Universal micro-nano flow pipeline normal pressure dead volume free interface

Abstract

The general-purpose micro-nano flow pipeline normal pressure dead volume-free interface relates to the fields of microfluidics and nanoflow liquid chromatography. It is composed of a hard sleeve, a soft sleeve and a pair of fixing screws. Through assembly and fixing, two capillaries are connected without dead volume to form a normal pressure dead volume-free pipeline connection port. The fixing screw is a through structure, which allows the capillary to pass through and can also fix the capillary without displacement. By using a double-layer sleeve and two special structure components, the two capillaries are stably connected without dead volume through mechanical fixation, and the interface is light and easy to operate. It can effectively avoid the phenomenon of dead volume in traditional capillary interfaces and increase the stability and reliability of nanoflow systems; only simple assembly is required to achieve a dead volume-free fixed connection of two capillaries, which is simple to operate, small in size, light in weight, economical and practical, and widely used; and the use of inert materials can enhance physical and chemical stability at the same time, making the interface more reliable.

Description

Technical Field

[0001] The invention relates to the field of microfluidics and nanoflow liquid chromatography, and in particular to a universal micro-nanoflow pipeline normal pressure dead volume free interface which is simple to operate and has a high success rate for connecting two capillaries without dead volume through a combination of a sleeve and a fixing screw. Background Art

[0002] The connection of micro-inner diameter pipeline channels is an important component in microfluidic and nanofluidic liquid chromatography systems. In particular, micro-nanofluidic pipeline connections without dead volume can improve the stability and reliability of the system. Traditional micro-nanofluidic pipeline interfaces are complex and cumbersome to operate, and their volume is large relative to the pipeline, and most of them cannot completely eliminate the existence of dead volume. Therefore, a new interface technology with small size, light weight, and more convenient use is urgently needed to be invented. Summary of the invention

[0003] The purpose of the present invention is to provide a universal micro-nano flow pipeline normal pressure dead volume free interface, which connects two capillaries without dead volume through a combination of a sleeve and a fixing screw, has simple operation and a high success rate, and can be widely used in the fields of microfluidics and nanoflow liquid chromatography.

[0004] The universal micro-nano flow pipeline normal pressure dead volume free interface is composed of a hard sleeve, a soft sleeve and a pair of fixing screws. Through assembly and fixing, two capillaries are connected without dead volume to form a normal pressure dead volume free pipeline connection port.

[0005] The two capillaries are butted against each other in the soft sleeve without dead volume, and the two capillaries and the soft sleeve are fixed in the hard sleeve by a pair of fixing screws on both sides.

[0006] The material of the capillary can be an inorganic, organic or inorganic-organic composite material, such as metal, glass, quartz, polyetheretherketone, polytetrafluoroethylene, etc.; the inner diameter of the two capillaries ranges from 2 to 5000 μm, the outer diameter of the capillary ranges from 10 to 10000 μm, and the two capillaries have the same or different inner diameters and outer diameters.

[0007] The soft sleeve seamlessly fixes the two capillaries. The soft sleeve can be made of a polymer material or an organic-inorganic composite material, preferably polytetrafluoroethylene or polyetheretherketone, which has a certain mechanical strength and stable chemical properties.

[0008] The hard sleeve has strong mechanical strength to play a role in fixing and protecting. The inner walls at both ends of the hard sleeve have threads matching the fixing screws. The combination of the hard sleeve and the fixing screws is used to fix the soft sleeve and the two capillaries. The material of the hard sleeve and the fixing screws can be organic or inorganic, preferably metal, polyetheretherketone and polytetrafluoroethylene.

[0009] The fixing screw is a through structure, which allows the capillary to pass through and can also fix the capillary without displacement; the fixing screw can fix the capillary by physical means, such as mechanical friction, or by the bonding force of glue.

