Manual digital chip device and application thereof
By designing a manual digital chip device and using a threaded knob and piston with negative pressure drive, the problem of existing digital detection devices relying on complex equipment is solved, realizing low-cost, rapid, and sensitive nucleic acid detection, which is suitable for field applications.
Patent Information
- Application Number
- CN202511645093.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-11
- Publication Date
- 2026-01-23
AI Technical Summary
Existing digital testing devices rely on complex and expensive driving equipment, which makes it difficult to meet the needs of on-site, rapid, and low-cost nucleic acid testing.
A manual digital chip device was designed, which adopts a negative pressure drive method of threaded knob and piston to realize sample digitization through manual operation. It includes a sample injection area, an array area and a drive area. The structure is simple and suitable for disposable or split use, reducing the dependence on expensive equipment.
It enables low-cost and efficient nucleic acid testing, is easy for ordinary people to operate, is suitable for grassroots units and resource-scarce areas, has high sensitivity and accurate quantitative capabilities, lowers the equipment and usage threshold, and avoids liquid splashing and cross-contamination.
Smart Images
Figure CN121379799A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of biological detection, in particular to a portable and manually operated digital chip device for nucleic acid detection and application thereof. BACKGROUND
[0002] Nucleic acids (such as DNA and RNA) are the core molecules of life activities, and the changes in their specific sequences or expression levels are closely related to the occurrence and development of many diseases. Nucleic acid detection technology is widely used in clinical diagnosis, disease monitoring, drug research and development, pathogen detection, forensic identification and environmental monitoring fields, and has important application value. Rapid and high-sensitivity detection of nucleic acids is conducive to early detection and early treatment of abnormal target substances. In addition, quantitative detection of nucleic acids is particularly important for judging the disease stage, for example, circulating tumor DNA in peripheral blood can be used for cancer staging.
[0003] Currently, the techniques for quantitative detection of nucleic acids mainly include fluorescence quantitative analysis technology and digital analysis technology (i.e. digital PCR, dPCR). Among them, fluorescence quantitative analysis technology, especially fluorescence quantitative PCR (polymerase chain reaction), is widely used in clinical detection and research. However, this technology relies on expensive fluorescence quantitative PCR instruments. Other nucleic acid amplification techniques based on fluorescence quantification, such as LAMP (loop-mediated isothermal amplification), are also widely used in scientific research. However, the sensitivity of this technology needs to be improved, and it is difficult to identify low-abundance nucleic acid molecules, which is prone to false negatives.
[0004] Digital analysis technology has obvious technical advantages in low-abundance detection and accurate quantification, and is mainly divided into droplet digital technology and chip digital technology according to technical characteristics. Among them, the droplet digital technology uses water-in-oil microemulsion droplets, that is, 0.5-5 nL of nucleic acid amplification reaction solution is wrapped in immiscible oil phase one by one. Finally, the number of positive samples in the droplet is used to quantitatively calculate the target, realizing absolute quantification without relying on standard curve, with extremely high sensitivity and accuracy. The chip digital technology has the same principle as the droplet digital technology, and the difference lies in that the micro-reaction units are separated by the physical isolation of the chip structure. Its throughput is lower than that of the droplet type, but the stability of the micro-reaction units obtained by physical separation is obviously better than that of the droplet type. The latter is affected by the performance of water-in-oil, and is prone to droplet instability and fusion phenomenon.
[0005] Although digital technology has natural advantages in low-abundance and high-sensitivity nucleic acid detection, the current sample preparation (digitalization) process of these technologies still relies on complex equipment, which is difficult to meet the detection needs in the field or in the absence of equipment. Therefore, it is urgent to develop a portable and low-cost digital analysis platform. The technical problem to be solved by the present application is to overcome the defects of the existing digital detection device which relies on complex and expensive driving equipment and cannot meet the needs of on-site, rapid and low-cost detection. SUMMARY
[0006] To solve the technical problems of the existing digital detection technology which relies on complex and expensive driving equipment and is difficult to apply in the field and resource-limited environment, the present application provides a manual digital chip device which is ingenious in structure, low in cost and easy to operate. The device does not need external power supply or precise pump valve, and can complete efficient sample digitalization process through manual operation, and is particularly suitable for on-site rapid nucleic acid detection.
[0007] To achieve the above-mentioned purpose, the present application adopts the following technical solutions:
[0008] A manual digital chip device, comprising a sample inlet area, an array area and a driving area.
