PREPARATION METHOD OF UNIFORM CRYSTAL OF INSULIN

摘要

PURPOSE: A method of preparing crystals of insulin of substantially uniform particle size and shape is provided which can produce uniform hyperfine crystals in a very short time(several seconds to 2 min) in high yield. CONSTITUTION: Crystals of insulin having a particle size of below 10 micrometer are manufactured by (c)adjusting the pH of an acidic insulin solution from a pH below the isoelectric point of insulin to about pH 9.0 to about pH 10.5 with a base, (c)forming in itself fine particles being capable of acting as a seed in the insulin solution, reducing the solubility of insulin in the insulin solution, and (d)crystallizing the insulin. The reduction of the solubility of the insulin in the insulin solution is done by adding an acid such as hydrochloric acid to the insulin solution. The crystals of the insulin of substantially uniform particle size and shape, which have a particle size of below 10 micrometer, can be produced in a yield of above 99% in several seconds to 2 min.