JP2610459B2 - Dry preservation method of polyacrylamide plate as molecular sieve material or sample distribution support - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for drying and storing a gel-like polyacrylamide plate as a molecular sieve material for electrophoresis or a sample distribution support after electrophoresis.

2. Description of the Related Art Polyacrylamide gel is most often used as a molecular sieve material for separating and analyzing biological substances and chemical substances, especially as a support for the distribution of sample components by electrophoresis, in the fields of biology, chemistry and medicine. I have.

Problems to be Solved by the Invention It is desired that a polyacrylamide gel as a material in a two-dimensional electrophoresis method is usually a plate having a thickness of about 1 to 2 mm and an area of about 10 several cm square. In this case, since preparing such a plate-like gel for each analysis requires a great deal of labor and time, it is convenient to use a gel prepared in advance, but a commercially available gel has a large thickness. 1 mm or less. That is, even if a large amount of a plate-like gel having a thickness of 1 mm or more was to be formed in advance, there was no appropriate method for storing the gel in a usable state, and as a result, each time electrophoresis was performed, the above-mentioned troublesome procedure was required. Preparation work was required.

On the other hand, the flat gel after electrophoresis is used for staining and measuring the sample distributed in this plane, but is usually provided with a decompression chamber, a heater, a temperature control circuit, a timer, etc. for storage. Dried by a gel dryer. That is, the flat gel is formed by attaching a filter paper or the like to the lower surface in a decompression chamber of a gel dryer connected to a vacuum pump and heating and drying under reduced pressure. However, this method has the following disadvantages.

(1) The gel shrinks during drying, especially the thickness of the gel plate is about 3m
If the thickness is more than m, the gel will be broken due to the attached filter paper, so that the gel thickness will be limited to about 1 or 2 mm.

(2) Since the gel is attached to a support such as filter paper and dried while pressing, the gel cannot be restored to the original gel plate shape after drying once, while remaining attached to the filter paper.

(3) Even when the gel plate is dried while maintaining a substantially flat shape, it is often bent round during storage, which is inconvenient.

(4) Not only a vacuum pump but also a relatively expensive gel dryer having a heater, a temperature control circuit and a timer must be used.

The present invention solves the above-mentioned drawbacks in storage of a polyacrylamide plate as a molecular sieve material for electrophoresis or a sample distribution support after electrophoresis, and easily drys and stores a polyacrylamide gel plate in a simple method. It is intended to provide a drying and preserving method which can restore the original shape easily.

Means and Actions for Solving the Problems In order to achieve the above object, the present invention relates to a method for preparing a molecular sieve material for electrophoresis or a gel-like polyacrylamide plate as a sample distribution support after electrophoresis, mainly using an organic solvent. The polyacrylamide plate is immersed in a liquid as a component to elute water in the gel, then the polyacrylamide plate is taken out of the liquid, and under reduced pressure, without substantially impairing the air permeability of the entire surface,
It is characterized by drying and curing while maintaining the flat shape.

In the method of the present invention, utilizing the fact that polyacrylamide is inherently plastic, the polyacrylamide gel plate is converted into plastic by immersing it in a solution containing a certain organic solvent to elute water in the gel. ,
After maintaining the flat shape to a size substantially close to the final shrinkage size and shrinking, the flat shape is maintained without further impairing the air permeability of the surface, and vacuum drying is performed at room temperature. The area shrinks to about 1/2 and the volume to about 1/3, and a completely cured flat plate-like storage gel plate is formed.

Description of the Examples In FIG. 1, the gel-like polyacrylamide plate (1) as a material for two-dimensional electrophoresis or a sample distribution support after electrophoresis is made of an organic solvent, preferably ethanol, or this organic solvent and water. Is immersed in a vat (3) containing a solution (2) comprising a mixed solution of In this case, the Saran net (4) arranged on the bottom of the vat (3) so that the entire surface of the polyacrylamide flat plate (1) is almost evenly in contact with the solution (2) while maintaining its flat shape.
Supported on top. In this state, the polyacrylamide gel releases its water into the mixed solution, shrinks while receiving some organic solvent, and changes from a gel state to a plastic state.

After the semi-plastic polyacrylamide flat plate formed as described above is removed from the vat (3), it is placed in a reduced-pressure desiccator as shown in FIG. 2, and the inside of the desiccator is vacuum-suctioned and dried under reduced pressure. In the desiccator (5), the polyacrylamide flat plate (1) has a breathable tissue-like sheet (6) such as a Kimwipe on both sides.
Further, an appropriate protective plate (7) such as a corrugated cardboard is also applied to the outer surface of the tissue-like sheet (6) having the same air permeability, and these sandwich structures are gently maintained by clips or rubber bands. When the inside of the desiccator (5) is depressurized and dried in this manner, the polyacrylamide plate is in a gel-like brittle and unwieldy state. Different hard plastics,
It can withstand rough handling by hand unless it gets wet, and can be stored for a long time.

