Hydroxypropyl-sulfobutyl-&bgr;-
cyclodextrin, the preparation method, analytical method, and the pharmaceutical application thereof. The hydroxypropyl-sulfobutyl-&bgr;-
cyclodextrin is a derivate of
cyclodextrin which is substituted by hydroxypropyl group and sulfobutyl group: n-(2,3,6-O-2-hydroxypropyl)-m-(2,3,6-O-sulfobutyl)-&bgr;-cyclodextrin. The number of
substituent groups per mole cyclodextrin is n hydroxypropyl groups and m sulfobutyl groups. “n” represents the average
substituent degree of hydroxypropyl groups; “m” represents the average
substituent degree of sulfobutyl groups; “n+m=z” is the gross average substituent degree, in which n is a random integer chosen from 1, 2, 3, 4, 5, 6, 7, 8, 9; m is a random integer chosen from 1, 2, 3, 4, 5, 6, 7, 8, 9; and the gross average substituent degree z is a random integer chosen from 2, 3, 4, 5, 6, 7, 8, 9, 10. The present invention shows low
haemolysis and
low toxicity.