KR102816814B1 - System for simultaneous separation and concentration of multiple samples - Google Patents

Abstract

The present invention provides a system for separating and concentrating multiple samples, comprising: a porous substrate; a hydrophobic region in which a hydrophobic material is coated in a pattern shape on one surface of the porous substrate; and a hydrophilic region that provides a plurality of sample movement passages separated by the hydrophobic pattern; and wherein the hydrophilic region includes absorbent pads attached to both sides in the direction of movement of the sample, a conductive ink layer formed perpendicular to the direction of movement of the sample between the absorbent pads and the hydrophobic pattern, and one or more selective ion permeable portions formed adjacent to the conductive ink layer.
The system according to the present invention can simultaneously concentrate multiple types of samples at a constant speed within a short period of time by forming a conductive ink layer perpendicular to the direction of sample movement and applying a parallel electric field.

Description

{SYSTEM FOR SIMULTANEOUS SEPARATION AND CONCENTRATION OF MULTIPLE SAMPLES}

The present invention relates to a system for simultaneous separation and concentration of multiple samples.

In order to analyze the components in a sample, processes such as separation and purification are required, and a sample concentration process may be necessary to increase the detection sensitivity of the target component.

For example, trace components in a sample can be extracted using an organic solvent, buffer solution, or aqueous solution, and then concentrated by injecting nitrogen gas into the extracted components using a concentration device such as TurboVap (manufactured by Biotage). However, this concentration method has the inconvenience of requiring a long concentration time, a large volume, and continuous injection of nitrogen gas.

Meanwhile, Korean Patent Publication No. 10-2019-0020915 discloses a device that separates and concentrates a sample by applying voltage to a fluid passage on continuous surfaces that are folded by folding the paper, thereby utilizing electrophoretic characteristics and ion concentration polarization. Although this concentration method has the effect of concentrating a target substance in a specific area, it is difficult to perform high-throughput screening of ion concentration polarization when the paper is folded, making it difficult to set concentration conditions, and requires a separate member to fix the folded paper.

Therefore, a technology that can concentrate multiple samples more efficiently is required.

The purpose of the present invention is to provide a system capable of efficiently separating and concentrating multiple samples simultaneously.

According to one aspect of the present invention, there is provided a porous substrate; a hydrophobic region in which a hydrophobic material is coated in a pattern shape on one surface of the porous substrate; and a hydrophilic region provided with a plurality of sample movement passages separated by the hydrophobic pattern.

A system for separating and concentrating multiple samples is provided, wherein the hydrophilic region includes an absorbent pad attached to both sides in the direction of movement of the sample, a conductive ink layer formed perpendicular to the direction of movement of the sample between the absorbent pad and the hydrophobic pattern, and at least one selective ion permeable portion formed adjacent to the conductive ink layer.

Additionally, the present invention provides a method for separating and concentrating multiple samples using the system, the method comprising:

(S1) a step of injecting a sample into each of the plurality of sample movement passages formed in the hydrophilic region of the system;

(S2) a step of injecting a buffer solution into the absorption pad of the above system; and

(S3) A step of applying voltage by contacting an external electrode to the conductive ink layer of the system to perform separation and concentration of the injected sample.

The system according to the present invention can simultaneously concentrate multiple types of samples at a constant speed within a short period of time by forming a conductive ink layer perpendicular to the direction of sample movement and applying a parallel electric field.

Figure 1 schematically illustrates the structure of a separation and concentration system according to one embodiment of the present invention.
Figures 2a and 2b show comparisons of voltage application and simultaneous concentration results for multiple samples according to examples and comparative examples of the present invention, respectively.
Figure 3 shows the peak intensity before and after concentration of multiple samples according to an embodiment of the present invention.

Hereinafter, the terms or words used in this specification and claims should not be interpreted as limited to their usual or dictionary meanings, and should be interpreted as meanings and concepts that conform to the technical idea of the present invention based on the principle that the inventor can appropriately define the concept of the term in order to explain his or her own invention in the best manner.

One embodiment of the present invention relates to a system capable of separating and concentrating multiple samples simultaneously.

FIG. 1 schematically illustrates the structure of a separation and concentration system (1) according to one embodiment of the present invention. The system (1) may include a porous substrate (100), a hydrophobic region (110) and a hydrophilic region (120) formed on the substrate, an absorption pad (121) provided in the hydrophilic region, a conductive ink layer (122), and a selective ion permeation portion (123).

The above porous substrate may be composed of a material that facilitates the adsorption or penetration of hydrophobic substances as the liquid moves by capillary action, and may be, for example, hydrophilic paper or cellulose material. Among these, paper can be advantageously used because the liquid moves smoothly without a separate external power source due to its fiber structure.

In one embodiment of the present invention, the size and shape of the porous substrate can be appropriately set as needed without any special limitation. As one example, the porous substrate can have a length of 30 to 45 mm and a width of 20 to 30 mm.

The hydrophobic region (110) may be formed by coating a hydrophobic material in a pattern shape on one surface of the porous substrate (100), and serves to prevent adsorption of the sample to be processed and to distinguish the movement path of the sample. The hydrophobic material may be an alcohol fatty acid ester such as wax, but is not limited thereto.

