DNA fragmentation method and apparatus based on bubble interface vibration

Abstract

This invention relates to a DNA fragmentation method and apparatus based on bubble interfacial vibration. The method includes: during the flow of a DNA sample along a flow channel, two bubbles from a bubble pair act symmetrically on both sides of the flow channel, creating a gradually contracting and expanding section within the channel to generate a stretching flow field; the DNA molecular chains in the DNA sample break due to the stretching effect of the stretching flow field as they pass through the contracting and expanding section. This invention can effectively fragment DNA molecules without contaminating them.

Description

Technical Field

[0001] This invention relates to the field of DNA fragmentation, and more specifically to a DNA fragmentation method and apparatus based on bubble interface vibration. Background Technology

[0002] Due to the limitations of current detection technologies, the detection of certain diseases and gene research require cutting long DNA molecules into small fragments of approximately 500 base pairs. The fragmented length cannot be too short, otherwise it will increase the number of splicing points, potentially leading to sequencing errors. Current DNA fragmentation technologies suffer from drawbacks such as sample cross-contamination, high reagent requirements (e.g., jet nebulization methods), and non-random breakpoints (e.g., enzymatic degradation methods). Therefore, developing an effective DNA fragmentation technology is essential for the detection of certain diseases and gene research. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to overcome the defects of the prior art and provide a DNA fragmentation method based on bubble interface vibration, which can effectively fragment DNA molecules without contaminating them.

[0004] To solve the above-mentioned technical problems, the technical solution of the present invention is: a DNA fragmentation method based on bubble interface vibration, comprising:

[0005] As the DNA sample flows along the flow channel, the two bubbles of the bubble pair act symmetrically on both sides of the flow channel, creating a gradually narrowing and expanding section within the flow channel to generate a stretching flow field.

[0006] The DNA molecular chains in the DNA sample break due to the stretching of the stretching flow field as they pass through the tapering and expanding sections.

[0007] Furthermore, in order to enhance the stretched flow field, the method also includes:

[0008] By using ultrasound to vibrate the bubble interface, opposing vortices are generated on both sides of the bubble to enhance the stretching flow field.

[0009] The present invention also provides a DNA fragmentation device based on bubble interface vibration, comprising a microfluidic system, the microfluidic system including a flow channel, a plurality of bypass pairs arranged along the extension direction of the flow channel, and a gas channel connecting all the bypass pairs, wherein each bypass pair has two bypasses symmetrically connected to both sides of the flow channel; wherein,

[0010] As the DNA sample flows along the flow channel, the air bubbles in the two bypasses of the bypass pair act symmetrically on both sides of the flow channel, creating a gradually narrowing and expanding section within the flow channel to generate a stretching flow field.

[0011] The stretching flow field is used to stretch the DNA molecular chains in the DNA sample as they pass through the tapering and expanding sections of the flow channel, causing the DNA molecular chains to break.

[0012] Furthermore, in order to control the degree of expansion of the stretching flow field, a regulating valve is provided on the main air passage of the air passage.

[0013] This further increases the shearing and stretching time of the DNA sample within the meandering flow channel.

[0014] Furthermore, the DNA fragmentation device based on bubble interface vibration also includes an ultrasonic generator, which includes a control box and multiple transducers. The multiple transducers are respectively connected to the control box and distributed on both sides outside the flow channel to generate ultrasonic waves.

[0015] Furthermore, to improve processing capacity, the microfluidic system may have several microfluidic systems connected in series and / or in parallel.

[0016] Furthermore, the flow channel and the bypass are fabricated on a main body plate using micromachining technology.

[0017] By adopting the above technical solution, DNA molecular chains are fragmented using the stretching flow field generated by the gradually expanding and contracting segments formed by bubble pairs. The reason for using bubble pairs to generate the stretching flow field is that the bubble interface is clean and will not cause secondary contamination. Furthermore, the degree of expansion of the stretching flow field can be controlled simply by controlling the shape of the bubble interface, without replacing or changing any components, thereby altering the stretching strength of the flow field. Moreover, when the DNA sample contains impurities, they will be adsorbed onto the bubble interface. After fragmentation, these adsorbed impurities are easily removed. Ultrasonic waves can also be used to vibrate the bubble interface, generating opposing vortices to enhance the stretching flow field and produce a stronger stretching effect. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the tensile flow field of the gradually contracting and expanding section formed by bubble pairs according to the present invention.

