阅读说明：本技术 微色谱柱及制备方法 (Micro chromatographic column and preparation method thereof ) 是由 冯飞 陈泊鑫 于 2021-01-22 设计创作，主要内容包括：本发明提供一种微色谱柱及制备方法,微色谱柱包括衬底、微沟道及椭圆微柱阵列,可使得微柱后的“准零流速区”的区域大大缩小；可在增加椭圆微柱数量的同时调整椭圆微柱的短轴长度q,以在保持微沟道的宽度w及微沟道的有效宽度d不变的前提下,可有效提高柱内表面积,同时可有效解决因微柱数量的增加而带来的柱前压力升高的问题；通过在沿微沟道的宽度方向上,将n列椭圆微柱之间、椭圆微柱与微沟道的侧壁之间设计成具有不同的间距,可进一步的缓解载气流速不均的问题,以进一步的使得柱内的流速分布均匀；本发明的微色谱柱结构和制备工艺简单,可提高微色谱柱的功效、减小供气系统的负担,有利于便携式应用,使得微色谱柱具有广泛的应用前景。(The invention provides a micro chromatographic column and a preparation method thereof, wherein the micro chromatographic column comprises a substrate, a micro channel and an elliptical micro column array, so that the area of a quasi-zero flow velocity area behind the micro column can be greatly reduced; the length q of the short axis of the elliptic microcolumn can be adjusted while the number of the elliptic microcolumns is increased, so that the inner surface area of the column can be effectively improved on the premise of keeping the width w of the microchannel and the effective width d of the microchannel unchanged, and the problem of pressure rise in front of the column caused by the increase of the number of the microcolumns can be effectively solved; by designing different intervals between the n rows of elliptical micro-pillars and between the elliptical micro-pillars and the side walls of the micro-channels in the width direction of the micro-channels, the problem of non-uniform flow velocity of the carrier gas can be further alleviated, so that the flow velocity distribution in the pillars is further uniform; the micro-chromatographic column has simple structure and preparation process, can improve the efficacy of the micro-chromatographic column, reduce the burden of an air supply system, is beneficial to portable application, and has wide application prospect.)

1. A micro chromatography column, characterized in that it comprises:

a substrate;

a microchannel, the microchannel being located in the substrate, the microchannel having a width w and an effective width d;

the elliptic micro-columns are positioned in the micro-channels, n columns of the elliptic micro-columns are arranged at intervals in the width direction of the micro-channels, m rows of the elliptic micro-columns are arranged at intervals in the extending direction of the micro-channels to form an n x m elliptic micro-column array, the long axis direction of the elliptic micro-columns is parallel to the extending direction of the micro-channels, the short axis direction of the elliptic micro-columns is parallel to the width direction of the micro-channels, and the length q of the short axis of the elliptic micro-columns is (w-d)/n.

2. The micro chromatography column of claim 1, wherein: and in the width direction of the micro channel, the n adjacent columns of the elliptic micro columns are arranged at equal intervals.

3. The micro chromatography column of claim 1, wherein: the n columns of the elliptical micro-pillars have different pitches in the width direction of the micro-channel, and the pitches gradually decrease in the extending direction from the center of the micro-channel to the side wall of the micro-channel.

4. The micro chromatography column of claim 1, wherein: in the width direction of the micro channel, the spacing between the adjacent n columns of the elliptical micro pillars is smaller than the spacing between the elliptical micro pillars at the edge and the side wall of the micro channel.

5. The micro chromatography column of claim 1, wherein: the width w of the micro-channel is 100-600 mu m, the effective width d of the micro-channel is 50-300 mu m, the length p of the long axis of the elliptic micro-column is 10-150 mu m, the length q of the short axis of the elliptic micro-column is 5-75 mu m, and the ratio of the length p of the long axis of the elliptic micro-column to the length q of the short axis of the elliptic micro-column is 3: 2-30: 1.

6. The micro chromatography column of claim 1, wherein: the width w of the micro-channel is 250 micrometers, the effective width d of the micro-channel is 130 micrometers, the length p of the long axis of the elliptic micro-column is 60 micrometers, and the length q of the short axis of the elliptic micro-column is 10 micrometers-40 micrometers.

7. The micro chromatography column of claim 1, wherein: the microchannel extends in a serpentine shape; the substrate comprises a silicon substrate, a glass substrate or a ceramic substrate; the micro chromatographic column further comprises a cover plate, the cover plate is bonded on the substrate and covers the micro channel, and the cover plate comprises a glass cover plate, a silicon cover plate or a ceramic cover plate.

