Microcantilever based biochemical sensors rely on accurately detecting the selective binding of small amounts of the target analyte to a functionalized microcantilever. Commonly, the added mass of the bound analyte is detected by measuring accompanying shift in cantilever resonant frequency. In this paper we explore the possibility of using Anderson or mode localization in coupled oscillator arrays as a potentially more sensitive method for detecting the added mass. According to this method, the eigenvectors of an array of coupled, nominally identical cantilevers are expected to be extremely sensitive to small disorder such as that introduced by the added mass of the target biochemical analyte. A simple lumped parameter model of the cantilever array is used to establish theoretical feasibility of the method. The effects on the eigenvector sensitivity of initial statistical variability introduced due to inherent manufacturing tolerances are investigated. Experimental results are presented for a two cantilever array laser fabricated out of gold foil, and the results compared to theoretical expectations. Both the theoretical and experimental results indicate that added mass induced shifts in eigenvectors of such arrays can be orders of magnitude more sensitive than the resonance frequency shifts.
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