[0019] Figure 2 This is a schematic diagram of the vortices generated by the bubble interface vibration of the present invention;

[0020] Figure 3 This is a schematic diagram of the DNA fragmentation device based on bubble interface vibration of the present invention. Detailed Implementation

[0021] To make the content of this invention easier to understand, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0022] Example 1

[0023] like Figure 1 As shown, a DNA fragmentation method based on bubble interface vibration includes:

[0024] As the DNA sample flows along the flow channel 1, the two bubbles 2 of the bubble pair act symmetrically on both sides of the flow channel 1, so that the flow channel 1 has a gradually narrowing and expanding section to generate a tensile flow field.

[0025] The DNA molecular chains in the DNA sample break due to the stretching of the stretching flow field as they pass through the tapering and expanding sections.

[0026] In this embodiment, the bubble 2 is a nitrogen bubble.

[0027] Specifically, this embodiment is based on fluid mechanics principles, utilizing the stretching flow field generated by the gradually expanding and contracting sections formed by bubble pairs to achieve DNA molecular chain fragmentation. The reason for using bubble pairs to generate the stretching flow field is that the bubble 2 interface is clean and will not cause secondary contamination. Furthermore, without replacing or altering any components, the expansion degree of the stretching flow field can be controlled simply by controlling the shape of the bubble 2 interface, thereby changing the stretching strength of the flow field. Moreover, when the DNA sample contains impurities, they will be adsorbed onto the bubble 2 interface. After fragmentation is complete, the adsorbed impurities are easily removed.

[0028] Example 2

[0029] like Figure 2 As shown, this embodiment, based on embodiment one, further includes:

[0030] By using ultrasound to vibrate the interface of bubble 2, opposite vortices are generated on both sides of bubble 2 to enhance the stretching flow field.

[0031] Specifically, under the action of ultrasound, the internal pressure of bubble 2 changes, and the surface of bubble 2 vibrates due to the pressure fluctuations, thereby driving the surrounding fluid, i.e. the DNA sample, to generate opposite vortices on both sides of bubble 2, thereby strengthening the tensile flow field, promoting the breaking of DNA molecular chains, enhancing the ability of DNA molecular chains to fragment, and achieving efficient fragmentation of DNA molecular chains.

[0032] Example 3

[0033] like Figure 3 As shown, a DNA fragmentation device based on bubble interface vibration includes a microfluidic system. The microfluidic system includes a flow channel 1, multiple bypass pairs arranged along the extension direction of the flow channel 1, and a gas channel 4 connecting all the bypass pairs. Each bypass pair has two bypasses 3 symmetrically connected to both sides of the flow channel 1.

[0034] As the DNA sample flows along the flow channel 1, the air bubbles 2 in the two bypasses 3 of the bypass pair act symmetrically on both sides of the flow channel 1, so that the flow channel 1 has a gradually narrowing and expanding section to generate a stretching flow field.

[0035] The stretching flow field is used to stretch the DNA molecular chain in the DNA sample as it passes through the tapering and expanding sections of the flow channel 1, causing the DNA molecular chain to break.

[0036] In this embodiment, the flow channel 1 has a DNA sample inlet and a DNA sample outlet. The airway is divided into a main airway and multiple micro airways, which connect the main airway and the bypass 3.

[0037] like Figure 3 As shown, a regulating valve 5 is installed on the main air passage of the air passage 4.

[0038] Specifically, during operation, nitrogen gas is first introduced to purge the flow channel 1 clean, then the DNA sample is introduced, and the nitrogen inlet of the gas channel 4 is closed at the same time. When the DNA sample flows through the flow channel 1, the nitrogen gas in the flow channel 1 is discharged, and a gas-liquid interface is formed at the junction of the flow channel 1 and the bypass 3 on both sides. The curvature of the bubble interface 2 is adjusted by adjusting the regulating valve 5, that is, the degree of expansion of the bubble to the gradually contracting and expanding section is adjusted.