[0009] The sample inlet area is composed of a liquid inlet and a liquid storage cavity, and is used for introducing an aqueous reaction liquid containing a nucleic acid to be detected and an oil phase. The liquid inlet is sealed with a sealing plug, which effectively prevents pollution and facilitates reagent storage and transportation.
[0010] The array area is a digital micro-reaction unit storage area, which is provided with tens of thousands of micro-cavities and connecting pipelines. Crucially, the height of the micro-cavity is designed to be 3 times the height of the connecting pipeline. This structural difference provides a physical basis for subsequent accurate replacement of the aqueous phase in the pipeline by the oil phase and realization of stable digitalization.
[0011] The driving area is the core of the present application for realizing manual driving, and is composed of a cavity, a piston and a threaded knob. By manually rotating the threaded knob, the user can drive the piston connected thereto to smoothly move upward in the cavity, thereby generating a controllable negative pressure. This negative pressure serves as the only driving force to drive the liquid to flow from the sample inlet area to the array area according to a predetermined path, and completes the entire digitalization process.
[0012] The device can be designed as an integrated structure with high integration, which is convenient for one-time use. Alternatively, the sample inlet area and the driving area can be designed as independent modules which can be repeatedly used, and are connected to the array area chip which is a consumable through a standardized interface. This design improves the flexibility of use and reduces the long-term use cost.
[0013] Compared with the prior art, the present application has the following remarkable beneficial effects:
[0014] 1. Through the innovative manual drive design (threaded knob and piston), the dependence on expensive and cumbersome external drive devices (such as syringe pump, pressure controller) is completely abandoned. The device structure is simple, and low-cost materials such as plastic can be used for one-time injection molding, greatly reducing the manufacturing and use cost, making it possible for high-performance digital detection technology to be popularized in basic units, field sites and resource-poor areas.
[0015] 2. The entire digital process only needs three simple steps of "injecting sample - standing - rotating knob", without complex equipment debugging and professional fluid operation skills, ordinary people can complete it after simple guidance, greatly reducing the use threshold.
[0016] 3. The unique negative pressure drive mode provides smooth and continuous fluid power, avoiding liquid splashing or pressure surge that may be caused by pulse positive pressure.
[0017] The key structural design of the microcavity height 3 times the pipeline in the array area, combined with the specific gravity difference and interfacial tension of oil and water two phases, can ensure that the water phase in the pipeline is efficiently and thoroughly replaced under the driving of the oil phase, and the water phase in the microcavity is completely retained, thereby forming tens of thousands of discrete and uniform volume micro-reaction units, realizing a chamber filling rate of more than 95% and extremely low cross contamination risk, and stable and reliable digital effect.
[0018] 4. The split design concept allows the core drive and sample introduction module to be reused, and only the chip part containing the microcavity array is replaced, which is economical and environmentally friendly, and also facilitates the adaptation of chips with different flux or different detection projects. The aspect ratio of the microcavity can be 1.5 to 2.3 to achieve efficient digitalization, providing flexible space for optimizing chip design for different applications.
[0019] 5. Based on the digital principle of physical isolation, the present application can realize absolute quantification without standard curve, especially suitable for high-sensitivity and accurate quantification detection of low-abundance nucleic acid targets, effectively avoiding the problems of insufficient sensitivity and inaccurate quantification in low-concentration sample detection in traditional fluorescent quantitative PCR technology.
[0020] The present application also protects the application of the manual digital chip device in the field of nucleic acid detection, including but not limited to disease diagnosis, pathogen rapid detection, tumor liquid biopsy, gene expression analysis, etc. BRIEF DESCRIPTION OF DRAWINGS
[0021] Figure 1 is a perspective view of the device of the present application.
[0022] Figure 2 is a structural design side sectional view of the integrated chip device of the present application.
[0023] Figure 3 is a schematic diagram of the device of the present application in use, in which: A indicates the state of the chip before use, the chip is filled with oil phase; B indicates that the aqueous phase reaction solution is injected into the sample inlet area of the chip; C indicates that after waiting for 1 minute, the aqueous phase reaction solution falls to the bottom of the liquid storage cavity; D indicates that the threaded knob is manually rotated to drive the connected piston to move upward, forming a negative pressure driving force in the negative pressure cavity; E indicates that the aqueous phase reaction solution enters the array area under the driving of the negative pressure; F indicates that the subsequent oil phase continues to flow into the array area, thereby completing the digitization process.
