Scanning ion conductance microscopy (SICM) is a super-resolution live imaging
technique that uses a glass nanopipette as an imaging probe to produce 3D images of cell surface.
SICM can be used to analyze cell morphology at nanoscale, follow membrane dynamics, precisely
position an imaging nanopipette close to a structure of interest, and use it to obtain ion channel
recordings or locally apply stimuli or drugs. Practical implementations of these SICM advantages,
however, are often complicated due to the limitations of currently available SICM systems that
“inherited” their design from other scanning probe microscopes in which the scan assembly is
placed right above the specimen. Such arrangement makes the setting of optimal illumination
necessary for phase contrast or the use of high magnification upright optics difficult. Here we
describe the designs that allow mounting SICM scanhead on a standard patch-clamp
micromanipulator and imaging the sample at an adjustable approach angle. This angle could be as
shallow as the approach angle of a patch-clamp pipette between a water immersion objective and
the specimen. Using this angular approach SICM, we obtained topographical images of cells grown
on non-transparent nanoneedle arrays, of islets of Langerhans, and of hippocampal neurons under
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upright optical microscope. We also imaged previously inaccessible areas of cells such as the side
surfaces of the hair cell stereocilia and the intercalated disks of isolated cardiac mocytes, and
performed targeted patch-clamp recordings from the latter. Thus, our new angular approach SICM
allows imaging of living cells on non-transparent substrates and a seamless integration with most
patch-clamp setups on either inverted or upright microscopes, which would facilitate research in
cell biophysics and physiology.