CN217909070U - Pressure variable pore structure for extraction column and extraction column - Google Patents

Abstract

The utility model provides a press and become pore structure for extraction post, including last middle and lower three-layer, from last to being elastic soft board, polymer filter membrane and support orifice plate down in proper order. Still provide an extraction column with press and become hole to the inflow end of mobile phase is as the upper end, from last to down the extraction column is including the column cap, front end cap, column pipe, the inside packing of column pipe that connect gradually have stationary phase, terminal cap and column cap, the front end of front end cap is equipped with press and become hole structure. The utility model provides an extraction column with press and become pore structure, has the double-deck and presses and become the characteristics, and the first layer can intercept rigid particle impurity, and the second floor can intercept small molecule material, combines liquid chromatogram's back washing function to promote extraction column's life.

Description

Pressure variable pore structure for extraction column and extraction column

Technical Field

The utility model belongs to the liquid chromatography field, concretely relates to press and become pore structure and an extraction post for extracting post.

Background

In solid phase extraction systems, on-line processing of samples is often performed using a chromatography column, typically an extraction column for sample processing. In two-dimensional liquid chromatography detection, an extraction column is mainly used for primary separation, purification and concentration of a sample; in this process, the extraction column is subject to contamination from various impurities in the sample, which tend to accumulate at the inlet end, resulting in high pressure, which severely affects the useful life of the extraction column.

The structure of the extraction column generally comprises a column tube, a sieve plate and a column cap, wherein the sieve plate in the column cap is a stainless steel sintered mesh plate with the pore diameter of 0.5-3 mu m. The mobile phase flows through the chromatographic column and is generally intercepted by the sieve plate firstly, but because a large amount of impurities exist in the sample, particularly the protein in the biological sample is subjected to a mass aggregation phenomenon after being intercepted by the sieve plate, the degree of sieve plate blockage is more and more along with the increase of the sample feeding times and the longer time of the chromatographic column, which is the most common problem of the modern liquid chromatographic column. The extraction column is usually subjected to a larger sample volume than a conventional chromatographic column, and the extraction column is usually subjected to a sample volume of 100. Mu.l or more, so that the extraction column is more likely to be clogged. The service life of an extraction column for treating sewage treatment or biomass samples generally hardly exceeds 200 needles.

The existing solution is to perform ultrasonic cleaning on the column cap of the extraction column or replace column head filler to repair the column head, but the existing solution needs high specialization and has limited capability of solving the problem. Or adding a filter to prevent the chromatographic column from being polluted, for example, CN91210781.2 discloses a high performance liquid chromatographic column with a protective column, which is directly connected with an analytical column, and a filter sieve plate is added on the column head of the protective column to replace the filter which is usually separated into two bodies with the chromatographic column. This is the method of external addition of structure or external cleaning employed.

The applicant has already obtained a patent for a liquid chromatograph with an on-line cleaning function (application No. 201410705067.5) which is mainly directed to the on-line cleaning of the first and middle columns of a two-dimensional liquid chromatograph, with a reverse cleaning function. Of course, this is only one specific chromatographic system. The column may be cleaned either on-line or off-line.

Therefore, it is necessary to develop an extraction column, which solves the problem of the blockage of the extraction column by a simple method and prolongs the service life of the extraction column.

SUMMERY OF THE UTILITY MODEL

The utility model discloses a be not enough to prior art, the purpose of the utility model is to research and develop an extraction column with press and become the hole, can be easier go extraction column entry end impurity reverse cleaning to promote the life of extraction column.

The technical scheme of the utility model is that:

a pressure-variable pore structure for an extraction column comprises an upper layer, a middle layer and a lower layer, wherein an elastic soft plate, a polymer filter membrane and a support pore plate are sequentially arranged from top to bottom.

Preferably, the flexible soft plate comprises a fixed ring and a sieve plate positioned in the fixed ring.

Preferably, the polymeric filter membrane is made of a material capable of resisting organic and acid-base reagents, and may be polyether sulfone resin, polypropylene or the like.

Preferably, the sieve plate is made of polyethylene or polypropylene.

Preferably, the thickness of the elastic soft plate is 0.5mm-8mm, the pore diameter is 2 μm-30 μm, the thickness of the macromolecular filter membrane is 0.1-2mm, and the substance with the molecular weight larger than 5000Da can be intercepted.

The utility model provides an extraction column with press and become hole to the inflow end of mobile phase is as the upper end, from last to down the extraction column is including the column cap, front end cap, column pipe, terminal cap and the column cap that connect gradually, the front end of front end cap is equipped with above-mentioned press and becomes hole structure.

