Electrically conductive adhesive hydrogels

Abstract

A composition providing electrically conductive adhesive hydrogels suitable for use as skin contact adhesives and, particularly, suitable for use as an electrical interface for disposable medical devices. The hydrogels are cationic acrylates and may be, for example, preferably made from acrylic esters of quaternary chlorides and/or sulfates or acrylic amides of quaternary chlorides. The present hydrogels are formed by free radical polymerization in the presence of water, preferably by ultra-violet curing with initiator and multi-functional cross-linking agent. The present hydrogels also preferably include a buffer system to help prevent discoloration of the hydrogels and/or hydrolysis of the hydrogels and/or improve shelf-life. Other additives may be added to the present hydrogels either before or after curing (i.e. conductivity enhancers, pharmaceuticals, humectants, plasticizers, etc.) depending on intended end-use. The present hydrogels hydrate a subject's skin, readily wet around a subject's skin surface hair (e.g. chest hair), and protect against burning of a subject upon or due to electrical stimulation through the hydrogel. In addition, the present hydrogels are sufficiently cohesive to enable direct hydrogel-to-hydrogel contact and storage (i.e. without a barrier therebetween), yet remain readily separable. Furthermore, the present hydrogels may be presented in a formula which is non-corrosive to aluminum in contact therewith, and pass standards testing for biocompatibility and electrical properties as developed by the Association for the Advancement of Medical Instrumentation (AAMI) and accepted by the American National Standards Institute.