a first flexible membrane having a first interlocking elongate segment;

a second flexible membrane having a second interlocking elongate segment and the first and second interlocking elongate segments cooperate to form an elongate undercut mechanical interlock along a peripheral edge between the first flexible membrane and the second flexible membrane with the first interlocking elongate segment and cooperate to provide a cavity between the first membrane and the second membrane configured to receive a glucose sensor and provide resistance to edge peeling about a periphery of the cavity to realize a desired sensitivity for the glucose sensor; and

at least one of the first membrane and the second membrane comprising a semi-permeable portion comprising a diffusion layer configured to regulate diffusion characteristics of glucose through the membrane to realize a sensitivity for a sensor in the cavity; wherein:

the first interlocking segment comprises an elongate ridge and the second interlocking segment comprises a channel having an ensmalled distal width and an enlarged proximal width complementary to the elongate ridge and interlocking in assembly.