of electrodes further include a fifth electrode in a droplet containing area, which is in communication with the first moving area, so as to separate a droplet sample in the droplet containing area to generate the mother droplet or to eat back the mother droplet by using the droplet sample.

[0018] In a second aspect, an embodiment of the present application provides a microfluidic system, including a controller, a signal generator, a relay array, and the microfluidic chip according to any one of the first aspect, wherein an input end of the relay array is connected to an output end of the signal generator, a plurality of output ends of the relay array are respectively connected to the plurality of electrodes in the microfluidic chip, and the controller is connected to a control end of the relay array.

[0019] The beneficial effects of the present application are: the microfluidic chip provided by the embodiment of the present application comprises: a top substrate, a bottom substrate, the top substrate and the bottom substrate are oppositely arranged to form a cavity, a conductive layer is arranged on the bottom surface of the top substrate, an electrode layer formed by a plurality of electrodes arranged in sequence is arranged on the top surface of the bottom substrate, and a dielectric layer surrounding the plurality of electrodes is further arranged on the electrode layer; wherein the plurality of electrodes comprise: a plurality of first electrodes of a first moving area, and a plurality of second electrodes of a spraying area in communication with the first moving area; the plurality of first electrodes are used to drive the mother liquid drop to move to the spraying area, and the plurality of second electrodes are used to control the mother liquid drop to spray in the spraying area; the plurality of second electrodes comprise: a retaining electrode and a spraying electrode, the retaining electrode is an electrode close to the first moving area, and the spraying electrode is an electrode away from the first moving area, and a spraying neck is arranged on one side of the spraying electrode facing the retaining electrode; the retaining electrode is used to retain the mother liquid drop, and the spraying electrode is used to make the mother liquid drop spray through the spraying neck and accommodate the formed satellite liquid drop. The top substrate and the bottom substrate are oppositely arranged to form a cavity, a conductive layer is arranged on the bottom surface of the top substrate, and an electrode layer is arranged on the top surface of the bottom substrate. By applying a driving voltage to the electrode, the liquid drop can be driven to move and spray, the convenience of microfluidic distribution is improved, the electrode layer is formed by a plurality of electrodes arranged in sequence, and the microfluidic chip also has the characteristics of simple structure. Moreover, the spraying neck is arranged on one side of the spraying electrode facing the retaining electrode, the spraying neck and the retaining electrode do not overlap, the satellite liquid drop is accommodated on the spraying electrode after spraying, and the calculation of the volume of the satellite liquid drop is facilitated. BRIEF DESCRIPTION OF DRAWINGS

[0020] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments. It should be understood that the following drawings only show some embodiments of the present application, and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can also be obtained without creative labor on the basis of these drawings.

[0021] Figure 1 A structural schematic diagram of a microfluidic chip provided by the embodiment of the present application;

[0022] Figure 2 A structural schematic diagram of an electrode in a microfluidic chip provided by the embodiment of the present application;

[0023] Figure 3 A structural schematic diagram of an electrode in a microfluidic chip provided by the embodiment of the present application;

[0024] Figure 4 A structural schematic diagram of an electrode in a microfluidic chip provided by the embodiment of the present application;

[0025] Figures 5a to 5dA schematic diagram of the principle of mother liquor drop generation provided by the embodiment of the present application is shown in the figure.

[0026] Figure 6 A schematic diagram of the structure of a microfluidic system provided by the embodiment of the present application is shown in the figure. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical scheme and advantages of the embodiment of the present application clearer, the technical scheme in the embodiment of the present application will be described clearly and completely below with reference to the drawings in the embodiment of the present application. Obviously, the described embodiment is a part of the embodiments of the present application, rather than all the embodiments of the present application.

[0028] Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the claimed present application, but only represents selected embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without making creative efforts are within the scope of protection of the present application.

[0029] In the description of the present application, it should be noted that if the terms "upper", "lower", etc. indicate the orientation or position relationship shown in the drawings, or the orientation or position relationship when the product of the present application is used, it is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.

[0030] In addition, the terms "first", "second", etc. in the specification and claims of the present application and the above drawings are used to distinguish similar objects, and do not necessarily indicate a specific order or sequence. It should be understood that the data thus used can be interchanged under appropriate circumstances, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device including a series of steps or units does not have to be limited to only those steps or units clearly listed, but can include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0031] It should be noted that the features in the embodiments of the present application can be combined with each other without conflict.

