Burroughs Wellcome Co.

Bend Research, Inc.

James W Brooke

Richard W Baker

Kelly L Smith

Walter Christian Babcock

Mark E Tuttle

Matthew F Holmes

A durable and sprayable controlled release bead of active ingredient in the pores of a polymeric micro-porous bead having an anisotropic pore structure of large pores in the interior and small pores at the surface, the gradation of pore sizes between the interior and the surface being continuous.

Asymmetric microporous beads for controlled release

Prills of pharmaceutically acceptable material are coated first with a water-permeable polymeric matrix containing a water-soluble pharmaceutically beneficial agent and then overcoated with a water-permeable film containing dispersed therein a water-soluble, particulate pore-forming material.

Delivery system

A composition for use in an aqueous environment which comprise a formulation containing a water-soluble pharmaceutically beneficial agent, a water-insoluble, water-permeable film coating surrounding the formulation, and particulate, water-soluble, pore-forming material dispersed within the film coating.

Pharmaceutical delivery system

There is disclosed novel copper ion-exchange media and processes for the recovery of cupric ion from ammoniacal copper solutions and for the recovery of spent printed circuit board etchant. The novel ion-exchange media comprise hydrophobic nonporous polymer plasticized and swollen with a monomeric organic liquid copper ion-exchange agent such as beta-diketones or hydroxyoximes. A novel copper ion-complexing agent, 1-n-octylphenyl-p-1,3-butanedione, is also disclosed. The processes essentially comprise contacting the ammoniacal cupric ion-containing solution or spent etchant with the novel copper ion-exchange media to extract copper in cupric ion form. Copper can be recovered therefrom by conventional methods such as acid stripping and electrowinning.

Growing community of inventors

Sisters, OR, United States of America

James W Brooke