Atomic force microscopy imaging of T4 bacteriophages on silicon substrates.

A new atomic force microscope incorporating microfabricated cantilevers and employing laser beam deflection for force detection has been constructed and is being applied to studies of biological material. In this study, T4 bacteriophage virus particles were deposited from solution onto electronic-grade flat silicon wafers and imaged in air with the microscope. Microliter droplets of the solution were deposited and either allowed to dry or removed with blotting paper. The images show both isolated viruses and aggregates of various sizes. The external structure as well as strands believed to be DNA streaming out of the virus could be observed. The construction of the microscope and its performance are also described.