[0032] In biochemical experiments, it is often necessary to dispense a specific volume of liquid, and microfluidic sample manipulation becomes more challenging. Microfluidic sample dispensing can be performed on a chip, and high-precision microfluidic dispensing is a certain challenge and has become a research hotspot.

[0033] In related technologies, channel-based microfluidic platforms have been developed for the precise measurement and distribution of microfluidics. On these platforms, external forces, such as air pressure, are used to force a continuous flow of microfluidic fluid through microchannels to achieve distribution. However, these technologies, which drive the movement of microfluidics by forcing a continuous flow through microchannels, require complex external devices and are not convenient for microfluidic distribution.

[0034] To address the aforementioned technical problems in related technologies, this application provides a microfluidic chip in which a top substrate and a bottom substrate are disposed opposite each other to form a cavity. A conductive layer is disposed on the bottom surface of the top substrate, and an electrode layer is disposed on the top surface of the bottom substrate. Applying a driving voltage to the electrodes can drive the droplets to move and spray, which improves the convenience of microfluidic distribution. The conductive layer is formed by multiple electrodes arranged in sequence. This microfluidic chip also has the characteristics of simple structure.

[0035] Figure 1 This is a schematic diagram of the structure of a microfluidic chip provided in an embodiment of the present invention, as shown below. Figure 1 As shown, the microfluidic chip may include: a top substrate 101 and a bottom substrate 102. The top substrate 101 and the bottom substrate 102 are disposed opposite each other to form a cavity. A conductive layer 103 is disposed on the bottom surface of the top substrate 101. An electrode layer formed by a plurality of electrodes 104 arranged in sequence is disposed on the top surface of the bottom substrate 102. A dielectric layer 105 surrounding the plurality of electrodes 104 is also disposed on the electrode layer.

[0036] The plurality of electrodes 104 include: a plurality of first electrodes in a first moving region, and a plurality of second electrodes in a spraying region connected to the first moving region; the plurality of first electrodes are used to drive the mother liquor droplets to move to the spraying region, and the plurality of second electrodes are used to control the mother liquor droplets to be sprayed in the spraying region.

[0037] In this embodiment, applying a driving voltage to one of the multiple electrodes 104 drives the droplet to move within the chamber. Applying driving voltages to different electrodes according to actual needs controls the direction and position of the droplet's movement. Specifically, when a driving voltage is applied to an electrode adjacent to the droplet's electrode, the droplet is pulled to the position corresponding to the activated electrode under the influence of wetting force. Based on this principle, the droplet can perform operations such as movement and ejection within a microfluidic chip. For example, energizing the electrode adjacent to the left of the droplet's electrode drives the droplet to move to the left; energizing the electrode adjacent to the right of the droplet's electrode drives the droplet to move to the right.

[0038] Optionally, the conductive layer 103 can be an ITO (indium tin oxide) layer, the dielectric layer 105 can be SU8 (an epoxy type, near ultraviolet negative photoresist), and the thickness of the dielectric layer 105 can be 10 microns (microns), of course, the thickness can be determined according to actual requirements or empirical values. In addition, a plurality of SU8 small square columns can be made on the dielectric layer 105 to prevent the drift of the droplets.

[0039] It is worth noting that the plurality of electrodes 104 are arranged in sequence, the first electrode and the second electrode are part of the plurality of electrodes 104, and the plurality of first electrodes and the plurality of second electrodes are also arranged in sequence, wherein the sequence arrangement means that the plurality of first electrodes and the plurality of second electrodes are arranged in sequence in the same horizontal plane, and there is no embedded or stacked arrangement; of course, the arrangement order of the plurality of first electrodes and the plurality of second electrodes is specifically limited.

[0040] In addition, the microfluidic chip can be referred to as a DMF (digital microfluidics).

[0041] Optionally, Figure 2 A structural diagram of an electrode in a microfluidic chip provided by the embodiment of the present application is shown in FIG. 1. Figure 2 As shown, the plurality of second electrodes includes a retaining electrode 1041 and a jetting electrode 1042, the retaining electrode 1041 is an electrode close to the first moving area, and the jetting electrode 1042 is an electrode away from the first moving area, and the side of the jetting electrode 1042 facing the retaining electrode 1041 is provided with a jetting neck.

[0042] The retaining electrode 1041 is used to retain the mother droplet, and the jetting electrode 1042 is used to make the mother droplet jet through the jetting neck and accommodate the formed satellite droplet.