8. A method for preparing a micro-chromatographic column is characterized by comprising the following steps:

providing a substrate;

forming a patterned mask layer on the surface of the substrate;

etching the substrate based on the patterned mask layer to form a micro-channel and an elliptical micro-column in the substrate, wherein the micro-channel is located in the substrate, the width of the micro-channel is w, and the effective width of the micro-channel is d; the elliptic microcolumns are positioned in the microchannels, n columns of the elliptic microcolumns are arranged at intervals in the width direction of the microchannels, m rows of the elliptic microcolumns are arranged at intervals in the extending direction of the microchannels to form an n x m elliptic microcolumn array, the long axis direction of the elliptic microcolumns is parallel to the extending direction of the microchannels, the short axis direction of the elliptic microcolumns is parallel to the width direction of the microchannels, and the length q of the short axis of the elliptic microcolumns is (w-d)/n.

9. The method for preparing a micro-chromatography column according to claim 8, wherein: in the width direction of the micro channel, the adjacent n rows of the elliptic micro columns are arranged at equal intervals; or n columns of the elliptical micro-pillars have different pitches, and the pitches gradually decrease along the extending direction of the center of the micro-channel to the side wall of the micro-channel.

10. The method for preparing a micro-chromatography column according to claim 8, further comprising the steps of:

providing a cover plate;

bonding the cover plate to the surface of the substrate, with the cover plate covering the microchannels;

and carrying out scribing treatment on the bonded structure.

Technical Field

The invention belongs to the field of micro-electro-mechanical systems, and relates to a micro-chromatographic column and a preparation method thereof.

Background

The chromatographic column is one of the important components of the gas chromatograph, plays a role in separating mixed gas in the whole system, and the quality of the performance of the chromatographic column directly influences the analysis effect of the whole analysis instrument. The separation effect of the chromatographic column mainly depends on the stationary phase coated on the inner surface of the channel, the adsorption and desorption capacities of different fixed gases are different, so that the flowing speeds of different gas components to be detected in the channel are different, and finally different gas components reach the outlet of the chromatographic column at different time, so that the separation of mixed gas is realized.

Traditional gas chromatographic columns include capillary columns, packed columns and the like, and because the volume is large, a special column incubator is required for heating the traditional gas chromatographic columns, the power consumption of the traditional gas chromatographic columns reaches thousands of watts, and therefore the miniaturization of the gas chromatographic columns is of great importance in order to realize the miniaturization of gas chromatographs.

With the improvement of microelectronic technology, the technology of preparing the micro chromatographic column on the silicon chip is realized, and the problems of large volume, high power consumption and the like of the traditional chromatographic column are solved. Since the volume of the micro-chromatography is small, the surface area of the applicable stationary phase is small, and the separation performance is reduced to some extent, a novel micro-chromatography column structure named as a semi-packed column is proposed, the semi-packed column is a micro-column structure which is implanted in a regular arrangement in a trench of the micro-chromatography column, the design can greatly improve the inner surface area of the micro-chromatography column, but in order to further improve the inner surface area of the semi-packed column, researchers usually adopt a mode of increasing the number of the micro-columns, but the mode can cause the pre-column pressure of the semi-packed column to be greatly increased due to the increase of the number of the micro-columns, so that the gas can well pass through the trench of the micro-chromatography column only by additionally increasing the pre-column pressure, the requirement for carrier gas is increased, and the requirement for the carrier gas needs to be reduced as much as possible in portable application.

Therefore, it is necessary to provide a micro-chromatographic column and a preparation method thereof.

Disclosure of Invention

In view of the above-mentioned shortcomings of the prior art, the present invention is directed to a micro-chromatography column and a method for preparing the same, which is used to solve the problem that it is difficult for the micro-chromatography column to satisfy the coordination between the inner surface area of the column and the pre-column pressure.

To achieve the above and other related objects, the present invention provides a micro-chromatography column comprising:

a substrate;

a microchannel, the microchannel being located in the substrate, the microchannel having a width w and an effective width d;

the elliptic micro-columns are positioned in the micro-channels, n columns of the elliptic micro-columns are arranged at intervals in the width direction of the micro-channels, m rows of the elliptic micro-columns are arranged at intervals in the extending direction of the micro-channels to form an n x m elliptic micro-column array, the long axis direction of the elliptic micro-columns is parallel to the extending direction of the micro-channels, the short axis direction of the elliptic micro-columns is parallel to the width direction of the micro-channels, and the length q of the short axis of the elliptic micro-columns is (w-d)/n.

Optionally, n adjacent columns of the elliptical micro-pillars are arranged at equal intervals in the width direction of the micro-channel.

Optionally, the n columns of elliptical micro-pillars have different pitches along the width direction of the micro-channel, and the pitches gradually decrease along the extension direction of the center of the micro-channel to the side wall of the micro-channel.

