Abstract
Pipettes, in one form or another, have been used for sampling and transferring liquids in biology and chemistry for almost three centuries. The functionality of this rather simple tool has been dramatically expanded with the invention of scanning ion conductance microscopy (SICM). SICM uses ion current flowing out of the tip of a glass nanopipette (pipette with tip diameter < 100 nm) filled with electrolyte to detect presence of a surface in a noncontact fashion. By scanning the sample in x-y plane and moving the nanopipette up and down on the z-axis the SICM recreates 3D topography image of the sample surface. We have shown that scanning nanopipettes are capable of reproducing 3D topography of complex, soft, live biological samples such as neuronal networks or inner ear hair cells1 at resolution better than atomic force microscopy2. We have successfully combined scanning nanopipettes with electrophysiology, fluorescence microscopy, and elasticity mapping to record for the first time electrical activity at submicron synaptic terminals3, and to visualise highly dynamic interactions of cellular membrane with nanostructured materials4,5. Recently, we have established the use of nanopipettes for 3D printing of micro to sub-microscale conductive polymer structures with potential use for interfacing with excitable cells. All these developments are only just beginning to open a new window into the life at nanoscale and our understanding of the nano-bio interface as well as offering new possibilities for precisely engineering interfaces between single cells and man-made electronic for therapeutic purposes or synthesis of entirely new bioelectrical circuits.