[0043] It should be noted that in the related art, due to the overlapping part of the electrode, the satellite droplet ejected will exist in the overlapping gap, and generally, a fluorescent substance is added to the mother droplet, and the satellite droplet ejected also contains the fluorescent substance, and the satellite droplet existing in the gap can be easily identified by the fluorescent substance, so as to calculate the volume of all satellite droplets, and the fluorescent substance may affect the microfluid, affecting the biochemical experiment. In the embodiment of the present application, the side of the jetting electrode facing the retaining electrode is provided with a jetting neck, and the jetting electrode and the retaining electrode do not have an overlapping area, and the jetting electrode is an electrode for accommodating the satellite droplet, and in the process of jetting, the jetting voltage of the entire accommodating area drives the satellite droplet to disperse in the accommodating area, so that the satellite droplet after jetting can be accommodated on the jetting electrode, and is not easy to fall between the electrodes, which is beneficial to the calculation of the volume of the satellite droplet, for example, the volume of the satellite droplet can be calculated by image processing, so that the volume calculation of the satellite droplet is more flexible and accurate.

[0044] In some embodiments, the mother droplet can be located on a preset first electrode in the plurality of first electrodes, the mother droplet is driven to move from the preset first electrode to the retaining electrode 1041 by applying a first driving voltage to part of the first electrodes in the first moving area, and the retaining electrode 1041 and the ejection electrode 1042 are simultaneously applied with a second driving voltage, so that the edge of the mother droplet covering the ejection neck vibrates locally and sprays a plurality of satellite droplets on the ejection electrode 1042 under the action of the second driving voltage, until the second driving voltage stops.

[0045] In addition, the second driving voltage is greater than the first driving voltage.

[0046] In the embodiments of the present application, when the first driving voltage is applied to a mother droplet on the surface of the hydrophobic dielectric layer 105, the surface tension of the solid-liquid-gas three-phase contact line changes, the contact angle of the mother droplet decreases and the wetting phenomenon occurs, so that the mother droplet can be driven to move; when the second driving voltage is applied, the contact line vibrates and a plurality of satellite droplets are ejected when the second driving voltage is greater than the ejection threshold voltage, which is called satellite droplet ejection.

[0047] In summary, the embodiments of the present application provide a microfluidic chip, which comprises: a top substrate and a bottom substrate, the top substrate and the bottom substrate are oppositely arranged to form a cavity, a conductive layer is arranged on the bottom surface of the top substrate, an electrode layer formed by a plurality of electrodes arranged in sequence is arranged on the top surface of the bottom substrate, and a dielectric layer surrounding the plurality of electrodes is further arranged on the electrode layer; wherein the plurality of electrodes comprise: a plurality of first electrodes in a first moving area, and a plurality of second electrodes in an ejection area in communication with the first moving area; the plurality of first electrodes are used to drive the mother droplet to move to the ejection area, and the plurality of second electrodes are used to control the mother droplet to eject in the ejection area; the plurality of second electrodes comprise: a retaining electrode and an ejection electrode, the retaining electrode is an electrode close to the first moving area, and the ejection electrode is an electrode away from the first moving area, and an ejection neck is arranged on one side of the ejection electrode facing the retaining electrode; the retaining electrode is used to retain the mother droplet, and the ejection electrode is used to make the mother droplet eject through the ejection neck and accommodate the formed satellite droplets. The top substrate and the bottom substrate are oppositely arranged to form a cavity, a conductive layer is arranged on the bottom surface of the top substrate, and an electrode layer is arranged on the top surface of the bottom substrate, and by applying a driving voltage to the electrodes, the liquid droplet can be driven to move and eject, thereby improving the convenience of microfluidic distribution. The electrode layer is formed by a plurality of electrodes arranged in sequence, and the microfluidic chip also has the characteristics of simple structure. Moreover, the ejection neck is arranged on one side of the ejection electrode facing the retaining electrode, and the ejection neck and the retaining electrode do not overlap, so that the satellite droplets are individually accommodated on the ejection electrode after ejection, which is conducive to the calculation of the volume of the satellite droplets.

[0048] It should be noted that the number of the plurality of first electrodes in the first moving area and the number of the plurality of second electrodes in the spraying area are not limited in the embodiments of the present application, and can be set according to actual needs.

[0049] Optionally, the retaining electrode 1041 is a regular polygon, and the number of sides of the regular polygon is greater than or equal to a preset threshold.

