Synthesis and In Vivo Fate of Zwitterionic Near‐Infrared Fluorophores

To address two fundamental and unsolved problems in optical imaging (nonspecific uptake of near-infrared fluorophores by normal tissues and organs and incomplete elimination of unbound targeted fluorophores from the body), novel zwitterionic near-infrared fluorophores (e.g., ZW800-1) were synthesized and their performance compared in vivo to conventional molecules (e.g., ICG) as a function of charge, charge distribution, and hydrophobicity (see picture).