[0039] like Figure 3 As shown, the flow channel 1 is meandering. This design increases the length of the flow channel 1 per unit area and increases the pressure drop, thus increasing the shearing and stretching time of the DNA sample within the flow channel 1. In this embodiment, the flow channel 1 is sinusoidal. The bypass 3 is perpendicular to the flow channel 1.

[0040] In this embodiment, the flow channel 1 and the bypass 3 are machined onto the main body plate using micromachining technology. A top cover plate is then placed on the main body plate and sealed tightly. The micromachining technology is either microcasting or 3D printing.

[0041] Example 4

[0042] like Figure 3 As shown, this embodiment further includes an ultrasonic generator in addition to the third embodiment. The ultrasonic generator includes a control box 6 and multiple transducers 7. The multiple transducers 7 are respectively connected to the control box 6 and distributed on both sides outside the flow channel 1 to generate ultrasonic waves.

[0043] Turn on the ultrasonic generator and use the transducer 7 to generate ultrasonic waves to achieve micro-vibration of the gas-liquid interface. This generates opposing vortices on both sides of the bypass 3 within the flow channel 1, thereby enhancing the stretching effect of the stretching flow field.

[0044] Example 5

[0045] like Figure 3 As shown, this embodiment includes several microfluidic systems as described in Embodiment 3, and these microfluidic systems are connected in series and / or in parallel.

[0046] The microfluidic system in Example 3 can operate continuously. If the processing capacity of a single microfluidic system is too small, several microfluidic systems can be connected in parallel to work together to increase the processing capacity. If the DNA molecule chain is too long after processing by a single microfluidic system and does not meet the requirements of subsequent detection, several microfluidic systems can be connected in series to work together to reduce the length of the DNA molecule chain. If it is desired to both increase the processing capacity and reduce the length of the processed DNA molecule chain, several microfluidic systems can be connected in series and parallel.

[0047] Based on the above-described preferred embodiments of the present invention, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the inventive concept. The technical scope of this invention is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. A DNA fragmentation method based on bubble interface vibration, characterized in that, include: During the flow of the DNA sample along the flow channel (1), the two bubbles (2) of the bubble pair act symmetrically on both sides of the flow channel (1), so that the flow channel (1) has a gradually narrowing and expanding section to generate a stretching flow field. By using ultrasound to vibrate the interface of the bubble (2), opposite vortices are generated on both sides of the bubble (2) to enhance the stretching flow field; The DNA molecular chains in the DNA sample break due to the stretching of the stretching flow field as they pass through the tapering and expanding sections.

2. A DNA fragmentation device based on bubble interface vibration, characterized in that, The system includes a microfluidic system comprising a flow channel (1), multiple bypass pairs arranged along the extension direction of the flow channel (1), and an air passage (4) connecting all the bypass pairs. Each bypass pair has two bypasses (3) symmetrically connected to both sides of the flow channel (1). During the flow of the DNA sample along the flow channel (1), the air bubbles (2) in the two bypasses (3) of the bypass pair act symmetrically on both sides of the flow channel (1), so that the flow channel (1) has a gradually narrowing and expanding section to generate a stretching flow field. The stretching flow field is used to stretch the DNA molecular chain in the DNA sample as it passes through the gradually narrowing and expanding section along the flow channel (1) so that the DNA molecular chain breaks. It also includes an ultrasonic generator, which includes a control box (6) and multiple transducers (7). The multiple transducers (7) are respectively connected to the control box (6) and distributed on both sides outside the flow channel (1) to generate ultrasonic waves.

3. The DNA fragmentation device based on bubble interface vibration according to claim 2, characterized in that, A regulating valve (5) is provided on the main airway of the airway (4).

4. The DNA fragmentation device based on bubble interface vibration according to claim 2, characterized in that, The flow channel (1) is winding and tortuous.

5. The DNA fragmentation device based on bubble interface vibration according to claim 2, characterized in that, The microfluidic system may have several components, which may be connected in series and / or in parallel.

6. The DNA fragmentation device based on bubble interface vibration according to claim 2, characterized in that, The flow channel (1) and the bypass (3) are processed on a main body plate using micromachining technology.

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