Optionally, in the width direction of the microchannel, the pitch of the elliptical micro pillars in the n adjacent columns is smaller than the pitch between the elliptical micro pillars at the edge and the side wall of the microchannel.

Optionally, the width w of the micro channel is 100 μm to 600 μm, the effective width d of the micro channel is 50 μm to 300 μm, the length p of the major axis of the elliptical micro-column is 10 μm to 150 μm, the length q of the minor axis of the elliptical micro-column is 5 μm to 75 μm, and the ratio of the length p of the major axis of the elliptical micro-column to the length q of the minor axis of the elliptical micro-column is 3:2 to 30: 1.

Optionally, the width w of the micro channel is 250 μm, the effective width d of the micro channel is 130 μm, the length p of the major axis of the elliptical micro column is 60 μm, and the length q of the minor axis of the elliptical micro column is 10 μm to 40 μm.

Optionally, the microchannel extends in a serpentine shape; the substrate comprises a silicon substrate, a glass substrate or a ceramic substrate; the micro chromatographic column further comprises a cover plate, the cover plate is bonded on the substrate and covers the micro channel, and the cover plate comprises a glass cover plate, a silicon cover plate or a ceramic cover plate.

The invention also provides a preparation method of the micro chromatographic column, which comprises the following steps:

providing a substrate;

forming a patterned mask layer on the surface of the substrate;

etching the substrate based on the patterned mask layer to form a micro-channel and an elliptical micro-column in the substrate, wherein the micro-channel is located in the substrate, the width of the micro-channel is w, and the effective width of the micro-channel is d; the elliptic microcolumns are positioned in the microchannels, n columns of the elliptic microcolumns are arranged at intervals in the width direction of the microchannels, m rows of the elliptic microcolumns are arranged at intervals in the extending direction of the microchannels to form an n x m elliptic microcolumn array, the long axis direction of the elliptic microcolumns is parallel to the extending direction of the microchannels, the short axis direction of the elliptic microcolumns is parallel to the width direction of the microchannels, and the length q of the short axis of the elliptic microcolumns is (w-d)/n.

Optionally, in the width direction of the microchannel, n adjacent rows of the elliptical micro-pillars are arranged at equal intervals; or n columns of the elliptical micro-pillars have different pitches, and the pitches gradually decrease along the extending direction of the center of the micro-channel to the side wall of the micro-channel.

Optionally, the method further comprises the following steps:

providing a cover plate;

bonding the cover plate to the surface of the substrate, with the cover plate covering the microchannels;

and carrying out scribing treatment on the bonded structure.

As described above, the micro-chromatographic column and the preparation method of the micro-chromatographic column have the following beneficial effects:

according to the micro chromatographic column and the preparation method, the n multiplied by m elliptical micro column array positioned in the micro channel can greatly reduce the area of a quasi-zero flow velocity area formed after the micro column, so that the flow velocity distribution in the column is uniform;

according to the micro chromatographic column and the preparation method, the length q of the short axis of the elliptical micro column can be adjusted while the number of the elliptical micro columns is increased in an nxm elliptical micro column array through a relational expression of q ═ w/n, so that the inner surface area of the column can be effectively improved on the premise of keeping the width w of a micro channel and the effective width d of the micro channel unchanged, the separation performance of the micro chromatographic column can be improved, the problem of pressure rise in front of the column caused by the increase of the number of the micro columns can be effectively solved, and the micro chromatographic column can keep lower pressure in front of the column while effectively increasing the surface area;

according to the micro chromatographic column and the preparation method, the n rows of elliptical micro columns are designed to have different intervals in the width direction of the microchannel, the intervals are gradually reduced in the extending direction from the center of the microchannel to the side wall of the microchannel, and the intervals between the elliptical micro columns positioned at the edge and the side wall of the microchannel are designed to be larger than the intervals between the elliptical micro columns, so that the problem of non-uniform flow rate of carrier gas can be further relieved, and the flow rate distribution in the column is further uniform;

the micro-chromatographic column has simple structure and preparation process, can effectively improve the detection performance of the micro-chromatographic column, can keep lower pressure before the column while increasing the surface area, and enables the flow velocity in the column to be uniformly distributed, thereby improving the efficacy of the micro-chromatographic column, reducing the burden of an air supply system, being beneficial to portable application and enabling the micro-chromatographic column to have wide application prospect.

Drawings

Fig. 1 is a flow chart illustrating a method for preparing a micro-chromatography column provided in a first embodiment of the present invention.

Fig. 2 to 6 are schematic structural diagrams illustrating structures obtained in steps of a method for preparing a micro-chromatography column according to a first embodiment of the present invention.

