Crosslinking of viral nanoparticles with “clickable” fluorescent crosslinkers at the interface

Cu (I) catalyzed alkyne-azide cycloaddition (CuAAC) reaction, a typical “click“ reaction, is one of the modular synthetic approaches which has been broadly used in various organic syntheses, medicinal chemistry, materials development and bioconjugation applications. We have for the first time synthesized two dialkyne derivatized fluorescent crosslinkers which could be applied to crosslink two biomolecules using CuAAC reaction. Turnip yellow mosaic virus, a plant virus with unique structural and chemical properties, was used as a prototypical scaffold to form a 2D single layer at the interface of two immiscible liquids and crosslinked with these two linkers by the CuAAC reaction. Upon crosslinking, the fluorescence of both linkers diminished, likely due to the distortion of the polymethylene backbone, which therefore could be used to indicate the completion of the reaction.