A photonic sensor system includes: a photodetector; a signal processor coupled to the photodetector; and a sensor structure configured to provide fluid-response selectivity, spatially distribute light, and to receive light from a light source and convey light to the photodetector. The sensor structure includes a plurality of fluid sensitive interferometric nanostructure layers manufactured on a substrate; wherein the plurality of fluid sensitive interferometric nanostructure layers includes alternating high and low porosity layers.