Fig. 7 is a schematic perspective view of a micro-chromatography column according to a first embodiment of the invention.

Fig. 8 is a schematic top view of the area a in fig. 7.

Fig. 9a to 9c are schematic partial enlarged top structural views of three micro-chromatographic columns provided in the first embodiment.

Fig. 10 is a schematic diagram showing a partially enlarged top view structure of a micro-chromatography column provided in the second embodiment of the present invention.

Description of the element reference numerals

100 substrate

110. Side wall of 120 micro-channel

200 mask layer

201 silicon oxide mask layer

202 photoresist mask layer

300. 310 micro channel

400. 410 elliptic microcolumn

500 cover plate

610 a carrier gas carrying the gas component to be measured

Detailed Description

The embodiments of the present invention are described below with reference to specific embodiments, and other advantages and effects of the present invention will be easily understood by those skilled in the art from the disclosure of the present specification. The invention is capable of other and different embodiments and of being practiced or of being carried out in various ways, and its several details are capable of modification in various respects, all without departing from the spirit and scope of the present invention.

As in the detailed description of the embodiments of the present invention, the cross-sectional views illustrating the device structures are not partially enlarged in general scale for convenience of illustration, and the schematic views are only examples, which should not limit the scope of the present invention. In addition, the three-dimensional dimensions of length, width and depth should be included in the actual fabrication.

For convenience in description, spatial relational terms such as "below," "beneath," "below," "under," "over," "upper," and the like may be used herein to describe one element or feature's relationship to another element or feature as illustrated in the figures. It will be understood that these terms of spatial relationship are intended to encompass other orientations of the device in use or operation in addition to the orientation depicted in the figures. Further, when a layer is referred to as being "between" two layers, it can be the only layer between the two layers, or one or more intervening layers may also be present. As used herein, "between … …" is meant to include both endpoints.

In the context of this application, a structure described as having a first feature "on" a second feature may include embodiments in which the first and second features are formed in direct contact, and may also include embodiments in which additional features are formed in between the first and second features, such that the first and second features may not be in direct contact.

It should be noted that the drawings provided in the present embodiment are only for illustrating the basic idea of the present invention, and the drawings only show the components related to the present invention rather than being drawn according to the number, shape and size of the components in actual implementation, and the type, quantity and proportion of each component in actual implementation may be changed freely, and the layout of the components may be more complicated.

As described in the background art, in order to further increase the column internal surface area of the semi-packed column of the micro chromatography column, when researchers increase the number of micro columns only in the micro channel, it may cause side effects: the pressure before the column of the semi-packed column needs to be increased. This is mainly because simply increasing the number of micro-columns will result in a decrease in the effective width of the micro-channels, i.e. the minimum gas flow path width across the cross-section of the channel perpendicular to the gas flow rate will be reduced, so to achieve the test effect, a greater pre-column pressure needs to be provided to allow the gas to effectively pass through the micro-channels of the micro-chromatography columns, which undoubtedly increases the carrier gas requirement, and in portable applications, the requirement for the carrier gas needs to be reduced as much as possible.

Therefore, in order to solve the problem of coordination between the surface area in the column and the pressure before the column, a novel micro-chromatographic column and a preparation method thereof need to be provided, and the concept of the present invention will be specifically described below with reference to the accompanying drawings and examples.

Example one

As shown in fig. 1, this embodiment provides a method for preparing a micro-chromatography column, which includes the following steps:

providing a substrate;

forming a patterned mask layer on the surface of the substrate;

etching the substrate based on the patterned mask layer to form a micro-channel and an elliptical micro-column in the substrate, wherein the micro-channel is located in the substrate, the width of the micro-channel is w, and the effective width of the micro-channel is d; the elliptic microcolumns are positioned in the microchannels, n columns of the elliptic microcolumns are arranged at intervals in the width direction of the microchannels, m rows of the elliptic microcolumns are arranged at intervals in the extending direction of the microchannels to form an n x m elliptic microcolumn array, the long axis direction of the elliptic microcolumns is parallel to the extending direction of the microchannels, the short axis direction of the elliptic microcolumns is parallel to the width direction of the microchannels, and the length q of the short axis of the elliptic microcolumns is (w-d)/n.

In the preparation method of the micro chromatographic column of the embodiment, by forming the n × m elliptical micro column array located in the micro channel, the area of the quasi-zero flow velocity zone formed after the micro column can be greatly reduced, so that the flow velocity distribution in the column is uniform; further, according to the relation q ═ w-d)/n, in the nxm elliptical micro-column array, the number of the elliptical micro-columns can be increased, and the length q of the short axis of the elliptical micro-columns can be adjusted at the same time, so that the inner surface area of the column can be effectively increased to improve the separation performance of the micro-chromatographic column, and the problem of the pressure rise in front of the column caused by the increase of the number of the micro-columns can be effectively solved, so that the micro-chromatographic column can effectively increase the surface area and keep the lower pressure in front of the column, the flow velocity distribution in the column is uniform, the efficacy of the micro-chromatographic column is improved, the burden of an air supply system is reduced, the portable application is facilitated, and the micro-chromatographic column has a wide application prospect.

