The metrological traceability of materials has become one of the most interesting topic for researchers studies and a valid instrument for the reliability of the results of the tests. The definition of new samples and the regulation of industrial measurement instruments and systems require to follow a lot of steps for an accurate calibration. INRiM works for nanostructure tests, exploiting the potential of a metrological Atomic Force Microscopy (AFM). The first part of this work is essentially based on several kinds of measurements on Tobacco Mosaic Virus (TMV), in order to check if this virus could become an ideal reference material.