Preferably, the column head is provided with a hole for flowing in or flowing out of the mobile phase.

Preferably, the column tube is filled with a stationary phase.

Preferably, the column tube inlet end is provided with a front end column cap, the column tube outlet end is provided with a tail end column cap, the column tube inlet end and the column tube outlet end are arranged in the column head, internal threads are arranged in the column head, and the column tube is connected with the column head through threads.

Preferably, the materials of the column tube and the column head are stainless steel.

The utility model discloses a be equipped with in the column cap of entry end and press and become pore structure, the extraction column is about the general 2MPa of background pressure that one-dimensional mobile phase corresponds, is not enough to form the high pressure, when the supplementary mobile phase of high velocity of flow gets into, forms the high pressure, generally reaches more than 10MPa, and elasticity soft board shrink aperture downwards diminishes, intercepts filtering particles, and more thin impurity is intercepted by the polymer film and is filtered, and the support orifice plate supports elasticity soft board and polymer film; during on-line and off-line reverse cleaning, the pressure is reduced, the elastic soft plate is deformed and expanded, and impurities intercepted by the organic polymer filter membrane and the elastic soft plate are reversely eluted and discharged.

Compared with the prior art, the utility model has the advantages that:

the utility model discloses an extraction post has the double-deck characteristics of pressing to become, and first layer can intercept rigid particle impurity, and the second floor can intercept small molecule material, and when online and off-line reverse cleaning, pressure reduction, elasticity soft board take place the deformation expansion, and the impurity of organic polymer filtration membrane and elasticity soft board interception is discharged by reverse elution to promote the life of extraction post, can reach more than 1000 needles through test life.

The detailed structure of the present invention will be further described with reference to the accompanying drawings and the detailed description.

Drawings

FIG. 1 is a schematic view showing a disassembled structure of an extraction column having a pressure-variable pore;

FIG. 2 is a schematic cross-sectional view of an extraction column having a pressure-variable pore;

FIG. 3 is a schematic top view of a pressure-variable aperture soft plate;

FIG. 4 is a graph comparing the change of peak shape during the use of 1000 needles in an extraction column having a pressure swing pore according to the example;

FIG. 5 is a comparison of peak patterns after 200 pins were used for the senior SPE pre-treatment column (no pressure-swing pore structure, other structures are consistent);

table 1 is a pressure comparison table of a pressure-variable pore extraction column and a senior SPE pretreatment column;

wherein, 1 is column cap, 2 is high molecular filter membrane, 3 is elastic soft board, 4 is front end column cap, 5 is column tube, 6 is end column cap, 7 is fixed phase, 8 is support pore plate, 9 is fixed ring, 10 is sieve plate.

Detailed Description

As shown in fig. 1-2: an extraction column with pressure-variable pores takes the inflow end of a mobile phase as the upper end, the extraction column comprises a column cap 1, a front-end column cap 4, a column tube 5, a tail-end column cap 6 and a column cap 1 which are sequentially connected from top to bottom, and the front end of the front-end column cap 4 is sequentially provided with an elastic soft plate 3, a polymer filter membrane 2 and a support pore plate 8 from top to bottom (the elastic soft plate 3, the polymer filter membrane 2 and the support pore plate 8 form a brand-new pressure-variable pore structure); a hole for flowing in or flowing out of the mobile phase is arranged in the column head 1; the column tube 5 is filled with a stationary phase 7; the inlet end of the column tube 5 is provided with a front column cap 4, the outlet end of the column tube 5 is provided with a tail column cap 6, the inlet end of the column tube is arranged in a column head 1, internal threads are arranged in the column head, the outlet end of the column tube is arranged in the column head (the column head at the lower end), internal threads are arranged in the column head, and the column tube is connected with the column head through threads.

Preferably, the elastic soft plate consists of a fixed ring and a sieve plate, and the fixed ring is made of polyether-ether-ketone. The material has the characteristics of high strength, low dissolution and the like.

Preferably, the material of the polymer filter membrane is a fluorine-containing polymer material, and the material has high strength, chemical resistance and thermal stability and has a thickness of 2mm.

The support orifice plate can be stainless steel support orifice plate, perhaps supports the orifice plate and comprises PEEK circle and sieve, and PEEK encloses the material and is polyetheretherketone, and the sieve material is polyethylene, and this material has high strength and dissolves out the characteristic such as with ground, the material of column casing and column cap is the stainless steel.

The thickness of the elastic soft plate 3 is 2mm, the aperture is 5 μm, and the thickness of the polymer filter membrane 2 is 0.5mm.