[0050] In some embodiments, the preset threshold can be 6, and the retaining electrode 1041 is an octagonal electrode or a hexagonal electrode. Of course, this is only an example, and the number of sides of the regular polygon can be set according to actual needs, as long as the number of sides of the regular polygon is greater than or equal to the preset threshold, and the embodiments of the present application do not make specific limitations.

[0051] As shown in FIG. 1, the retaining electrode 1041 can be an octagonal electrode. Figure 2

[0052] It should be noted that the octagonal shape, the hexagonal shape and the circular droplet edge are more consistent, and the droplet spraying at the four corners of the rectangle is avoided to avoid pollution of the electrode path.

[0053] Optionally, the plurality of first electrodes are a plurality of electrodes of a preset geometric shape.

[0054] It should be noted that the preset geometric shape can be a rectangular shape, a square shape, a shape with jagged edges, or a shape with protruding edges, and the embodiments of the present application do not make specific limitations. In the embodiments of the present application, the first electrode is connected to low-voltage electricity, and the second electrode is connected to high-voltage electricity.

[0055] Optionally, the plurality of first electrodes are a plurality of square electrodes, and the size of the plurality of square electrodes can be the same, and the gap between adjacent two square electrodes can also be the same.

[0056] Optionally, the arrangement gap of the plurality of first electrodes is smaller than the arrangement gap of the plurality of second electrodes.

[0057] Optionally, the arrangement gap of the plurality of first electrodes is smaller than the arrangement gap of the plurality of second electrodes, which can effectively avoid the dielectric layer 105 breakdown phenomenon that may exist when high-voltage driving.

[0058] Optionally, the arrangement gap of the plurality of first electrodes is any value in 10um to 30um, and the arrangement gap of the plurality of second electrodes is any value in 40um to 100um.

[0059] For example, the arrangement gap of the plurality of first electrodes is 10um, and the arrangement gap of the plurality of second electrodes can be 50um.

[0060] ​In some embodiments, the dimensions of the jet electrode 1042, excluding the jet neck portion, can be 1 mm x 1 mm, with a height of 100 μm and a width of 125 μm. Furthermore, the gap between the retaining electrode 1041 and the jet electrode 1042 can be 50 μm, effectively preventing dielectric layer 105 breakdown that may occur during high-voltage driving.

[0061] Optionally, the size of each square electrode can be 1mm*1mm, and the gap between two adjacent square electrodes can be 10μm.

[0062] Optionally, the electrode layer may also be provided with at least two fourth electrodes 106 that are on the same plane as the plurality of electrodes 104 and are disposed around the stationary electrode and the jetting electrode.

[0063] The fourth electrode 106 is disposed around the stationary electrode and the jetting electrode, and does not obstruct the movement, jetting and pickup of the mother liquor droplets.

[0064] Figure 3 This is a schematic diagram of the structure of an electrode in a microfluidic chip provided by an embodiment of the present invention, as shown below. Figure 3 As shown, the dielectric layer 105 is also provided with two adjacent fourth electrodes 106 that belong to the same plane as the multiple electrodes 104 and are symmetrically arranged on both sides of the jet neck.

[0065] like Figure 3 As shown, two adjacent fourth electrodes are disposed on both sides of the jet neck and are located on one side of the plurality of electrodes 104 (the lower side in the figure), and are on the same plane as the plurality of electrodes 104; of course, two adjacent fourth electrodes disposed on both sides of the jet neck can also be located on the other side of the plurality of electrodes 104 (the upper side in the figure), and are on the same plane as the plurality of electrodes 104. This application embodiment does not impose specific limitations on this.

[0066] Optionally, SU8 square columns are also provided on both sides of the jet neck to prevent mother liquor droplets from being driven onto the jet electrodes during the jetting process.

[0067] It should be noted that, since there are SU8 square columns on both sides of the jet neck, it is impossible to control the mother liquid droplets to move directly through the jet neck to the jet electrode for the re-entry operation. Therefore, it is possible to control the mother liquid droplets to pass through at least two fourth electrodes 106 to re-enter the satellite droplets on the jet electrode.

[0068] Optionally, the plurality of electrodes 104 further includes: a plurality of third electrodes in the second moving region, the plurality of third electrodes being arranged sequentially near the jetting electrode; the third electrodes are used to control the target droplet to pick up the satellite droplet in the second moving region.

