Abstract: A substance transfer device for topical or transdermal drug delivery to a living body or collection of fluids from a living body, comprises a layer of skin or wound surface compatible adhesive having a surface for contacting the body, and channels therethrough which provide liquid communication with depots of drug or collection means. These channels form discrete, exposed areas of drug composition or drug delivery means, surrounded by the adhesive. The drug contained in the device does not need to pass through the layer of adhesive before contacting the underlying skin. In one arrangement, particularly suitable for delivery of macromolecular drugs, the channels extend through the entire thickness of the adhesive layer, and communicate with reservoirs of drug.

Abstract: There is provided a flocculating process, especially for clay-water suspensions, in which high molecular weight polymers of N-loweralkyl substituted acrylamides and methacrylamides are used as flocculating agent. There are also provided novel polymeric flocculating agents which have the property of exhibiting a critical flocculation temperature, below which they will cause flocculation of suspended solids but above which they are ineffective as flocculants.