Specifically, referring to fig. 2 to 6, the following describes the preparation of the micro-chromatography column in this embodiment with reference to the drawings. Fig. 7 is a schematic perspective view of the micro-chromatography column formed in this embodiment, fig. 8 is a schematic enlarged top-view structure of the region a in fig. 7, fig. 2 to 5 can be understood as schematic partial enlarged cross-sectional structures taken along C-C' in fig. 7, and fig. 6 is a schematic structural view of the micro-chromatography column with the cover plate.

First, referring to fig. 2, a substrate 100 is provided, and a patterned mask layer 200 is formed on a surface of the substrate 100.

As an example, the substrate 100 may include a silicon substrate, a glass substrate, or a ceramic substrate; the mask layer 200 may include one or a combination of a silicon oxide mask layer, a silicon nitride mask layer, and a photoresist mask layer.

Specifically, the types of the substrate 100 and the mask layer 200 are not limited thereto, and may be selected according to needs, and in this embodiment, the substrate 100 is a silicon substrate, and the mask layer 200 is a stack of a silicon oxide mask layer 201 and a photoresist mask layer 202 covering the substrate 100, but is not limited thereto.

As an example, the step of forming the patterned mask layer 200 on the surface of the substrate 100 may include the steps of:

forming a mask stack comprising the silicon oxide mask layer 201 and the photoresist mask layer 202 on the surface of the substrate 100;

patterning the photoresist mask layer 202 by adopting photoetching and etching processes to obtain a photoresist etching window;

and etching to pattern the silicon oxide mask layer 201 based on the patterned photoresist mask layer 202 to obtain a silicon oxide etching window.

In the present embodiment, the patterned silicon oxide mask layer 201 is obtained by photolithography and BOE etchant etching, and the forming process of the silicon oxide mask layer 201 is not limited thereto, and referring to fig. 3 and 4, the shape and position of the micro-channel 300 and the elliptical micro-pillar 400 to be formed later can be defined by the silicon oxide etching window.

Next, referring to fig. 4, fig. 7 and fig. 8, the substrate 100 is etched based on the patterned mask layer 200 to form a micro channel 300 and an elliptical micro pillar 400 in the substrate 100, wherein the micro channel 300 is located in the substrate 100, the width of the micro channel 300 is w, and the effective width of the micro channel 300 is d; the elliptical micro-pillars 400 are positioned in the micro-channel 300, n columns of the elliptical micro-pillars 400 are arranged at intervals in the width direction of the micro-channel 300, m rows of the elliptical micro-pillars 400 are arranged at intervals in the extension direction of the micro-channel 300 to form an n × m elliptical micro-pillar array, the major axis direction of the elliptical micro-pillars 400 is parallel to the extension direction of the micro-channel 300, the minor axis direction of the elliptical micro-pillars 400 is parallel to the width direction of the micro-channel 300, and the minor axis length q of the elliptical micro-pillars 400 is (w-d)/n.

Specifically, in the present embodiment, the exposed substrate 100 is etched based on a Deep Reactive Ion Etching (DRIE) technique to form the micro-channels 300 and the elliptical micro-pillars 400 in the substrate 100, but the etching method is not limited thereto, and may be adaptively selected as needed.

In this embodiment, by the n × m elliptical micro-pillar array located in the micro-channel 300, the area of the "quasi-zero flow velocity zone" formed behind the micro-pillar can be greatly reduced, so that the flow velocity distribution in the pillar is uniform; and q is (w-d)/n relational expression, the minor axis length q of the elliptical micro-column 400 can be adjusted while increasing the number of the elliptical micro-columns 400, so that the inner surface area of the column can be effectively increased to improve the separation performance of the micro-chromatographic column 400 and simultaneously the problem of increased pressure in front of the column due to the increase of the number of the micro-columns can be effectively solved on the premise of keeping the width w of the micro-channel 300 and the effective width d of the micro-channel 300 unchanged, so that the micro-chromatographic column 400 can maintain lower pressure in front of the column while effectively increasing the surface area, thereby improving the efficacy of the micro-chromatographic column 400, reducing the burden of an air supply system, facilitating portable application and enabling the micro-chromatographic column to have wide application prospects.

