Trastuzumab conjugates of H3DFO labelled with 89Zr have been successfully employed to image HER2 positive tumours and assess HER2 expression levels.24,39,40 Therefore native trastuzumab was utilised here as a model antibody to assess the properties of a 89Zr-labelled tris(hydroxypyridinone) conjugate. Here, ERBB2 is linked to neoplasm.