[0010] In order to overcome the shortcomings of the low-pressure interface of the traditional micro-nano flow pipeline, the present invention provides a universal micro-nano flow pipeline normal pressure dead volume free interface, using a double-layer sleeve and two special structure components, through a mechanical fixation method, two capillaries are stably connected without dead volume, and the interface is light and easy to operate. In the present invention, only two sleeves and two fixing screws need to be combined and fixed, avoiding the use of traditional connecting devices such as two-way, screws and tough rings. It is easy to operate, small in size, light in weight, more convenient to use, wider in application range, economical and reliable; and the use of inert materials can enhance physical stability and chemical stability at the same time, making the interface more reliable. In the present invention, the interface is wrapped in a polymer sleeve and a metal sleeve in turn, the outer hard sleeve can protect the interface from external interference, and the inner soft sleeve has stable chemical properties and can maintain the stability of the interface for a long time. This interface technology can be widely used in the fields of microfluidics and nanoflow liquid chromatography. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is a schematic diagram of the structural composition of an embodiment of the present invention.

[0012] Figure 2 It is a schematic cross-sectional structural diagram of an embodiment of the present invention.

[0013] Figure 3 Schematic diagram of the decomposition structure of an embodiment of the present invention.

[0014] Figure 4 This is a schematic diagram of the assembly of the interface components of an embodiment of the present invention.

[0015] The marks in the figure are: 1. hard sleeve; 2. first capillary; 3. second capillary; 4. soft sleeve; 5. first fixing screw; 6. second fixing screw. DETAILED DESCRIPTION

[0016] The following examples will further illustrate the present invention in conjunction with the accompanying drawings. It should be noted that the present invention is not limited to the following examples. Any technical features and implementation schemes in the following examples are one or more of a variety of optional technical features and a variety of optional implementation schemes. For the sake of simplicity of description, this document cannot exhaustively list all the alternative technical features and implementation schemes contained in the present invention, so those skilled in the art should know that any technical features and implementation schemes in this embodiment do not limit the scope of protection of the present invention, and the scope of protection includes any alternative technical features and implementation schemes taken by all those skilled in the art without creative work. Specifically, the implementation schemes obtained by replacing any technical feature in the present invention or combining any two or more technical features provided by the present invention should be within the scope of protection of the present invention. If the specific technology and conditions are not indicated in the examples, they are carried out according to the technology and conditions described in the literature in this field or according to the product instructions, and the reagents or instruments used are not indicated by the manufacturer, which are all conventional products that can be purchased commercially.

[0017] like Figures 1 to 4 The universal micro-nano flow pipeline normal pressure dead volume free interface described in the embodiment of the present invention is composed of a hard sleeve 1, a soft sleeve 4, a first fixing screw 5 and a second fixing screw 6. Through assembly and fixation, the first capillary 2 and the second capillary 3 are connected without dead volume to obtain a normal pressure dead volume free pipeline connection port.

[0018] Furthermore, among all the components of the interface, the first capillary 2 and the second capillary 3 are butted in the soft sleeve 4 without dead volume, and the first capillary 2 and the second capillary 3 and the soft sleeve 4 are fixed in the hard sleeve 1 by the first fixing screw 5 and the second fixing screw 6 .

[0019] Furthermore, the two first capillaries 2 and second capillaries 3 connected without dead volume can be made of inorganic, organic or inorganic-organic composite pipes, such as metal, glass, quartz, polyetheretherketone, polytetrafluoroethylene, etc.; the inner diameters of the two capillaries range from 2 to 5000 μm, and the outer diameters range from 10 to 10000 μm, and the two capillaries have the same or different inner and outer diameters.

[0020] Furthermore, the soft sleeve 4 can seamlessly fix the first capillary 2 and the second capillary 3 . The soft sleeve 4 can be made of a polymer material or an organic-inorganic composite material, preferably polytetrafluoroethylene or polyetheretherketone, which has a certain mechanical strength and stable chemical properties.

[0021] Furthermore, the hard sleeve has strong mechanical strength and can play a role in fixing and protecting. The inner walls at both ends have threads that can match the fixing screws. The combination of the hard sleeve and the fixing screws can fix the soft sleeve and the two capillaries; the material of the hard sleeve and the fixing screws can be organic or inorganic, preferably metal, polyetheretherketone and polytetrafluoroethylene.

[0022] Furthermore, the fixing screw has a through structure, which allows the capillary to pass through, and can also fix the capillary to prevent displacement; the fixing screw can fix the capillary by physical means, such as mechanical friction, or by the bonding force of glue.

[0023] Furthermore, this interface is small in size, simple to prepare, and has excellent pressure resistance. It can be widely used in the connection of micro-nanofluidic pipelines and has broad application potential in the fields of microfluidics and nanoflow liquid chromatography.

