Alkylated cyclodextrin compositions and processes for preparing and using the same
The present disclosure is related to processes for efficient large-scale preparation of alkylated cyclodextrins. The processes of the present disclosure provide high purity alkylated cyclodextrins with high purity and low levels of chloride while improving efficiency, increasing batch size, and reducing total process time.
1 . A process for preparing an alkylated cyclodextrin composition, the process comprising:
(a) mixing a starting cyclodextrin with an alkylating agent to form a reaction milieu comprising an alkylated cyclodextrin;
(b) conducting a first one or more separations to form a first solution comprising the alkylated cyclodextrin, wherein the one of more separations comprises diafiltration through an ultrafiltration membrane;
(c) treating the first solution with an activated carbon to produce a second alkylated cyclodextrin solution; and
(d) conducting a second one or more separations to form a third alkylated cyclodextrin solution, wherein the one or more separations comprises nanofiltration through a nanofiltration membrane;
wherein the alkylated cyclodextrin is a sulfoalkyl ether cyclodextrin of Formula (II):
wherein p is 4, 5, or 6, and R 1 is independently selected at each occurrence from —OH or —O—(C 2 -C 6 alkylene)-SO 3 − -T, wherein T is independently selected at each occurrence from pharmaceutically acceptable cations, provided that at least one R 1 is —OH and at least one R 1 is O—(C 2 -C 6 alkylene)-SO 3 − -T.
2 . The process of claim 1 , wherein solvent is added to dilute the reaction milieu formed in step (a) prior to conducting the first one or more separations.
3 . The process of claim 2 , wherein the solvent is water.
4 . The process of claim 1 , wherein the concentration of the alkylated cyclodextrin in step (b) is less than 10% (w/w) prior to the first one or more separations.
5 . The process of claim 1 , wherein the concentration of the alkylated cyclodextrin in step (b) is from about 3% (w/w) to about 8% (w/w) prior to the first one or more separations.
6 . The process of claim 1 , wherein the ultrafiltration membrane in step (b) has a molecular weight cut-off (MWCO) of about 1000 Da or lower.
7 . The process of claim 1 , wherein the ultrafiltration membrane in step (b) has a MWCO of about 500 to about 1000 Da.
8 . The process of claim 1 , wherein the activated carbon of step (c) is prepared by a method comprising the step of subjecting the activated carbon to an initial carbon washing process comprising adding a portion of the first solution comprising the alkylated cyclodextrin from step (b) to the carbon, soaking the carbon in the first solution, and eluting and discarding the solution; and, wherein the activated carbon of step (c) is further subjected to a washing process comprising flowing water over the carbon after the initial carbon washing process and eluting the water.
9 . The process of claim 8 , wherein the eluted wash water has a residual conductivity of 10 μS/cm or less; or wherein the activated carbon is phosphate free; or wherein the activated carbon is steam activated; or wherein the activated carbon is granular.
10 . The process of claim 1 , wherein the concentration of the alkylated cyclodextrin in the second alkylated cyclodextrin solution introduced into step (d) is from about 3% (w/w) to about 8% (w/w).
11 . The process of claim 1 , wherein the concentration of the alkylated cyclodextrin in the second alkylated cyclodextrin solution introduced into step (d) is from about 4% (w/w) to about 7% (w/w).
12 . The process of claim 1 , wherein the nanofiltration membrane in step (d) has a MWCO of about 500 Da or lower.
13 . The process of claim 1 , wherein the nanofiltration membrane in step (d) has a MWCO of about 150-500 Da.
14 . The process claim 1 , wherein the nanofiltration of step (d) is conducted for a period of 30 minutes to 12 hours.
15 . The process of claim 1 , wherein the nanofiltration of step (d) is conducted for a period of about 1 hour to about 3 hours.
16 . The process of claim 1 , wherein the concentration of the alkylated cyclodextrin in the third alkylated cyclodextrin solution is from about 10% (w/w) to about 25% (w/w).
17 . The process of claim 1 , further comprising concentrating the third alkylated cyclodextrin solution for a period of about 2 hours to about 24 hours to form a fourth alkylated cyclodextrin solution.
18 . The process of claim 1 , further comprising concentrating the third alkylated cyclodextrin solution for a period of about 9 hours to form a fourth alkylated cyclodextrin solution.
19 . The process of claim 17 , wherein the concentrating the third alkylated cyclodextrin solution is performed by distillation.
20 . The process of claim 17 , wherein the concentration of the fourth alkylated cyclodextrin solution is from about 30% (w/w) to about 70% (w/w).
21 . The process of claim 1 , further comprising removing the solvent from the fourth alkylated cyclodextrin solution to form a solid alkylated cyclodextrin, wherein the solvent is removed by distillation, lyophilization, or spray-drying.
22 . The process of claim 21 , wherein the solid alkylated cyclodextrin comprises less than 500 ppm of a phosphate.
23 . The process of claim 21 , wherein the solid alkylated cyclodextrin comprises less than 0.05% (w/w) of a chloride.
24 . The process of claim 21 , wherein the solid alkylated cyclodextrin comprises less than 0.002% (w/w) of a chloride.
25 . The process of claim 1 , wherein the process comprises preparing a single batch of alkylated cyclodextrin wherein the initial cyclodextrin has a mass greater than 275 kg.
26 . The process of claim 1 , wherein the alkylated cyclodextrin has an average degree of substitution of 2 to 9.
27 . The process of claim 1 , wherein the alkylated cyclodextrin has an average degree of substitution of 6 to 7.5.
28 . The process of claim 1 , wherein R 1 is independently selected at each occurrence from —OH or —O—(C 4 alkylene)-SO 3 − -T, and -T is Na + at each occurrence.
29 . The process of claim 21 , further comprising combining the solid alkylated cyclodextrin with one or more excipients.
30 . The process of claim 21 , further comprising combining the solid alkylated cyclodextrin with an active agent.
31 . A product prepared by the process of claim 1 .