[0069] It should be noted that the plurality of third electrodes are arranged close to the ejection electrode, and the plurality of third electrodes can be arranged on the upper side, the lower side or the left side (i.e. the side away from the ejection neck), and the embodiments of the present application do not make specific limitations thereon.

[0070] The second moving area can be a pickup path, and the number of the plurality of third electrodes in the second moving area can be set according to actual requirements, and the embodiments of the present application do not make specific limitations thereon.

[0071] Optionally, Figure 4 A structure diagram of an electrode in a microfluidic chip provided by the embodiments of the present application is shown in FIG. 4. Figure 4 As shown in FIG. 4, the plurality of third electrodes can be arranged in sequence close to the ejection electrode 1042 and on the side away from the ejection neck; the third electrode is used to control the target droplet to pick up the satellite droplet in the second moving area.

[0072] In some embodiments, a third driving voltage is sequentially applied to part of the plurality of third electrodes in the second moving area, to drive the target droplet to move in the second moving area and pick up the satellite droplet on the ejection electrode 1042.

[0073] In the embodiments of the present application, the target droplet can be located on a preset third electrode in the plurality of third electrodes, and the preset third electrode can be any electrode in the plurality of third electrodes, and the embodiments of the present application do not make specific limitations thereon.

[0074] It should be noted that after the target droplet picks up the satellite droplet on the ejection electrode 1042, the target droplet can be controlled to move to the original preset third electrode, or the target droplet can be controlled to move to other third electrodes in the plurality of third electrodes, so as to subsequently re-eject the satellite droplet.

[0075] Optionally, the plurality of electrodes 104 further include: a fifth electrode of a droplet containing area, the droplet containing area being in communication with the first moving area, to separate the droplet sample in the droplet containing area to generate a mother droplet, or to use the droplet sample to eat back the mother droplet.

[0076] Optionally, Figures 5a to 5d A principle diagram of generation of a mother droplet provided by the embodiments of the present application is shown in FIG. 5. Figure 5a As shown in FIG. 5, the fifth electrode of the droplet containing area has a droplet sample, a fourth driving voltage is applied to the fifth electrode, the retaining electrode 1041 and the first electrode in the first moving area, so that the droplet sample is elongated to cover the retaining electrode 1041 and the first electrode in the first moving area; and as shown in FIG. 6, the fourth driving voltage applied to the first electrode adjacent to the retaining electrode 1041 is stopped. Figure 5b Figure 5c ​As shown, a mother droplet is generated at the retaining electrode 1041, and the remaining droplet sample moves to the droplet accommodating area, i.e. moves back; the fourth driving voltage applied to the retaining electrode 1041 and the first electrode in the first moving area is stopped, while the fourth driving voltage applied to the fifth electrode is still maintained, as shown in FIG. 6C. Figure 5d As shown, the droplet sample is returned to the fifth electrode. In this way, a mother droplet with a size matching that of the retaining electrode 1041 is formed.

[0077] In addition, after the ejection of the satellite droplet by the plurality of second electrodes is completed, the satellite droplet can be collected by the mother droplet to remove the satellite droplet on the ejection electrode 1042, so as to re-eject.

[0078] In summary, the microfluidic chip provided by the embodiment of the present application includes a top substrate 101 and a bottom substrate 102 oppositely arranged to form a chamber, a conductive layer 103 arranged on the bottom surface of the top substrate 101, and an electrode layer arranged on the top surface of the bottom substrate 102. The application of a driving voltage to the electrodes can drive the droplet to move and eject, thereby improving the convenience of microfluidic distribution. The conductive layer 103 is formed by a plurality of electrodes 104 arranged in sequence, and the microfluidic chip also has the characteristic of simple structure. Moreover, the side of the ejection electrode 1042 facing the retaining electrode 1041 is provided with an ejection neck, and the ejection neck does not overlap the retaining electrode 1041. After ejection, the satellite droplet is accommodated on the ejection electrode 1042, which is beneficial to the calculation of the volume of the satellite droplet.

[0079] Optionally, Figure 6 A structural schematic diagram of a microfluidic system provided by the embodiment of the present application is shown in FIG. 7. Figure 6 As shown, the microfluidic system can include a controller 201, a signal generator 202, a relay array 203, and the microfluidic chip 100 in any of the above embodiments.

[0080] The input end of the relay array 203 is connected to the output end of the signal generator 202, the plurality of output ends of the relay array 203 are respectively connected to the plurality of electrodes 104 in the microfluidic chip 100, and the controller 201 is connected to the control end of the relay array 203.