[0024] The assembling method of the present invention is provided below, comprising the following steps:

[0025] 1) Assembly of two capillary normal pressure dead volume free interface components

[0026] Two quartz capillaries with different inner diameters are cut. The parameters of the first capillary 2 are as follows: 365μm outer diameter, 100μm inner diameter, and 20cm in length; the parameters of the second capillary 3 are as follows: 365μm outer diameter, 25μm inner diameter, and 20cm in length. The soft sleeve 4 is made of polytetrafluoroethylene (PTFE) material. The soft sleeve 4 is cut with the following parameters: 365μm inner diameter, 1500μm outer diameter, and 2cm in length. The hard sleeve 1 is made of aluminum-iron material, and its parameters are as follows: 1800μm inner diameter, 3000μm outer diameter, and 4cm in length. Place the first capillary 2, the second capillary 3, the soft sleeve 4 and the hard sleeve 1 as shown in the figure. Figure 4 Assembly. The capillary interface needs to be ground flat to achieve dead volume-free docking.

[0027] 2) Install the fixing screws to complete the interface assembly

[0028] The first capillary 2, the second capillary 3, the soft sleeve 4 and the hard sleeve 1 are connected and fixed by using two first fixing screws 5 and second fixing screws 6 that match the internal threads on both sides of the hard sleeve 1. The first fixing screws 5 and the second fixing screws 6 can be tightly squeezed with the soft sleeve 4 and fixed with the hard sleeve 1 at the same time, and the two fixing screws are fixed with glue to the two capillaries. The connected capillary is connected to the outlet of the high-pressure pump, and the pressure resistance of the interface is tested at a normal flow rate. There is no leakage, deformation or other damage at the interface, which proves that this interface has excellent stability.

[0029] The present invention connects two capillaries without dead volume through a combination of a sleeve and a fixing screw, and the operation is simple and the success rate is high. The present invention has outstanding advantages such as small size, simple preparation, and excellent pressure resistance. It can be widely used in the connection of micro-nano flow pipelines and has wide application potential in the fields of microfluidics and nanoflow liquid chromatography. The above embodiments are only preferred embodiments of the present invention and cannot be considered to limit the scope of implementation of the present invention. All equal changes and improvements made according to the scope of application of the present invention should still fall within the scope of the patent coverage of the present invention.

Claims

1. Universal micro-nano flow pipeline normal pressure dead volume free interface, characterized by It consists of a hard sleeve, a soft sleeve and a pair of fixing screws. Through assembly and fixing, two capillaries are connected without dead volume to form a pipeline connection port with normal pressure and no dead volume. The two capillaries are butted against each other in the soft sleeve without dead volume, and the two capillaries and the soft sleeve are fixed in the hard sleeve by a pair of fixing screws on both sides; The soft sleeve seamlessly fixes two capillaries; the soft sleeve is made of polymer material or organic-inorganic composite material; The inner walls at both ends of the hard sleeve have threads matching the fixing screws, and the combination of the hard sleeve and the fixing screws is used to fix the soft sleeve and the two capillaries; The fixing screw is a through structure, which is used for the capillary to pass through and fixes the capillary without displacement; the fixing screw fixes the capillary by mechanical friction or glue bonding.

2. The universal micro-nano flow pipeline normal pressure dead volume free interface as claimed in claim 1, characterized in that The capillary tube is made of inorganic, organic or inorganic-organic composite material, including metal, glass, quartz, polyetheretherketone and polytetrafluoroethylene.

3. The universal micro-nano flow pipeline normal pressure dead volume free interface as claimed in claim 1, characterized in that The inner diameter of the capillary is in the range of 2 to 5000 μm, the outer diameter of the capillary is in the range of 10 to 10000 μm, and the two capillaries have the same or different inner diameters and outer diameters.

4. The universal micro-nano flow pipeline normal pressure dead volume free interface as claimed in claim 1, characterized in that The soft sleeve is made of polytetrafluoroethylene or polyetheretherketone.

5. The universal micro-nano flow pipeline normal pressure dead volume free interface as claimed in claim 1, characterized in that The hard sleeve and the fixing screw are made of organic or inorganic materials, including metal, polyetheretherketone or polytetrafluoroethylene.

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