As an example, n adjacent columns of the elliptical micro pillars 400 are arranged at equal intervals in the width direction of the micro channel 300.

Specifically, in order to reduce the process complexity, when patterning the mask 200, patterned etching windows arranged at equal intervals may be formed along the width direction of the micro channel 300 according to needs, but the present invention is not limited thereto, and in another embodiment, patterned etching windows arranged at unequal intervals may also be formed along the width direction of the micro channel 300 according to needs, which will not be described herein.

Referring to fig. 8, in the present embodiment, n adjacent rows of the elliptical micro pillars 400 have an equal spacing s along the width direction of the micro channel 300, and m adjacent rows of the elliptical micro pillars 400 have an equal spacing t along the extension direction of the micro channel 300. The values relating to the spacing s and the spacing t are not overly limited herein.

As an example, the pitch S of the elliptical micro pillars 400 of the adjacent n columns in the width direction of the micro channel 300 is smaller than the pitch S between the elliptical micro pillars 400 at the edge and the sidewall 110 of the micro channel 300, i.e., S > S, to provide a uniform flow rate in the micro channel 300.

Illustratively, the width w of the microchannel 300 is 100 to 600 μm, the effective width d of the microchannel 300 is 50 to 300 μm, the length p of the major axis of the elliptic microcolumn 400 is 10 to 150 μm, the length q of the minor axis of the elliptic microcolumn 400 is 5 to 75 μm, and the ratio of the length p of the major axis of the elliptic microcolumn 400 to the length q of the minor axis of the elliptic microcolumn 400 is 3:2 to 30: 1.

Specifically, the width w of the micro-channel 300 may be 100 μm, 200 μm, 300 μm, 400 μm, 500 μm, 600 μm, etc., as required, the effective width d of the micro-channel 300 may be 50 μm, 100 μm, 150 μm, 200 μm, 250 μm, 300 μm, etc., the length p of the major axis of the elliptic micro-column 400 may be 10 μm, 50 μm, 100 μm, 120 μm, 150 μm, etc., the length q of the minor axis of the elliptic micro-column 400 may be 5 μm, 10 μm, 30 μm, 60 μm, 75 μm, etc., and the ratio of the length p of the major axis of the elliptic micro-column 400 to the length q of the minor axis of the elliptic micro-column 400 may be 3:2 to 30:1, such as 3:2, 2:1, 3:1, 4:1, 10:1, 20:1, 25:1, 30:1, etc.

As an example, the width w of the microchannel 300 may be 250 μm, the effective width d of the microchannel 300 may be 130 μm, the length p of the major axis of the elliptical micro pillar 400 may be 60 μm, and the length q of the minor axis of the elliptical micro pillar 400 may be 10 μm to 40 μm.

Specifically, referring to fig. 7 in this embodiment, a microchannel 300 of the micro chromatography column contains a 6 × 12 elliptical micro column array, and the elliptical micro columns 400 are regularly distributed periodically. It should be noted that, in fig. 7, n is 6, m is 12, 5 sub-microchannels with S width are formed in the microchannel 300, and 2 sub-microchannels with S width, that is, d is 5S +2S, as shown in fig. 8, in fact, the number of columns, rows, and sizes of the elliptical micro-pillars 400 may be selected according to actual needs. As shown in fig. 9a to 9c, three types of micro-chromatographic columns with channel width w of 250 μm, effective width d of 130 μm, and n of 6, 4, and 8 are schematically shown, wherein the minor axes are 20 μm, 30 μm, and 15 μm, respectively, and the length ratios of the center distance between two adjacent elliptic micro-columns to the minor axis are respectively: 37:20, 9:5 and 29:15, and the length ratio of the center distance to the short axis of two adjacent elliptic micro-columns is generally less than 2.5, but the structure of the micro-chromatographic column is not limited to the above.

In the micro-column of this example, according to the relationship q ═ w-d/n, in the n × m elliptic micro-column array, the minor axis length q of the elliptical micro-pillars 400 may be adjusted while increasing the number of the elliptical micro-pillars 400, so as to effectively increase the inner surface area of the column to improve the separation performance of the micro chromatographic column on the premise of keeping the width w of the micro channel 300 and the effective width d of the micro channel 300 unchanged, meanwhile, the problem of the increase of the pressure in front of the column caused by the increase of the number of the micro-columns can be effectively solved, so that the micro-chromatographic column can effectively increase the surface area and simultaneously keep lower pressure in front of the column, and the flow velocity distribution in the column is uniform, thereby improving the efficacy of the micro chromatographic column, reducing the burden of an air supply system, being beneficial to portable application and leading the micro chromatographic column to have wide application prospect.

