Joint Forces of HR-Spicp-MS and EAF4-MALS for Characterization of Gold Nanorods Conjugated with Synthetic Glycopolymers

Abstract

As the diversity of nanomaterials is wide and their size can vary by 2 orders of magnitude (1−100 nm), the development of new and advanced analytical tools for their in-depth characterization is of paramount importance, allowing a fundamental understanding of their structure, further alteration and degree of chemical surface functionalization. Herein, we present a new strategy for characterization of gold nanorods (GNRs) that are of specific interest for biomedical applications due to their unique size-dependent longitudinal surface plasmon resonance band in the visible to near-infrared spectral region. More precisely, we characterized GNRs conjugated with short and long synthetic glycopolymers for biosensing of lectins in terms of particle size, coating thickness, and/or mobility properties in comparison with the bare GNRs. This endeavor requires a multidisciplinary approach including a new comprehensive set of fit-for-purpose analytical tools being high-resolution single-particle inductively coupled plasma-mass spectrometry (HR-spICP-MS) and electrical asymmetric-flow field-flow-fractionation hyphenated to a multi-angle light scattering detector (EAF4-MALS). GNRs were separated and characterized via EAF4-MALS in terms of their size and charge, while HR-spICP-MS provided information on the particle number density, size, size distribution, and the dimensional characterization. In addition, EAF4-MALS appears to be suitable for estimating coating thickness of glycoconjugated GNRs.