Body-mountable devices and methods for embedding a structure in a body-mountable device are described. A body-mountable device includes a transparent polymer and a structure embedded in the transparent polymer. The transparent polymer defines a posterior side and an anterior side of the body-mountable device. The structure has an outer diameter and an inner diameter and includes a sensor configured to detect an analyte and an antenna. The antenna includes a plurality of conductive loops spaced apart from each other between the outer diameter and the inner diameter.
