- This paper reports the development of a novel smectite-polymer nanocomposite (SPN) microstrip sensor for both rapid quantification and long-term monitoring of aflatoxins. The smectite was modified with Ba 2+ cation exchange to improve its aflatoxin adsorption. SPN thin-films were synthesized on silicon substrates via layer-by-layer self-assembly. SPN microstrip arrays were patterned on glass substrates using stencil masks and enclosed in a microfluidic channel. This reduces the diffusion length and the adsorption time of aflatoxins, thereby resulting in fast response time (< 10 min). A simple fluorometric quantification of aflatoxin concentration based on incident intensity modulation was developed to eliminate the need of a sophisticated fluorometer. A low detection limit of 6.09 ppb and a wide linear range of 580 ppb for aflatoxin B1 have been achieved. 2013 IEEE.