Labeling of polymer nanostructures for medical imaging: Importance of cross-linking extent, spacer length, and charge density

A study was conducted to demonstrate optimized conjugation of DOTA chelators onto shell cross-linked nanoparticles (SCK) in aqueous medium. Copper64labeling of DOTA-SCK conjugates was in the study to provide insights into the coupling chemistry, design of ligands, and transformation of SCKs into functional materials. Several SCK samples, with varying extents of cross-linking, SCK1-SCK8, were prepared from the self-assembly of amphiphilic diblock copolymers and poly(acrylic acid)-b-polystyrene (PAA-b-PS), with varying block lengths from 30-136 repeat units. Conjugation of each sample from SCK1 to SCK8 with DOTAamine molecules were performed through amidation chemistry.