[0024] Figure 4 is a schematic diagram of the digitization process of the array area microcavity of the present application, in which: A is that the array area is filled with oil phase before the aqueous phase reaction solution enters; B is that the aqueous phase reaction solution enters the microcavity under the driving of the negative pressure; C is that the aqueous phase reaction solution completely fills the array area; D is that the subsequent oil is used to flush away the aqueous phase reaction solution in the pipeline, and the digitized structure is obtained.
[0025] Figure 5 is a split device diagram of the present application.
[0026] Figure 6 is a schematic diagram of the digitization sample process and microcavity structure of the present application, which shows four kinds of microcavity structures with consistent width and height, and length of 1.5 times to 2.3 times of the width. DETAILED DESCRIPTION
[0027] The present application will be described in detail below in combination with all the drawings and examples, so that those skilled in the art can understand and implement the present application.
[0028] Overall device overview
[0029] Figure 1 shows the overall three-dimensional perspective view of the manual digitization chip device of the present application. As shown in the figure, the device structure is compact, convenient to hold and operate. The main operating components visible on the outside are the threaded knob of the driving area and the liquid inlet of the sample inlet area, and the overall design embodies the characteristics of portability and user friendliness.
[0030] Example one: integrated chip device
[0031] Figure 2 shows the side cross-sectional structural design diagram of the integrated chip device of the present application. The device adopts a highly integrated design, and all functional units are compactly integrated in a single chip. The chip main body can be integrally formed by precise injection molding using transparent high molecular materials such as polymethyl methacrylate (PMMA) or cyclic olefin polymer (COP), so as to facilitate the observation of liquid flow and subsequent fluorescence detection. The device is clearly divided into three functional areas in structure: sample inlet area, array area and driving area.
[0032] Sample inlet: Located at one end of the device, it is the sample entry and processing area. Its structure includes:
[0033] Liquid inlet: Used to inject the aqueous phase reaction solution (e.g. DNA sample treated with amplification reagents) and oil phase (e.g. fluorinated oil containing surfactant) through a micropipette or syringe.
[0034] Sealing plug: Used to seal the liquid inlet, made of puncturable rubber or silicone, which can effectively prevent contaminants from entering and keep the system sealed.
[0035] Liquid storage chamber: Connected to the liquid inlet, used to temporarily store the injected liquid.
[0036] Array area: As the core functional area, it is connected to the sample inlet area through microchannels and is the area for digital reaction. Its internal structure consists of a microfluidic network composed of thousands to millions of microchambers and connecting pipelines.
[0037] Drive area: Located at the other end of the device, it is the manually operated area that generates fluid power. Its core components include:
[0038] Negative pressure chamber: A closed cavity.
[0039] Piston: Placed in the negative pressure chamber, its outer periphery can be provided with an O-ring to ensure airtightness.
[0040] Threaded knob: Connected to the piston through a threaded transmission pair.
[0041] Device usage process details
[0042] Figure 3 The sequence diagram shows the complete operation process of the device from preparation to completion of digitalization:
[0043] Figure 3 A indicates the state of the chip before use, at this time the chip is completely filled with oil phase, and the specific gravity of the oil phase is less than that of the aqueous phase reaction solution.
[0044] Figure 3 B indicates that the aqueous phase reaction solution is injected into the chip through the liquid inlet of the sample inlet area, and then the injection device is removed.
[0045] Figure 3 C indicates that after standing for about 1 minute, due to the difference in specific gravity, the aqueous phase reaction solution settles and gathers at the bottom of the liquid storage chamber.
[0046] Figure 3 D indicates that the user starts to manually rotate the threaded knob of the drive area. This operation will pull the connected piston upwards to form the required negative pressure driving force in the negative pressure chamber.
[0047] Figure 3Middle E indicates that under the driving of negative pressure, the water phase reaction solution flows along the arrow direction, enters and fills the entire network of the array area.
[0048] Figure 3 Middle F indicates that the subsequent oil phase continues to flow into the array area under the continuous action of negative pressure, flushes away the water phase reaction solution in the pipeline, and ensures that the water phase reaction solution in the microcavity is stably retained, thereby completing the entire digitization process. After the digitization is completed, the chip is left for subsequent nucleic acid amplification and detection analysis.
[0049] Microscopic process of array area digitization
[0050] Figure 4 The digitization mechanism of the array area at the microscopic level is further described, and the key structure is that the height of the microcavity is 3 times the height of the connecting pipeline.
