JPH0367536B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a bead-shaped agar gel having excellent separation ability for use in gel chromatography.

Gel chromatography is widely used in the field of measuring the molecular weight and molecular weight distribution of synthetic polymers such as proteins and polysaccharides. be.

Fillers from crosslinked dextrins and crosslinked polyacrylamides are conventionally used as fillers suitable for aqueous solvents.

It is known that an aqueous agar solution forms a gel at low temperatures and becomes a floating sol at high temperatures, and can be used as a packing material for gel chromatography. It is also known that it is suspended in granular form, gelled and separated when cooled.

However, with this method, it is not possible to obtain agar beads with effective molecular sieve function, and because the shape is unstable, it is difficult to obtain beads with sufficient separation ability as a packing material for gel chromatography. At present, it is only described in the published literature and has not been put into practical use.

The object of the present invention is to obtain agar beads having sufficient separation ability as a gel chromatography packing material and having a uniform shape.

Commercially available agar or agar powder is used as the agar, and a mixed organic solvent of an aromatic solvent such as toluene and a polar organic solvent such as chloroform is used as the organic solvent.
Agar beads are obtained by using a nonionic water-soluble surfactant such as a polyethylene glycol condensate and gradually injecting the mixture into an organic solvent mixture containing the surfactant while stirring vigorously to cause gelation and precipitation. . Then, by sieving these agar beads through a mesh-sized nylon mesh, agar beads with a uniform particle shape are obtained, thereby solving the drawbacks of the conventional manufacturing method and obtaining agar beads suitable for the above purpose. was completed. When looking at the shape of these agar beads under a microscope, they appear to be clusters of spherical or oval shapes resembling peeled grape berries.

Next, to explain the present invention in more detail with reference to an example, 4 g of commercially available agar powder was suspended in 100 ml of distilled water and dissolved by boiling to prepare a 4% agar solution ().

Apart from this, 460ml of toluene and 140ml of chloroform
ml of an organic solvent mixture, add and dissolve 3.5 g of a surfactant mixture containing Tween 85 (trade name: Tween 80) as a nonionic surfactant at a ratio of 2:3 to make an organic solvent solution ( )
Create.

This solution () is poured into the round-bottomed separable flask in Step 3, and the 4% agar solution () is gradually added thereto while stirring vigorously with a magnetic stirrer while keeping the temperature at about 40°C. After the addition, tap water from Step 1 is added while continuing to stir to rapidly lower the temperature of the reaction system. Thereafter, the agar solution is gelled by continuing stirring for an additional 2 to 3 minutes. At this point, stirring is stopped and the organic solvent layer and aqueous layer are separated. The gelled agar beads settle toward the water layer, completing the granulation of the agar. The granulated agar thus produced is collected with a nylon mesh of about 140 μm, the organic solvent is roughly removed, and then thoroughly washed with tap water.

Since the agar beads obtained in this way still contain organic solvent on their surface and inside, they were filtered and washed with ethanol using a glass filter, heated to a temperature 5 to 6°C higher than room temperature, and heated under reduced pressure. Vacuum using an evaporator to completely remove the trace amount of organic solvent remaining.

Next, the agar beads were further thoroughly washed with distilled water, suspended in 1N hydrochloric acid, heated at 30°C for 30 minutes, and washed again with distilled water to obtain agar beads with excellent separation ability. .

The agar beads obtained in this way include beads of various diameters, so when they are sieved through a nylon mesh of an appropriate mesh size, they are separated into agar beads of uniform particle size and used for different purposes. can.

The agar beads formed by the method of the present invention have a stable shape, so they exhibit an effective molecular sieve function, and since the particle size can be separated, they can be used appropriately depending on the purpose, making them extremely effective. It exhibits unique characteristics.

Claims (1)

[Claims] 1. Add distilled water to agar powder and dissolve by boiling to obtain an agar solution (2). Separately, add a mixed organic solvent of toluene and chloroform and a nonionic surfactant to obtain a mixed organic solvent solution (2). 1. A method for producing agar beads having a molecular sieve function, which comprises gradually injecting the agar solution () while vigorously stirring the liquid () to obtain granular gelled agar beads.