Improved mass determination of isolated biological objects by transmission electron microscopy and scanning microdensitometry

A modification of the classical method of Bahr and Zeitler for dry mass determination of isolated biological objects is described. The method uses a conventional transmission electron microscope (TEM) and a computer-controlled scanning microdensitometer. The performance of the modified method has been investigated by applying it to model specimens (polystyrene latex spheres). The method offers significant improvements over the existing TEM-based mass determination method.