High-Throughput Characterization of Microcantilever Resonator Arrays for Low-Concentration Detection of Small Molecules

Microcantilever-based biosensors have shown the ability of highly sensitive label-free detection by allowing the transduction of a target mass into a resonant frequency shift. Even if they have been widely adopted in the last years as high sensitive mass detectors, precision and specificity of such tools are often inadequate. A new platform able to precisely characterize in dynamic mode several of these micromechanical resonators is here presented. Consequently, to the examination of the main parameters involved in a measurement, repeatability and reproducibility of the automated cantilever-based system were estimated. The reported analyses demonstrated that the uncertainty of the system could be reduced to a standard deviation of 6.5 × 10-6(parts per million). Thanks to its fine precision, the here-proposed sensing platform was able to detect aflatoxins in naturally contaminated nuts at concentrations as low as 40 pg/mL, nearly two orders of magnitude more sensitive than previous attempts reported in the literature with similar devices.