CN112206844A

CN112206844A - Device and method for filtering small-volume biological sample solution

Info

Publication number: CN112206844A
Application number: CN202010828230.2A
Authority: CN
Inventors: 刘程; 张永明; 唐堂
Original assignee: Wuhan Mai Tver Biological Technology Co ltd
Current assignee: Wuhan Mai Tver Biological Technology Co ltd
Priority date: 2020-08-17
Filing date: 2020-08-17
Publication date: 2021-01-12

Abstract

The invention provides a device and a method for filtering a small-volume biological sample solution, wherein the device for filtering the small-volume biological sample solution comprises the following components: the device comprises a syringe, a filter connected to the syringe and a liquid transfer suction head connected with the filter. Compared with the prior art, the invention has the beneficial effects that: (1) the device is simple, easy to obtain and easy to splice; (2) the liquid-transfering suction head plays a role in drainage, and can collect the filtered sample solution in the liquid-transfering suction head, thereby reducing the loss of samples, filtering small-volume samples and simultaneously reducing the pollution to the samples.

Description

Device and method for filtering small-volume biological sample solution

Technical Field

The invention belongs to the field of analytical chemistry, and particularly relates to a device and a method for filtering a small-volume biological sample solution.

Background

In laboratories for trace compound analysis, pretreated biological samples are usually concentrated, but the sample solution must be filtered in order to avoid clogging the instrument during sample introduction.

At present, a syringe is used more frequently and is connected with a filter but not connected with a needle, because the concentrated sample solution is turbid, the filtration resistance is higher, and bubbles often appear, so that the irreversible loss of the sample is caused, the volume of the concentrated sample solution is usually only 100 plus 200 mu L, and meanwhile, the solution loss is caused due to the incapability of draining during collection, so that the difficulty of pretreatment is greatly increased.

Disclosure of Invention

In order to overcome the defect that the solution is lost during filtering in the prior art, the invention provides a device and a method for filtering a small-volume biological sample solution.

The specific technical scheme is as follows:

an apparatus for filtering a small volume of biological sample solution, except that the apparatus for filtering a small volume of biological sample solution comprises: the device comprises a syringe, a filter connected to the syringe and a liquid transfer suction head connected with the filter.

Further, the filter is connected with the pipetting tip through a thread structure.

The method for filtering a small volume of biological sample solution using the above apparatus is different in that the method for filtering a small volume of biological sample solution comprises the steps of:

step S1: measuring a solution and adding the solution into the injector;

step S2: pressing the piston of the syringe to filter the solution through the filter;

step S3: removing the pipette tip and bringing the pipette tip into close proximity with the inner wall of the container of collection solution to cause the solution to flow into the container.

Further, in step S1, after the devices are spliced, the solution is added to the syringe.

Further, in step S3, if the solution in the pipette tip remains, the upper end of the pipette tip is squeezed.

Further, in step S1, the solution is measured by a pipette and then fed to the bottom of the syringe.

Compared with the prior art, the invention has the beneficial effects that: (1) the device is simple, easy to obtain and easy to splice; (2) the liquid-transfering suction head has played the effect of drainage, can let the sample solution gathering after filtering in liquid-transfering suction head, simultaneously, because the filtration resistance reduces, the convenient drainage in later stage has reduced the loss of sample, can filter little volume sample.

Drawings

FIG. 1 is a view showing the construction of the apparatus;

FIG. 2 is a diagram of the collection process after filtration of the solution using the present apparatus;

in the drawings, the components represented by the respective reference numerals are listed below:

1-syringe, 2-filter, 3-liquid transfer suction head and 4-collection container.

Detailed Description

The principles and features of this invention are described below in conjunction with the following drawings, which are set forth by way of illustration only and are not intended to limit the scope of the invention.

Example 1

A device for filtering a small volume of a biological sample solution, comprising: the device comprises a syringe, a filter connected to the syringe and a liquid transfer suction head connected with the filter.

In this embodiment, the syringe, filter and pipette tip may be assembled as shown in FIG. 1 using commercially available products.

Also can design the customization simultaneously, adopt helicitic texture to connect filter and liquid-transfering suction head.

Example 2

A method of filtering a small volume of biological sample solution using the apparatus of example 1 comprising the steps of:

step S1: after the injector, the filter and the liquid transfer suction head are spliced, the liquid transfer gun is used for measuring the solution and adding the solution into the bottom of the injector, so that the solution can be prevented from being attached to the inside of the injector to cause loss;

Example 3

step S1: splicing the injector, the filter and the liquid transfer suction head, measuring a solution by using a liquid transfer gun, and adding the solution to the bottom of the injector;

step S3: and taking down the liquid transfer suction head, enabling the liquid transfer suction head to be tightly attached to the inner wall of the solution collecting container, and squeezing the upper end of the liquid transfer suction head after a period of time to enable air to push the solution to flow into the container.

Example 4

1mL of the fresh plant-derived extract was concentrated to dryness, and then reconstituted with 100. mu.L of 80% methanol, and the resulting reconstituted solution was centrifuged to obtain a supernatant, which was then filtered by the method of example 3 using a 0.22 μm PTFE filter, and the results of the parallel experiments are shown in Table 1.

Table 1 example 3 filtration process loss rate results

	1-1	1-2	1-3
				Volume before filtration (μ L)	100	100	100
Volume after filtration (μ L)	70.3	68.5	72.6
				Loss ratio (%)	29.7％	31.5％	27.4％

Comparative example 1

The pipette tip of the apparatus of example 1 was removed, and filtration was carried out by the method of example 3.

1mL of an extractant of a fresh-sample plant (the same as in example 4) was concentrated to dryness, and then reconstituted with 100. mu.L of 80% methanol, and the resulting reconstituted solution was centrifuged to obtain a supernatant, which was then filtered through a 0.22 μm PTFE membrane, and the results of the experiments were repeated as shown in Table 2.

Table 2 example 3 filtration process loss rate results

	2-1	2-2	2-3
				Volume before filtration (μ L)	100	100	100
Volume after filtration (μ L)	5.6	15.4	11.9
				Loss ratio (%)	94.4％	84.6％	88.1％

In the filtering process, under the action of pressure, the solution generates a large amount of bubbles due to large resistance and flows out quickly, and the diameter of the lining pipe is small, so most of the solution is lost, and the loss rate is high.

In tables 1 and 2, since the volume of the solution is not easily measured, it is necessary to measure the weight m of the solution before filtration, divide the weight m by the volume V (known) of the solution to obtain the density ρ of the solution, and then obtain the mass m of the solution after filtration by the difference method₁Then m according to the formula₁The solution V after filtration is obtained by rho calculation₁。

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.

Claims

1. An apparatus for filtering a small volume of biological sample solution, the apparatus comprising: the device comprises a syringe, a filter connected to the syringe and a liquid transfer suction head connected with the filter.

2. The apparatus of claim 1, wherein the filter is connected to the pipette tip by a threaded structure.

3. A method of filtering a small volume of biological sample solution using the device of claim 1, wherein the method of filtering a small volume of biological sample solution comprises the steps of:

step S1: measuring a solution and adding the solution into the injector;

4. The method for filtering a small volume of biological sample solution of claim 3, wherein in step S1, the solution is added to the syringe after the device is assembled.

5. The method for filtering a small volume of biological sample solution of claim 3, wherein in step S3, if there is a residue of solution in the pipette tip, the upper end of the pipette tip is squeezed.

6. The method for filtering a small volume of biological sample solution of claim 3, wherein in step S1, the solution is delivered into the bottom of the syringe after being metered by a pipette.