Preparation of polysaccharide beads
View Patent ↗The present invention relates a method of preparing agarose beads, which method results in a population of beads which are of relatively uniform particle size. In an advantageous embodiment, the beads are of a particle size less than 10 μm, and the coefficient of variation C.V. of the population is less than 15%. The beads according to the invention are advantageously used in biological separation methods, such as in the production of chromatographic packing materials; drug carriers; or in any method of biological engineering.
1. A method of preparing agarose gel beads, which method comprises the following steps:
(a) providing an agarose aqueous phase W comprising agarose;
(b) providing a water-immiscible oil phase O, in which at least one emulsifier is dissolved;
(c) mixing the water phase W and oil phase O to obtain a W/O emulsion;
(d) passing the emulsion through a hydrophobic microporous membrane by applying pressure to obtain a W/O emulsion with substantially uniform droplet size; and
(e) reducing the temperature of the W/O emulsion droplets until agarose gel beads are formed.
2. The method of claim 1 , wherein the pressure is 0.5-3.0 kgf/cm 2 in step (d).
3. The method of claim 1 , wherein the emulsion flow rate through the microporous membrane is between 0.5 and 1.5 m 3 m −2 h −1 in step (d).
4. The method of claim 1 , wherein the pore diameter of the microporous membrane is between 2 and 20 μm.
5. The method of claim 1 , wherein the agarose concentration in step (a) is between 0.1 wt % and 20.0 wt %.
6. The method of claim 1 , wherein steps (a), (c) and (d) are conducted under heating.
7. The method of claim 1 , wherein step (d) results in agarose gel beads having a substantially uniform particle size.
8. The method of claim 1 , which includes a step of adding functionalities to the agarose gel beads obtained from step (e).
9. The method of claim 8 , wherein the functionalities are charged groups.