The working principle is as follows: after a blood sample with a complex matrix is subjected to protein precipitation treatment, the blood sample enters an extraction column along with a liquid chromatography mobile phase, under the action of a large-flow-rate auxiliary mobile phase, the pores of a first layer of elastic soft plate shrink, impurities with large molecular weight in the sample are intercepted when passing through the elastic soft plate, substances with medium and small molecular weights pass through a pressure-variable pore filter plate and then are intercepted and filtered for the second time when passing through a high-molecular filter membrane, finally, a measured object with small molecular weight and part of impurities in the sample enter an extraction column stationary phase through a second-stage pressure-variable pore soft plate and an anti-blocking filter cap, the measured object is primarily separated from the sample under the chromatographic action of the extraction column immobilization, flows into a pipeline through an outlet filter cap, and enters other separation systems or detection systems; after the complex sample treatment is completed for many times or once, off-line or on-line, the extraction column with the pressure variable pore block can reversely use the flow with the elution strength to reversely clean the extraction column, and at the moment, the impurities intercepted by the organic polymer filter membrane and the elastic soft plate are discharged, so that the self-purification of the extraction column is completed.

The extraction column with pressure-variable pores is compared and tested with a conventional extraction column (without a pressure-variable pore structure) in a two-dimensional liquid chromatography system, wherein a test sample contains a levetiracetam biological sample, a detector is Shimadzu SPD-20A, the wavelength is 245nm, a mobile phase is 4% methanol (1 mmol phosphate, pH = 3.2), the flow rate is 1.0mL/min, an auxiliary mobile phase is water, the auxiliary flow rate is 0.5mL/min, the auxiliary time length is 0.5min, the column temperature is 40 ℃, and the sample injection amount is 100 mu L; the extraction column with the pressure-variable pores still has a good peak shape after the test of 200 pins, the pressure is kept stable, and the extraction column can bear the impact of 1000 pins, as shown in figure 4, after the test of 200 pins (without the pressure-variable pore structure, the other structures are consistent), the peak shape is widened as shown in figure 5, meanwhile, the pressure is gradually increased, and the specific pressure performance indexes are shown in table 1.

TABLE 1 pressure Performance index

The above description is a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto, and any person skilled in the art can substitute or change the technical solution of the present invention and its concept within the technical scope of the present invention.

Claims (9)

1. A pressure-variable pore structure for an extraction column is characterized by comprising an upper layer, a middle layer and a lower layer, wherein the upper layer, the middle layer and the lower layer are sequentially provided with an elastic soft plate (3), a polymer filter membrane (2) and a supporting pore plate (8) from top to bottom; the flexible soft plate (3) comprises a fixed ring (9) and a sieve plate (10) positioned in the fixed ring.

2. The pressure-variable pore structure for the extraction column as claimed in claim 1, wherein the polymeric filter membrane (2) is made of fluorine-containing polymeric material, which can resist organic and acid-base reagents.

3. A pressure-variable pore structure for an extraction column as claimed in claim 1, wherein the sieve plate (10) is made of polyethylene or polypropylene.

4. A pressure-variable pore structure for an extraction column as claimed in claim 1, wherein the thickness of the flexible sheet (3) is 0.5mm-8mm, the pore diameter is 2 μm-30 μm, the thickness of the polymeric filter membrane (2) is 0.1-2mm, and the material with molecular weight larger than 5000Da can be intercepted.

5. An extraction column with pressure-variable pores, which takes the inflow end of a mobile phase as the upper end and comprises a column cap (1), a front end column cap (4), a column tube (5), a tail end column cap (6) and a column cap (1) which are sequentially connected from top to bottom, and is characterized in that the front end of the front end column cap (4) is provided with the pressure-variable pore structure as claimed in any one of claims 1 to 4.

6. A pressure swing pore extraction column as claimed in claim 5, wherein the column head (1) is provided with holes for the inflow or outflow of the mobile phase.

7. A pressure-variable pore extraction column as claimed in claim 5, characterized in that the column tube (5) is filled with a stationary phase (7) inside.

8. A pressure-variable pore extraction column as claimed in claim 5, characterized in that the inlet end of the column tube (5) is provided with a front end column cap (4), the outlet end of the column tube (5) is provided with a tail end column cap (6), the inlet end and the outlet end of the column tube (5) are arranged in the column head (1), the column head (1) is internally provided with internal threads, and the column tube and the column head are connected through threads.

9. The extraction column with pressure-variable pores as claimed in claim 5, wherein the column tube (5) and the column head (1) are made of stainless steel.

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