Specific Example 1 In this example, a surface area of 160 × 140 mm ² and a thickness of 1 mm
18% polyacrylamide gel plates.
This polyacrylamide gel is immersed in 250 ml of a mixture of ethanol 8 and water 3 for 3 to 5 hours. At first, the gel plate which was transparent has an opaque white color, gradually shrinks and becomes a rubbery state, and the gel has no brittleness peculiar to the gel, and becomes extremely easy to handle. This is sandwiched between the cardboard and Kimwipe described above, placed in a vacuum desiccator, sucked in for about 5 hours by a 200 W oil rotary vacuum pump, decompressed, and dried to become a hard plastic. , Is saved.

Specific Embodiment 2 In this embodiment, the thickness is 3 mm, as in the first embodiment.
This was applied to a polyacrylamide gel plate described above. In this case, the thickness becomes three times as large as that of the above-mentioned embodiment, and when it is applied to the above-mentioned mixed solution of ethanol 8: water 2, the shrinkage ratio is relatively too large and cracks are generated. As one step, it is immersed in 750 ml of a mixture of ethanol 4: water for 10 hours. The gel plate shrinks by this immersion, but still maintains a transparent gel state. After this immersion, when the gel plate was transferred into 750 ml of the 8: 2 mixture, the gel plate soon began to exhibit an opaque white color and further contracted. After the immersion is performed for about 5 hours, drying is performed under reduced pressure using a desiccator in the same manner as in Example 1.

The concentration of the organic solvent and the immersion step used in the present invention are not limited to the above examples, and can be appropriately determined according to the gel concentration and the thickness.

In each of the embodiments, ethanol is used as the organic solvent, but various organic solvents such as methanol, other alcohols, and acetone can be used.

Effect of the Invention In the method described above, the dried polyacrylamide plate can be returned to the original gel-like plate again simply by immersing it in water. This was not realized by the conventional gel dryer method, and such reversibility between gel and plastic was repeatedly confirmed.
Therefore, after a gel plate is formed as a material, it is dried and stored. First, it is immersed in water for electrophoresis to return to a gel state, and after electrophoresis and analysis, it is again dried and stored. Then, operations such as immersion in water again and returning to the gel plate can be performed for examination.

As described above, since each side of the gel-like flat plate is dried at the same shrinkage ratio, the gel-like flat plate has very little distortion and can be stored on an accurate scale. In the examples, typically the gel plate shrinks evenly to 70% on one side, 49% in area, and 34% in volume by conversion to a plastic plate, and its background becomes white, Coupled with the similar shrinkage from the gel plate, the stained spot of the sample component becomes extremely easy to see, which is effective for detecting a trace component.

The present invention is also configured as a method for preserving a gel plate in an electrophoresis method, and the dried polyacrylamide plate prepared by this method withstands mechanical external force as a hard plastic, and is very easy to handle. In addition, in view of characteristics such as easy return to the original gel state, the use thereof can be further expanded as follows.

First, it can be used in place of agar as a solid medium for microorganisms such as bacteria and mold. In this case, if a gel promoter that is harmful to the growth of bacteria and the like is washed and removed, the dried plastic is formed, and the resultant is dipped in a desired culture solution to form a gel, whereby bacteria and the like can be inoculated thereon. Then, when it is desired to preserve the state in which bacteria and the like have proliferated and formed a colony, it may be dried again and made into plastic, whereby the colony can be marked clearly.

By converting a gel piece containing a sample into a dry plastic, the sample can be used as a method for surely storing and preserving the sample. In this case, since the thickness of the gel plate is not limited, if the thickness is about 5 mm, which has not been possible in the past, it is very easy to take out the substance after separation.

[Brief description of the drawings]

FIG. 1 is a schematic view showing a stage of immersing a polyacrylamide plate in an organic solvent in the method of the present invention, and FIG. 2 is a cross-sectional view showing a state in which the polyacrylamide plate after immersion in the organic solvent is vacuum-dried. (1) Polyacrylamide flat plate (2) Dipping solution (3) Bat (4) Saran net (5) Desiccator (6) Kimwipe (7) Protection plate (8) ...... Support

Claims (1)

(57) [Claims] A gel polyacrylamide plate as a molecular sieve material for electrophoresis or a sample distribution support after electrophoresis is immersed in a liquid containing an organic solvent as a main component to elute water in the gel, Next, the polyacrylamide flat plate is taken out of the liquid, and dried and cured while maintaining the flat shape without substantially impairing the air permeability of the entire surface under reduced pressure.