Max Planck Institute for the Science of Light (MPL) 1 article published in JoVE Engineering Label-Free Imaging of Single Proteins Secreted from Living Cells via iSCAT Microscopy André Gemeinhardt1, Matthew P. McDonald1,2, Katharina König1,3, Michael Aigner4, Andreas Mackensen4, Vahid Sandoghdar1,3 1Max Planck Institute for the Science of Light (MPL), 2Area of Scientific Learning, Milligan College, 3Department of Physics, Friedrich Alexander University Erlangen-Nuremberg, 4Department of Internal Medicine 5, Hematology and Oncology, Friedrich Alexander University Erlangen-Nuremberg (FAU), University Hospital Erlangen We present a protocol for the real-time optical detection of single unlabeled proteins as they are secreted from living cells. This is based on interferometric scattering (iSCAT) microscopy, which can be applied to a variety of different biological systems and configurations.