[0051] Figure 4 Middle A is the initial state, showing that before the reaction phase enters, the microcavities and pipelines of the array area are filled with oil phase.
[0052] Figure 4 Middle B shows that under the driving of negative pressure, the water phase reaction solution begins to enter the microcavity and expel the oil phase therein.
[0053] Figure 4 Middle C shows that the water phase reaction solution has completely filled all the microcavities and pipelines of the array area.
[0054] Figure 4 Middle D shows that the subsequent oil phase enters, and uses its flow shear force and the flow resistance difference caused by the height difference between the microcavity and the pipeline to accurately "flush away" the water phase reaction solution in the pipeline, while the water phase in the microcavity is completely retained due to the different forces, and finally forms a plurality of independent micro-reaction units physically isolated by the oil phase, that is, the digitization is completed.
[0055] Example 2: Split device
[0056] Figure 5 The split device embodiment of the application is shown. The design clearly divides the device into three independent parts: a sample injection module, a driving module, and an array reaction area (i.e. the chip body), which are connected through a precise mechanical interface.
[0057] Sample injection module: The core of this module is a liquid storage cavity, which is provided with a liquid inlet above and sealed by a sealing plug. The liquid storage cavity is connected to the array reaction area through an interface.
[0058] Driving module: This module is the power source for generating negative pressure, and the core components include a threaded knob, a piston, and a negative pressure cavity. The module is connected to the array reaction area through another interface.
[0059] Array reaction zone: This is the functional core region, i.e. the chip itself containing the array of microchambers.
[0060] The operation procedure of the split device is consistent with that of the integrated device Figure 3 but its advantage lies in that the core driving and injection module is reusable, and only the array reaction zone chip is disposable consumables, which significantly reduces the long-term use cost and increases the flexibility of use.
[0061] Digitization process verification and microchamber structure
[0062] Figure 6 Again, the complete digital injection process in the chip is emphasized in the form of a schematic diagram, and four different microchamber structures are shown. As Figure 6 shown, under the action of negative pressure driving, the reaction phase liquid enters the microchamber and expels the oil phase, and then the oil phase expels the reaction phase in the pipeline, leaving only the reaction phase in the microchamber. The four microchamber structures shown have consistent width and height, and the length is 1.5 times, 1.8 times, 2.0 times and 2.3 times the width, respectively. Experimental results prove that microchamber structures within this ratio range can achieve high-efficiency digital filling, indicating that the invention has a certain fault tolerance and adaptability to the specific shape of the microchamber, enhancing the robustness of the design.
Claims
1. A manually digitizing chip device, characterized by, The application relates to a manual digital chip device. The device comprises: a sample injection area for introducing aqueous phase reaction solution and oil phase; an array area provided with a plurality of microchambers and connecting channels for realizing digital distribution of samples; 2. The apparatus of claim 1, wherein, a driving area for generating negative pressure by manual operation to drive liquid from the sample injection area to the array area to complete the digital process.
3. The apparatus of claim 1, wherein, The sample injection area comprises a liquid inlet and a liquid storage cavity, and the liquid inlet is sealed by a sealing plug.
4. The apparatus of claim 1, wherein, The driving area comprises a cavity, a piston and a threaded knob, and the piston is driven to move in the cavity by manually rotating the threaded knob to generate negative pressure.
5. The apparatus of claim 1, wherein, The height of the microchamber in the array area is 3 times the height of the connecting channel.
6. The apparatus of claim 1, wherein, The device is of an integrated structure.
7. The apparatus of claim 1, wherein, The device is of a split structure, wherein the sample injection area and the driving area are independent modules connected with the array area through an interface. The length of the microchamber in the array area is 1.5 to 2.3 times the width of the microchamber.
9. A method of digitizing a sample using the apparatus of any one of claims 1 to 7, characterized in that, 8. Application of the manual digital chip device in nucleic acid detection. The application comprises the following steps: filling the device with oil phase; injecting aqueous phase reaction solution into the sample injection area; standing the device to make the aqueous phase reaction solution settle at the bottom of the liquid storage cavity; manually operating the driving area to generate negative pressure and drive the aqueous phase reaction solution into and fill the microchambers of the array area; continuing to drive the oil phase to flow into the array area to replace the aqueous phase reaction solution in the connecting channels, so that the aqueous phase reaction solution is isolated in the microchambers to complete the digital process.