In this paper, we present an innovative sensing nanomaterial for an interference localized surface plasmon resonance (iLSPR) sensor. The iLSPR is based on plasmonic gold nanoparticles with photonic thin-film multilayers of porous aluminum oxide (Al(2)O(3)) and aluminum (Al) on a substrate. With a controllable transparent Al(2)O(3) layer and a highly reflective Al layer, our new nanomaterial was able to detect refractive index (RI) changes of the surrounding environment and the specific interaction of biomolecules including biotin and avidin, 5- fluorouracil (5-FU) and its antibody, anti-5-fluorouracil (anti 5-FU), when the iLSPR surfaces were biologically functionalized. Our model nanostructure will open the way to display the plasmonic properties of other noble metal nanoparticles and to develop other functionally similar nanosensors, which could then be expanded into multiarrays.