Diatom-based Sensors: Organic/Inorganic Interfaces and Health Science Application

Nanopore membranes exhibit tremendous potential for applications such as molecular filtration and DNA sequencng studies. However, the large-scale manufacturing of these nanopore membranes using MEMS technology is challenging, requiring slow serial electron or ion-beam patterning. Marine diatoms on the other hand feature biomineralized silica shells with the smallest pore diameters being 40 nm. Their hierarchical pore architecture makes these nanomembranes exceptionally mechanically stable. Moreover, the nanopores are homogeneous in size and have a low aspect ratio, enabling fast diffusion-driven transport. The drawback of the biomineralized structures is that they are single entities, which have to be combined with a support structure to integrate them into a microsystem. Our solution consists of immobilizing the biomineralized structures on silicon substrates. With the diatom shells growing up to 200 μm in diameter, they are easy to manipulate on the oxidized silicon surface. Through-wafer via holes with...