An integrated approach to the study of living cells by atomic force microscopy

We describe a technique for studying living cells with the atomic force microscope (AFM) in tapping mode using a thermostated, controlled-environment culture system. We also describe the integration of the AFM with bright field, epifluorescence and surface interference microscopy, achieving the highest level of integration for the AFM thus far described. We succeeded in the continuous, longterm imaging of relatively flat but very fragile cytoplasmic regions of COS cells at a lateral resolution of about 70 nm and a vertical resolution of about 3 nm. In addition, we demonstrate the applicability of our technology for continuous force volume imaging of cultured vertebrate cells. The hybrid instrument we describe can be used to collect simultaneously a diverse variety of physical, chemical and morphological data on living vertebrate cells. The integration of light microscopy with AFM and steady-state culture methods for vertebrate cells represents a new approach for studies in cell biology and physiology.