Shemyakin Institute of Bioorganic Chemistry 1 article published in JoVE Biology FSL Constructs: A Simple Method for Modifying Cell/Virion Surfaces with a Range of Biological Markers Without Affecting their Viability Deborah A. Blake1, Nicolai V. Bovin2, Dan Bess1, Stephen M. Henry1 1Biotechnology Research Institute, AUT University and KODE Biotech Ltd, 2Shemyakin Institute of Bioorganic Chemistry RAS, Moscow, Russia Function-Spacer-Lipid (FSL) constructs allow the surface characteristics of living cells and virions to be modified without loss of vitality. The method requires only simple contact of an FSL construct solution with a cell/virion and spontaneous and stable surface incorporation occurs.