Eytham Souibgui, Sergio Leal-Ortiz
Major advances in nanotechnology have facilitated the development of powerful tools to study biology at the cellular level. Our nanostraw platform provides intracellular access to the cytosol to introduce exogenous components such as DNA, proteins and synthetic molecules like dyes directly into the cells. This technology has shown promise in high efficiency mammalian cell transfections. Recently, the nanostraw platform was also applied to extract intracellular cell components like mRNA and proteins from single cell.
Nanostraws with different dimensions i.e. length and diameter can be optimized to interface with different cell types including plant cells. Plant cells are unique and different from mammalian cells as they are surrounded by cell walls which serve as barriers that prevent easy delivery of exogenous components. However, nanostraws with longer lengths can penetrate through this barrier to deliver cargoes into the cells. This technology is a promising tool for applications such as genetic engineering of plants and subcellular localization of cargoes.
Figure 1. Cargo delivery in tobacco leaf cells using nanostraw system
The nanostraw system used for cargo delivery into plant cells is composed of a chamber fabricated with nanostraw-embedded membrane. Cargo is load into the chamber then a slight pressure is apply on the device to allow nanostraws penetration into the cells and cargo diffusion through nanostraws.
Figure 2. Scanning electron microscopy micrographs of nanostraw membranes
Straw fabrication process flow begins with a nanoporous polycarbonate membrane, proceeds with conformal alumina atomic layer deposition, then an alumina specific directional reactive ion etch, and concludes with a polycarbonate specific directional reactive ion etch.
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