A Structure-Function Relationship for the Optical Modulation of Phenyl Boronic Acid-Grafted, Polyethylene Glycol-Wrapped Single-Walled Carbon Nanotubes

Abstract

Phenyl boronic acids (PBA) are important binding ligands to pendant diols useful for saccharide recognition. The aromatic ring can also function to anchor an otherwise hydrophilic polymer backbone to the surface of hydrophobic graphene or carbon nanotube. In this work, we demonstrate both functions using a homologous series of seven phenyl boronic acids conjugated to a polyethylene glycol, eight-membered, branched polymer (PPEG8) that allows aqueous dispersion of single-walled carbon nanotubes (SWNT) and quenching of the near-infrared fluorescence in response to saccharide binding. We compare the 2-carboxyphenylboronic acid (2CPBA)