Nano Cell-Biopsy Using Nanostraws

To investigate cellular composition, the standard method today is to lyse cells. This implies that a set of cells only can be measured once. Longitudinal studies are performed by having several cell cultures and lysing them at different time points. This opens up for phenotype variation between the different cultures, which may impact the result negatively. By using nanostraw electroporation (NS-EP), the same set of cells could instead be monitored over time while maintaining a high cell viability [2]. Nanostraws (NS) are vertical hollow nanostructures protruding from a polycarbonate membrane, which allow for direct intracellular access when cells are seeded on top of them. The devices, with NS and cells, are exposed to a pulsed electric field which open up pores in the cell membrane [3] and has an electrophoretic effect on the charged biomolecules inside the cells. Successful cell sampling, using NS-EP, has been reported for various cell types, both primary<br/>cells and cell lines [2]. In comparison to other cell sampling methods, such as atomic force microscopy and nanopipettes, nanostraws can produce larger throughput [1]. Here, NS-EP has been used to extract insulin mRNA from beta cells. The devices were placed on a reservoir containing buffer, which after electroporation was extracted and analyzed using quantitative real-time PCR (qPCR). The results show that we successfully<br/>managed to extract insulin mRNA from beta cells using this method. When optimized, this method could be used for longitudinal studies in diabetes research, studying how the cells respond to certain treatments over time.<br/>[1] P. Actis. Small Methods, 2(3):1700300, 2018.<br/>[2] Y. Cao et al. PNAS, 114(10):E1866–E1874, 2017.<br/>[3] E. Hebisch et al. Small, 17(7):2006421, 2021.