Fluidic force microscopy for the injection of femtoliter volumes into single cell nuclei is described by T. Zambelli, J. A. Vorholt, and co-workers on page 1904. The pyramid of a microfluidic AFM cantilever is precisely inserted into the cell nucleus under force control, while a solution loaded in the probe is delivered to the nuclear compartment through the application of a pressure pulse. Efficient injection with simultaneous recording of cell indentation events, as well as tunable volume release, are demonstrated. Cell transformation by injection of plasmid DNA is validated by gfp expression.