As an example, the micro-channel 300 may be formed to extend in a serpentine shape, but in other examples, the micro-channel 300 may also be formed to extend in any extending manner in the substrate 100, such as a polygonal line extension, a U-shaped extension, a spiral extension, etc., which is not limited herein.

As an example, the method further comprises the following steps:

providing a cover plate 500;

bonding the cover plate 500 to the surface of the substrate 100, with the cover plate 500 covering the microchannels 300;

and carrying out scribing treatment on the bonded structure.

As an example, the cover plate 500 may include a glass cover plate, a silicon cover plate, or a ceramic cover plate, and preferably, in the present embodiment, the cover plate 500 is a double-side polished glass cover plate.

Specifically, referring to fig. 6, the cover plate 500 may be bonded to the surface of the substrate 100 by using an anodic bonding process, wherein the bonding process conditions may be selected according to the needs, and are not limited herein. If a plurality of independent micro-chromatographic columns are formed in the substrate 100, after the cover plate 500 is bonded to the surface of the substrate 100, the bonded structure may be subjected to dicing treatment to obtain a plurality of micro-chromatographic columns, so as to improve the production efficiency.

Then, capillary tubes (not shown) can be respectively installed at the inlet end and the outlet end of the prepared micro-chromatographic column for performing related tests, which are not described herein again.

Referring to fig. 7 to 9c, the present embodiment further provides a micro-chromatography column, including:

a substrate 100;

a microchannel 300, the microchannel 300 being located in the substrate 100, the microchannel 300 having a width w, the microchannel 300 having an effective width d;

the elliptic micro-pillars 400 are positioned in the micro-channel 300, n columns of the elliptic micro-pillars 400 are arranged at intervals in the width direction of the micro-channel 300, m rows of the elliptic micro-pillars 400 are arranged at intervals in the extension direction of the micro-channel 300 to form an n × m elliptic micro-pillar array, the major axis direction of the elliptic micro-pillars 400 is parallel to the extension direction of the micro-channel 300, the minor axis direction of the elliptic micro-pillars 400 is parallel to the width direction of the micro-channel 300, and the minor axis length q of the elliptic micro-pillars 400 is (w-d)/n.

In the micro chromatographic column of the present embodiment, through the n × m elliptical micro column array located in the micro channel 300, the area of the "quasi-zero flow velocity zone" formed after the micro column can be greatly reduced, so that the flow velocity distribution in the column is uniform; further, according to the relation q ═ w-d)/n, in the nxm elliptical micro-column array, the number of the elliptical micro-columns 400 can be increased, and the length q of the short axis of the elliptical micro-columns 400 can be adjusted at the same time, so that the inner surface area of the columns can be effectively increased on the premise that the width w of the micro-channel 300 and the effective width d of the micro-channel 300 are not changed, the separation performance of the micro-chromatographic columns can be improved, and the problem of the increase of the pressure in front of the columns caused by the increase of the number of the micro-columns can be effectively solved, so that the micro-chromatographic columns can effectively increase the surface area and keep the lower pressure in front of the columns, the flow velocity distribution in the columns is uniform, the efficacy of the micro-chromatographic columns is improved, the burden of an air supply system is reduced, the portable application is facilitated, and the micro-chromatographic columns have a.

The micro-chromatographic column can be prepared by the preparation method, but is not limited to the preparation method.

As an example, n adjacent columns of the elliptical micro pillars 400 are arranged at equal intervals in the width direction of the micro channel 300 to reduce process complexity.

As an example, the pitch of the elliptical micro pillars 400 of the adjacent n columns in the width direction of the micro channel 300 is smaller than the pitch between the elliptical micro pillars 400 at the edge and the sidewall 110 of the micro channel 300, i.e., S > S, to provide a uniform flow rate in the micro channel 300.

Illustratively, the width w of the microchannel 300 is 100 μm to 600 μm, such as 100 μm, 200 μm, 300 μm, 400 μm, 500 μm, 600 μm, and the like; the effective width d of the micro-channel 300 is 50 μm to 300 μm, such as 50 μm, 100 μm, 150 μm, 200 μm, 250 μm, 300 μm, etc.; the length p of the major axis of the elliptic microcolumn 400 is 10 μm to 150 μm, such as 10 μm, 50 μm, 100 μm, 120 μm, 150 μm, etc.; the length q of the minor axis of the elliptic microcolumn 400 is 5 μm to 75 μm, such as 5 μm, 10 μm, 30 μm, 60 μm, 75 μm, etc.; the ratio of the length p of the major axis of the elliptical micro-column 400 to the length q of the minor axis of the elliptical micro-column 400 is 3:2 to 30:1, such as 3:2, 2:1, 3:1, 4:1, 10:1, 20:1, 25:1, 30:1, but not limited thereto.