[0081] In some embodiments, the signal generator 202 can continuously generate and output a driving signal to the relay array 203, and the controller 201 can output a control instruction to the relay array 203 to control the on-off of the relay array 203 to output the driving signal to a specific electrode.

[0082] It should be noted that the driving signal can include: a relatively low voltage TV (transportation voltage) signal for moving the droplet, which is a sine signal with a peak voltage of 150V and a frequency of 2kHz; and a relatively high voltage EV (ejection voltage) signal for droplet ejection, which is a spike pulse signal with a peak value of 440V and a frequency of 800Hz. The two signals are respectively sine and square wave small signals generated by a signal generator, amplified and deformed by a transformer.

[0083] In the embodiments of the present application, the first driving voltage, the third driving voltage and the fourth driving voltage are all generated based on the TV signal; and the second driving voltage is generated based on the EV signal.

[0084] To sum up, the embodiments of the present application provide a microfluidic system, the controller 201 can output control instructions to the relay array 203, control the on-off of the relay array 203, output the driving signal to the specific electrode, and apply the driving voltage to the specific electrode to drive the droplet to move and eject, thereby improving the convenience of microfluidic distribution. The conductive layer 103 is formed by a plurality of electrodes 104 arranged in sequence, and the microfluidic system also has the characteristics of simple structure.

[0085] The above only describes the preferred embodiments of the present application and is not used to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A microfluidic chip, characterized by, The microfluidic chip comprises: a top substrate and a bottom substrate oppositely arranged to form a cavity, a conductive layer arranged on the bottom surface of the top substrate, and an electrode layer formed by a plurality of electrodes arranged in sequence on the top surface of the bottom substrate, and a dielectric layer arranged on the electrode layer and surrounding the plurality of electrodes; wherein the plurality of electrodes comprises a plurality of first electrodes in a first moving area and a plurality of second electrodes in a jetting area communicating with the first moving area, the plurality of first electrodes are used to drive the mother droplet to move to the jetting area, and the plurality of second electrodes are used to control the mother droplet to jet in the jetting area; the plurality of second electrodes comprises a retaining electrode and a jetting electrode, the retaining electrode is an electrode close to the first moving area, and the jetting electrode is an electrode away from the first moving area, and a jetting neck is arranged on one side of the jetting electrode facing the retaining electrode; the retaining electrode is used to retain the mother droplet, and the jetting electrode is used to make the mother droplet jet through the jetting neck and accommodate the formed satellite droplet.

2. The microfluidic chip of claim 1, wherein, The retaining electrode is a regular polygon, and the number of sides of the regular polygon is greater than or equal to a preset threshold.

3. The microfluidic chip of claim 1, wherein, The plurality of first electrodes are a plurality of electrodes of a plurality of preset geometric shapes.

4. The microfluidic chip of claim 1, wherein, The arrangement gap of the plurality of first electrodes is smaller than the arrangement gap of the plurality of second electrodes.

5. The microfluidic chip of claim 4, wherein, The arrangement gap of the plurality of first electrodes is any value in 10 um to 30 um, and the arrangement gap of the plurality of second electrodes is any value in 40 um to 100 um.

6. The microfluidic chip of claim 1, wherein, The plurality of electrodes further comprises a plurality of third electrodes in a second moving area, the plurality of third electrodes are arranged in sequence at positions close to the jetting electrode; and the third electrodes are used to control the target droplet to pick up the satellite droplet in the second moving area.

7. The microfluidic chip of claim 1, wherein, The electrode layer further comprises at least two fourth electrodes arranged around the retaining electrode and the jetting electrode and belonging to the same plane as the plurality of electrodes.

8. The microfluidic chip of claim 1, wherein, The plurality of electrodes further comprises a fifth electrode in a droplet accommodating area, the droplet accommodating area communicates with the first moving area to separate a droplet sample in the droplet accommodating area to generate the mother droplet, or the droplet sample is used to eat back the mother droplet.

9. A microfluidic system, characterized in that The microfluidic chip comprises: a controller, a signal generator, a relay array, and the microfluidic chip of any one of claims 1-8, an input end of the relay array is connected to an output end of the signal generator, a plurality of output ends of the relay array are respectively connected to the plurality of electrodes in the microfluidic chip, and the controller is connected to a control end of the relay array.

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