Patent ID: 7445766

Claim:
A method of detecting an analyte in vivo comprising: implanting at a site in a patient a device which comprises: one or more discrete reservoirs each containing at least one reacting component, at least one non-degradable barrier layer covering an opening in each of the one or more discrete reservoirs, the non-degradable barrier layer being selectively permeable to an analyte to be detected, wherein the reacting component remains inside the reservoirs, and a degradable barrier layer, which is impermeable to the analyte to be detected and which covers the at least one non-degradable barrier layer over the reservoir opening; disintegrating or permeabilizing the degradable barrier layer over at least one of the reservoirs to permit the analyte at the site to enter the reservoir and react with the at least one reacting component; and using a sensor positioned externally from the reservoir to detect the reaction between the reacting component and the analyte.