As an example, the width w of the micro-channel 300 is 250 μm, the effective width d of the micro-channel 300 is 130 μm, the length p of the major axis of the elliptical micro-pillar 400 is 60 μm, and the length q of the minor axis of the elliptical micro-pillar 400 is 10 μm to 40 μm, as shown in fig. 9a to 9c, but not limited thereto.

As an example, the micro-channel 300 extends in a serpentine shape, but in other examples, the micro-channel 300 may also be formed to extend in any extending manner in the substrate 100, such as a polygonal line extension, a U-shaped extension, a spiral extension, etc., which is not limited herein.

As an example, the substrate 100 may include a silicon substrate, a glass substrate, or a ceramic substrate; the micro chromatography column may further include a cover plate 500, the cover plate 500 being bonded to the substrate 100 and covering the micro channels 300, the cover plate 500 may include a glass cover plate, a silicon cover plate, or a ceramic cover plate, but the kinds of the substrate 100 and the cover plate 500 are not limited thereto.

Example two

Referring to fig. 10, the present embodiment further provides a micro-chromatography column and a preparation method thereof, and the difference between the present embodiment and the first embodiment is as follows: the n columns of elliptical micro-pillars 410 have different pitches along the width direction of the micro-channel 310, and the pitches gradually decrease along the center of the micro-channel 310 toward the extension direction of the side wall 120 of the micro-channel 310, i.e., s ' 3 < s ' 2 < s ' 1.

Specifically, since the carrier gas 610 carrying the gas to be measured has a greater gas flow rate in the central region than in the edge region when entering the micro-chromatography column, it is difficult to provide a uniform flow rate of the gas into the micro-chromatography column. In the embodiment, the n rows of elliptical micro-columns 410 are designed to have different pitches in the width direction of the micro-channel 310, and the pitches gradually decrease in the extending direction from the center of the micro-channel 310 to the side wall 120 of the micro-channel 310, so that the problem of non-uniform flow rate of the carrier gas 610 can be further alleviated, the flow rate distribution in the columns is further uniform, the efficacy of the micro-chromatography column can be improved, the burden of a gas supply system is reduced, the portable application is facilitated, and the micro-chromatography column has a wide application prospect.

Wherein the width of the micro channel 310 is w ', and the effective width of the micro channel 310 is d', d ═ S '1 +2 (S' + S '2 + S' 3); the column number n ' and the row number m ' of the elliptical micro-pillars 410 located in the micro-channel 310, the length q ' of the short axis and the length p ' of the long axis of the elliptical micro-pillars 410, the distances S ', S ' 1, S ' 2, S ' 3, and t ', and the materials and the preparation methods of the micro-chromatographic pillars can all refer to the first embodiment, which is not described herein.

In summary, the micro-chromatographic column and the preparation method of the invention can greatly reduce the area of the quasi-zero flow velocity zone formed behind the micro-column by the n × m elliptical micro-column array positioned in the micro-channel, so that the flow velocity distribution in the column is uniform; by the relational expression of (w-d)/n, in an nxm elliptical micro-column array, the number of elliptical micro-columns can be increased, and the length q of the short axis of the elliptical micro-columns can be adjusted at the same time, so that the inner surface area of the column can be effectively improved on the premise of keeping the width w of a micro-channel and the effective width d of the micro-channel unchanged, the separation performance of the micro-chromatographic column can be improved, and the problem of pressure rise in front of the column caused by the increase of the number of the micro-columns can be effectively solved, so that the micro-chromatographic column can keep lower pressure in front of the column while effectively increasing the surface area; by designing n columns of elliptical micro-pillars to have different pitches in the width direction of the microchannel, wherein the pitches gradually decrease in the extending direction from the center of the microchannel to the side wall of the microchannel, and designing the pitches between the elliptical micro-pillars positioned at the edge and the side wall of the microchannel to be larger than the pitches between the elliptical micro-pillars, the problem of non-uniform flow velocity of carrier gas can be further alleviated, and the flow velocity distribution in the pillars is further uniform; the method can effectively improve the detection performance of the micro chromatographic column, can keep lower pre-column pressure while increasing the surface area, and enables the flow velocity distribution in the column to be uniform, thereby improving the efficacy of the micro chromatographic column, reducing the burden of an air supply system, being beneficial to portable application and enabling the micro chromatographic column to have wide application prospect.

The foregoing embodiments are merely illustrative of the principles and utilities of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or change the above-mentioned embodiments without departing from the spirit and scope of the present invention. Accordingly, it is intended that all equivalent modifications or changes which can be made by those skilled in the art without departing from the spirit and technical spirit of the present invention be covered by the claims of the present invention.