| 摘要 |
Gel particles or beads can be prepared by forming a hot aqueous solution of a gelling agent, and discharging the hot gelling agent solution through a discharge orifice into a cold moving stream of hydrophobic liquid so that the gelling agent solution cools rapidly and good quality gel particles coalesce in the cold hydrophobic liquid stream. The cold hydrophobic liquid stream can be contained in a conduit so that the cold hydrophobic liquid stream moves past the discharge orifice and exerts a force on hot solution in the discharge orifice, the force acting to withdraw the hot solution from the discharge orifice. Optionally, the gel particles can be crushable gel beads 10 formed of an agar complex providing cosmetic, pharmaceutical, etc. delivery vehicles for topical delivery of biologically or cosmetically active agents. Preferred agar beads 10 are complexes of a continuous phase of agar gel 12 in a self-supporting solid or semi-solid form with a restraining polymer 14. Various active agents 16 may be bound to restraining polymer 14, for, example ascorbic acid, lactic acid or papain.
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