Biofunctionalization of Fluorescent Rare‐Earth‐Doped Lanthanum Phosphate Colloidal Nanoparticles

Approximately eight avidin molecules are conjugated to each Ce/Tb-doped lanthanum phosphate nanoparticle (NP) through the formation of amide bonds (see scheme). This biofunctionalization process comprises modification of the LaPO4 NPs with 6-aminohexanoic acid (AHA) to confer colloidal stability, activation of the AHA carboxy groups by 1-ethyl-3-[3-dimethylaminopropyl]carbodiimide, and avidin conjugation.