JPH02115292A - Method for rendering container for aqueous solution hydrophobic - Google Patents

Abstract

PURPOSE:To obtain a container in which, when a protein or the like is crystallized from an aqueous solution, a crystal of the protein or the like can grow larger in good yields in that part of the solution which is distant from the wall without wetting it by subjecting the inside of the container to a specified treatment. CONSTITUTION:The inside of a container for an aqueous solution is coated with a pressure-sensitive adhesive (e.g., polyvinyl butyrate of a degree of polymerization of 700) and roughened by spraying an insoluble particulate substance (e.g., glass beads of a diameter of 200mum) on it and fixing them. This surface is rendered hydrophobic by coating with a hydrophobic agent (e.g., dichlorodimethylsilane).

Description

[Detailed Description of the Invention] [Summary] Regarding a method for making an aqueous solution container hydrophobic, the purpose is to make the inner surface of the container highly hydrophobic. The method for making an aqueous solution container hydrophobic is made by scattering and fixing a substance to make the inner surface of the container uneven, and then applying a hydrophobizing agent to the uneven inner surface of the container to make it hydrophobic.

[Industrial application field] The present invention relates to a method for hydrophobizing an aqueous solution container.

In recent years, with advances in protein engineering, research has been actively conducted to analyze the structure of proteins and obtain proteins with higher functionality.

X-ray analysis is mainly used to analyze the structure of proteins, but large, high-quality protein crystals are required for highly accurate analysis, and progress in crystallization technology is essential. has become an issue.

Regarding crystallization technology, the static batch method has been used so far.

Growth techniques such as vapor diffusion and free interface diffusion have been developed.

In this case, in order to obtain large, high-quality protein crystals in good yield, it is necessary to grow the crystals in a solution that is far away from the walls of the container used for crystallization, without wetting the walls with an aqueous solution.

[Conventional technology]

As methods for making the inner surface of a container hydrophobic, methods such as surface treatment with a hydrophobizing agent and forming a hydrophobic film on the surface have been used.

That is, a surface treatment agent such as dimethyldichlorosilane is used for the former, and a fluororesin-based or silicone resin-based film forming agent is used for the latter.

However, since the inner surface of the container is flat, the "contact angle" representing the degree of hydrophobicity of the surface is often less than 100°, and therefore sufficient hydrophobicity cannot be obtained.

FIG. 2 is an explanatory diagram of the "contact angle" θ, and when the container surface 1 exhibits sufficient hydrophobicity, the water droplet 2 becomes spherical and the contact angle θ
exceeds 100°. (A in the same figure) However, if the hydrophobicity is insufficient, the contact angle θ shows an acute angle of 90° or less. (B in the same figure) The problem we are trying to solve] As mentioned earlier, without wetting the walls of the container with an aqueous solution,
In order to grow crystals in the solution away from the wall, it is necessary to maintain the contact angle θ of the aqueous solution at 100° or more, as shown in FIG. 2(A).

However, in hydrophobic treatment using conventional surface treatment agents, the contact angle is generally 100° or less, and there is a problem in that sufficient hydrophobicity is not obtained.

[Means to solve the problem]

The above problem was solved by applying an adhesive to the inner surface of a container containing an aqueous solution, then scattering insoluble particulate matter to make the inner surface of the container uneven, and then applying a hydrophobizing agent to the uneven inner surface of the container. This can be solved by coating it to make it hydrophobic.

[Effect]

The present invention roughens the inner surface of the container using the enzyme theory and makes this surface hydrophobic with a hydrophobic agent, thereby giving the surface more hydrophobicity than simply treated with a hydrophobic agent. be.

That is, Wenzel's equation is expressed by the following equation.

cos θ'/cos θ=A/A'>1.5 -1l
Where, A is the true surface area, A' is the apparent surface area, θ is the true contact angle, and θ' is the apparent contact angle. From this formula, it can be seen that for surfaces with a true contact angle of 90° or more, the apparent contact The angle is shown to be larger.

That is, according to (1) 2, when there are irregularities on the surface, if the surface essentially exhibits hydrophobicity, it becomes more hydrophobic, and conversely, if it shows hydrophilicity, it becomes more hydrophilic. be able to.

FIG. 1 shows a method according to the present invention for increasing hydrophobicity using Wenzel's theory.

First, the container surface 1 is washed to make it clean.

(A in the same figure) Next, the adhesive 3 is applied onto the container surface 1 by a method such as dissolving it in a suitable solvent.

(See Figure B) Next, water-insoluble particulate matter 4 is sprinkled onto the adhesive 3 and fixed to the surface, thereby forming irregularities on the surface.

(C in the same figure) Next, after the adhesive 3 has solidified, the hydrophobic agent 5 is applied thereon and assimilated, thereby making it possible to make the surface of the container surface 1 uneven.

〔Example〕

After performing ultrasonic cleaning on the inner surface of the glass container using a detergent and thoroughly drying it, wash it with 5% ethanol by weight of polyvinyl phyllate with a degree of polymerization of 700. A liquid was added and the excess was drained to form an adhesive layer with a thickness of about 100 μm on the inner surface.

Then, before the adhesive layer was dried, glass beads having a diameter of 200 μm as an insoluble particulate material were placed in a container, and the excess was discharged to form an uneven layer.

Next, a 2% chloroform solution of dichlorodimethylsilane as a hydrophobizing agent was put into the container, and after draining the excess, it was washed with water and dried.

By carrying out the above treatment, the contact angle of water increased from 95° to 120° when a smooth surface was subjected to hydrophobizing treatment, thereby achieving a large hydrophobizing effect.

〔Effect of the invention〕

By implementing the present invention, it was possible to roughen the inner surface of a container used for protein crystallization, such as a glass container or a plastic container, thereby making the inner surface of the container highly hydrophobic.

Note that this hydrophobicization method is not limited to protein crystallization, but can be used for crystallization of any material.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing a method of implementing the present invention, and FIG. 2 is a sectional view illustrating the contact angle θ. In the figure, ■ is the container surface, 2 is the water droplet,

Claims (1)

[Claims] After applying an adhesive to the inner surface of a container containing an aqueous solution, the inner surface of the container is made uneven by scattering and fixing insoluble particulate matter, and then a hydrophobizing agent is applied to the uneven inner surface of the container. A method for making an aqueous solution container hydrophobic, the method comprising making an aqueous solution container hydrophobic.