Role of biofunctionalization and tracer cross-linking in magnetic particle spectrometry

In this paper, we present a ligand exchange and PEGylation approach for developing monodisperse MPI tracers (core size ~ 20nm) with the required reactive -NH
₂
and/or -SH functional groups on their surface. First, free carboxyl groups were introduced on the surface of the NPs through a silanization reaction. Then, a carbodiimide reagent (DCC) was used to bond the amine groups of the NH
₂
-PEG-NH
₂
or NH
₂
-PEG-SH molecules to these carboxyl groups.