Device for filamentous fungi growth monitoring using the multimodal frequency response of cantilevers

Filamentous fungi cause opportunistic infections in hospital patients. A fast assay to detect viable spores is of great interest. We present a device that is capable of monitoring fungi growth in real time via the dynamic operation of cantilevers in an array. The ability to detect minute frequency shifts for higher order flexural resonance modes is demonstrated using hydrogel functionalised cantilevers. The use of higher order resonance modes sees the sensor dependent mass responsivity enhanced by a factor of 13 in comparison to measurements utilizing the fundamental resonance mode only. As a proof of principle measurement, Aspergillus niger growth is monitored using the first two flexural resonance modes. The detection of single spore growth within 10 h is reported for the first time. The ability to detect and monitor the growth of single spores, within a small time frame, is advantageous in both clinical and industrial settings.