Atomic force microscopy and biosensing, from nanoscale imaging to nanobiosensors

W its ability to observe, manipulate and explore the structures and dynamics of biological systems at subnanometre resolution, atomic force microscopy (AFM) has produced a wealth of new opportunities in biosensing. Evolving from an imaging technique to a multifunctional ‘lab-on-a-tip’, AFM-based force spectroscopy is increasingly used to study the mechanisms of molecular recognition and to probe the chemical groups and dynamics of receptor-ligand interactions in living systems. In the past few years, the general applicability of cantilever nanosensors has been demonstrated for probing DNA hybridization, and detecting medically important biomarkers, such as prostate-specific antigens, cardiac biomarker proteins, DNA binding proteins and mRNA markers for cancer progression. AFM cantilever arrays allow the detection of bioanalytes with picomolar sensitivity, opening new avenues for medical diagnostics and environmental monitoring. Here the author will review the fascinating opportunities offered by the rapid advances in the AFM-biosensing field and the open challenges in AFM-biosensing technology.