Fabrication of In-Channel High-Aspect Ratio Sensing Pillars for Protrusive Force Measurements on Fungi and Oomycetes

This paper reports the fabrication and application of a Lab-on-a-Chip platform containing single-elastomeric micropillars in channel constrictions, which enable the measurement of protrusive forces exerted by individual fungal hyphae. We show the device design, the fabrication process, and photoresist optimization required to adapt the microfluidic platform to relatively thin hyphae. To demonstrate the applicability of the devices, the oomycete
Achlya bisexualis
and the fungus
Neurospora crassa
were cultured on PDMS chips. Devices were combined with confocal imaging to study the interaction of
A. bisexualis
hyphae with the measurement pillars. The force exerted by individual hyphae of
N. crassa
was measured and compared with a hyphal growth rate and diameter. The platform provides a new tool to help understand the molecular processes that underlie protrusive growth and this may present new ways to tackle the pathogenic growth of these organisms and thus combat the loss of diversity that they cause. This paper is based on the conference proceedings presented at the 31st IEEE International Conference on Micro Electro Mechanical Systems (MEMS 2018), Belfast. [2018-0090]