Impact of optical fiber characteristics in SPR sensors for continuous glucose monitoring

Optical fibers are particularly suited for glucose continuous monitoring in patients with diabetes thanks to the possibility of realizing high sensitivity transducers, joined with fiber intrinsic properties such as minimal invasiveness and impossibility of electrocution. One of the most effective approaches to develop high performance fiber sensors exploits the surface plasmon resonance (SPR) in a gold layer deposited on the fiber surface. The paper, using a model for the SPR in multimode fibers that has been experimentally validated, analyzes the impact of geometrical (e.g. fiber size) and optical parameters (e.g. numerical aperture) of some optical fibers to be used in the development of such glucose sensors, with the aim of identifying the most cost-effective solution. A body temperature compensation layout to overcome the SPR cross-sensitivity is then studied for the most promising configurations.