In one embodiment of the present invention, the hydrophobic region may occupy 30 to 70% of the total area of the porous substrate.

The hydrophilic region (120) is a region excluding a pattern formed of a hydrophobic material on the porous substrate (100), and provides a passage through which a sample or buffer moves or is stored. The passage through which a sample moves in the hydrophilic region (120) may be provided as a plurality of multi-channels by being separated by hydrophobic patterns, and the number thereof is not particularly limited. For example, as illustrated in FIG. 1, when a hydrophobic pattern is formed on the porous substrate (100) in two parts, a border and a center, three sample movement passages may be provided around the center patterns.

The above absorption pad (121) is attached to both sides in the direction of movement of the sample in the hydrophilic region (120) of the porous substrate (100), and can hold a sample or buffer. In general, in the case of sample separation using the capillary phenomenon, the buffer throughput is only on the order of ㎕, and the buffer begins to evaporate within a short period of time (e.g., 3 minutes). However, by using the absorption pad, the buffer throughput is increased to the ㎖ scale, and thus the porous substrate can be sufficiently saturated with the buffer to perform stable sample separation. If the absorption pad is not used, it takes less than 3 minutes for the aqueous buffer to begin to evaporate, making it difficult to maintain a stable current flow.

In one embodiment of the present invention, the absorbent pad may be attached in a size occupying 5 to 20% of the total area of the porous substrate. In addition, the absorbent pad may be made of fibers having an OH functional group, such as cellulose fibers, gelatin fibers, starch fibers, or a mixture of two or more thereof, and may have a length of 12 to 20 mm and a width of 4 to 8 mm.

The conductive ink layer (122) may be formed perpendicularly to the direction of sample movement between the absorption pad and the hydrophobic pattern on the porous substrate (100), and serves to form a parallel electric field by contacting the external electrode. If the electric field is applied to one point rather than parallel due to the absence of the conductive ink layer, it may be difficult to simultaneously concentrate multiple samples at a uniform speed.

In one embodiment of the present invention, the conductive ink layer can be formed by coating a conductive ink, such as a silver-containing paste, at a point spaced apart from the hydrophobic pattern at the center by about 1 to 3 mm.

In addition, as illustrated in Fig. 1, the conductive ink layer (122) can be formed on both sides of the porous substrate (100) at intervals of less than 1.5 cm with a central hydrophobic pattern therebetween, and from this, the external electrodes of the (+) and (-) poles can be connected at a short distance, thereby enabling sample concentration even at a low voltage.

The above-mentioned selective ion permeable portion (123) may be formed one or more adjacent to the conductive ink layer, and serves to induce ion concentration polarization (ICP) when voltage is applied through the electrode.

The above ion concentration polarization refers to the phenomenon of electrophoresis (EP), in which ions present in a sample are attracted to an electrode with the opposite electrical properties of each ion and move, due to an external electric field applied to the electrode, and the movement of cations and anions occurs, and only specific ions are transmitted through a selective ion permeable layer, forming a boundary layer of ion depletion and ion enrichment.

In the system of the present invention, when a cation-selective permeable portion (123) such as Nafion is positioned in front of a conductive ink layer (122) that contacts the (+) electrode and the (-) electrode, and a sample containing anions is injected between one or more selective permeable portions and a buffer solution is injected while being supported on an absorption pad, when voltage is applied, anions in the sample move toward the (+) electrode and cations in the buffer solution move toward the (-) electrode through the Nafion layer, so that an ion-depleted region is formed near the (-) electrode and an ion-concentrated region is formed near the (+) electrode, so that anions can be concentrated toward the (+) electrode.

These selective ion permeable portions can be implemented with any material that is selectively ion permeable, and can be formed of a polyelectrolyte such as Nafion, polystyrene sulfonate, or polyallylamine hydrochloride.

When using the system of the present invention as described above, by forming a conductive ink layer perpendicular to the direction of sample movement and applying a parallel electric field, various types of samples, particularly samples containing ionic components that can move due to ion polarization, can be concentrated simultaneously at a constant speed in a short period of time, for example, within 5 minutes.

Accordingly, the present invention provides a method for separating and concentrating a plurality of samples using the above system, the method may include the following steps:

(S1) a step of injecting a sample into each of the plurality of sample movement passages formed in the hydrophilic region of the system;

(S2) a step of injecting a buffer solution into the absorption pad of the above system; and

(S3) A step of applying voltage by contacting an external electrode to the conductive ink layer of the above system to separate and concentrate the injected sample.

In the above step (S1), each of the plurality of samples can be injected in an amount of 0.01 to 2 μL.

The voltage in the above step (S2) may be applied to each of the plurality of sample separation devices under conditions of 10 to 100 V, for example, 50 V, for 1 to 5 minutes, for example.

The concentrated component in the above step (S3) can be analyzed using a conventional analysis method, such as HS-GC/MS, LC/MS, etc.

