Development of nanoparticle libraries for biosensing.

Magnetic and magnetofluorescent nanoparticles have become important materials for biological applications especially for sensing, separation, and imaging. To achieve target specificity, these nanomaterials are often covalently modified with binding proteins such as antibodies or proteins. Here we report on the creation of nanoparticle libraries that achieve specificity through multivalent modification with small molecules. We explore different synthetic routes to attach small molecules with anhydride, amine, hydroxyl carboxyl, thiol, and epoxy handles. We show that the derived nanomaterials have unique biological functions, possess different behaviors in cell screens, and can be used as substrates for biological screens.