PROLONGATION OF ACTIVITY RETENTION

摘要

PURPOSE:A vessel made of permeable membrane is filled with a clathrate complex consisting of an active substance and a cyclodextrin polymer of such a molecular weight as it cannot pass through the membrane and sealed tightly to keep a constant activity for a long period of time. CONSTITUTION:A vessel at least partially made of a permeable membrane is filled with a clathrate complex consisting of an active substance and a cyclodextrin polymer of such a high molecular weight as it cannot pass through the membrane and sealed tightly. The permeable membrane is made of cellulose or acetylcellulose preferably. An example of the active substance is a drug, agricultural chemical or flavor and the amount is generally 0.05-0.20pts.wt. per 1pt. of the cyclodextrin polymer. Since said polymer does not diffuse toward the outside of the vessel, the dissociation into the active substance and the cyclodextrin polymer is slow and a constant level of activity is kept for a long period of time.