Controlled release of bioactive materials using alginate gel beads

Claim 1

A process for preparing alginate gel beads containing insecticide materials consisting essentially of: (a) mixing an effective quantity of alginate for gelation with an effective quantity of 1-a-cyano-c-phenoxybenzyl d, cis-dibromochrysanthemate, for incorporation into a final gel bead, in water; (b) placing the mixture in a vessel equipped to dispense liquids dropwise; (c) mixing an effective quantity of water-soluble metal salt or acid which can gel alginates, with an effective quantity of water to obtain a solution; (d) adding, dropwise, the alginate mixture of (b) into the solution of (c); thus forming gel beads, which contain the insecticide material dispersed uniformly therein, allowing the beads to remain in contact with the solution of (c) for an effective period of time necessary to allow gelation, and (e) separating the gelled beads from the solution of (c).