Hereinafter, in order to help understand the present invention, examples will be given and described in detail. However, the examples according to the present invention may be modified in various different forms, and the scope of the present invention should not be construed as being limited to the following examples. The examples of the present invention are provided to more completely explain the present invention to a person having average knowledge in the art.

Examples:

As illustrated in Fig. 1, a system (1) was prepared, including a porous paper substrate (100), a hydrophobic region (110) formed on the substrate and a hydrophilic region (120) provided with three sample movement passages thereby, cellulose absorption pads (121) and conductive ink layers (122) provided on both sides in the direction of movement of the sample in the hydrophilic region, and a Nafion selective ion permeable portion (123) formed in each of the sample movement passages. Specifically, the size of the substrate was 26 mm × 38 mm, the hydrophobic region occupied about 60% of the total area of the substrate, and the two absorption pads occupied about 20% of the total area of the substrate, and the conductive ink layer was formed by coating an Ag-containing paste at a point spaced apart from the hydrophobic pattern at the center by about 1.5 mm.

A 10 mM phosphate-buffered saline was absorbed into the absorption pad (121) of the above system, and a fluorescent sample containing an anion component (PTS ^4- ) of the following structure dissolved in water was injected between the selective ion permeation portions (123) in each sample passage, and a voltage was applied to separate and concentrate the organic acid in the sample (the applied conditions are shown in Table 1 below).

Sample injection conditions Voltage application conditions density Injection amount Voltage (V) Time(s) Sample (PTS ^4- ) 50mg/ml 0.4㎕ 50 164 PBS buffer 10mM 0.2ml

Comparative example:

Separation and concentration of three types of samples were performed using the same process as Example 1, except that a system in which a conductive ink layer (122) was not formed in Fig. 1 was used.

Figures 2a and 2b show comparisons of voltage application and simultaneous concentration results for multiple samples according to the above examples and comparative examples, respectively.

As can be seen in Fig. 2a, in the embodiment, a parallel voltage was formed by applying a voltage by introducing a conductive ink layer, and an electric field was uniformly formed at multiple points, whereas in the comparative example, an electric field was formed at one point and dispersed due to the absence of a conductive ink layer. As a result, in the embodiment, three types of samples were simultaneously concentrated at a constant speed through the parallel electric field (concentration time <3 minutes), whereas in the comparative example, it was confirmed that the electric field had different distances from each sample movement path, so the samples were not concentrated at a constant speed (Fig. 2b).

In this way, the results of concentrating three types of samples at a constant rate according to the example are additionally presented in Table 2 and Figure 3 below.

As can be seen in Table 2 above, immediately after the injection of the three types of samples, the variation in the concentration intensity was high due to the dispersion phenomenon, but as the concentration process progressed, the relative standard deviation (RSD) value of the concentration intensity between samples decreased (12.3% → 7.0%).

In addition, it can be confirmed from Figure 3 that the peak intensity of all three types of multiple samples increased consistently after concentration.

Claims (12)

A porous substrate; a hydrophobic region in which a hydrophobic material is coated in a pattern shape on one surface of the porous substrate; and a hydrophilic region provided with a plurality of sample movement passages separated by the hydrophobic pattern;
The above hydrophilic region is a system for separating and concentrating multiple samples, comprising an absorbent pad attached to both sides in the direction of movement of the sample, a conductive ink layer formed perpendicular to the direction of movement of the sample between the absorbent pad and the hydrophobic pattern, and at least one selective ion permeable portion formed adjacent to the conductive ink layer,
The conductive ink layer includes a silver-containing paste coating and forms a parallel electric field by contacting an external electrode,
A multi-sample separation and concentration system, wherein the hydrophilic region comprises three or more sample movement channels. delete delete In the first paragraph,
A system for separating and concentrating a sample, wherein the conductive ink layer is formed at a distance of 1 to 3 mm from the hydrophobic pattern. In the first paragraph,
A system for separating and concentrating a sample, wherein the porous substrate is made of a hydrophilic material including paper, cellulose or a mixture thereof. In the first paragraph,
A system for separating and concentrating a sample, wherein the porous substrate has a length of 30 to 45 mm and a width of 20 to 30 mm. In the first paragraph,
A system for separating and concentrating a sample, wherein the hydrophobic region occupies 30 to 70% of the total surface area of the porous substrate. delete In the first paragraph,
A system for separating and concentrating a sample, wherein the above absorbent pad is attached in a size occupying 5 to 20% of the total area of the porous substrate. In the first paragraph,
A system for separating and concentrating a sample, wherein the above absorbent pad is made of cellulose fibers, gelatin fibers, starch fibers or a mixture of two or more thereof. In the first paragraph,
A system for separating and concentrating a sample, wherein the selective ion permeable portion is formed of nafion, polystyrene sulfonate, polyallylamine hydrochloride or a mixture thereof. A method for separating and concentrating multiple samples using a system according to Article 1,
(S1) a step of injecting a sample into each of the plurality of sample movement passages formed in the hydrophilic region of the system;
(S2) a step of injecting a buffer solution into the absorption pad of the above system; and
(S3) A method including a step of applying voltage by contacting an external electrode to a conductive ink layer of the system to perform separation and concentration of an injected sample.