ABSTRACT
Conjugation chemistry is critical for covalent linking of nanoparticles with chemicals/biochemicals of interest. This chapter summarizes various conjugation chemistries and standard procedures for covalent conjugation of chemicals/biochemicals with coated nanoparticles. These conjugation chemistries can be adapted in transforming coated nanoparticles to functional nanoparticles. Conjugation chemistries are selected based on simplicity, effectiveness and general applicability to different nanoparticles. Conjugation methods include reaction of primary amine-terminated nanoparticles with N-hydroxysuccinamide (NHS)-based reagents, EDC (1-ethyl-3-(3-(dimethylamino)propyl)carbodiimide chloride) coupling between primary amine-terminated nanoparticles and carboxyl-bearing molecules, glutaraldehyde-based conjugation between primary amine-terminated nanoparticles and primary amine-bearing molecules, di-NHS-based conjugation between primary amine-terminated nanoparticles and primary amine-terminated molecules, 4-maleimidobutyric acid N-hydroxy succinimide ester (MAL-but-NHS)-based conjugation between primary amine-terminated nanoparticles and thiol-bearing molecules, Schiff-base reaction between primary amine-terminated nanoparticles and aldehyde-bearing molecules, epoxide-based reactions, disuccinimidyl carbonate (DSC)-based conjugation, isothiocyatate–based conjugation, Michael addition of thiolated molecules with polydopamone-coated nanoparticles, polymer coating using designed monomers, chloroformylate-based reactions and thiol-based approaches. In particular, standard conjugation procedures are described that produce a variety of nanobioconjugates. The described conjugation approaches offer general guidelines to prepare different nanobioconjugates and can be adapted to a new generation of nanoparticles of interest.
