Abstract
Hyaluronan (HA) represents an interesting polymer for nanoparticle coating due to its biocompatibility and enhanced cell interaction via CD44 receptor. Here, we describe incorporation of oleate-capped beta-NaYF4:Yb3+, Er3+ nanoparticles (UCNP-OA) into amphiphilic HA by microemulsion method.
Resulting structures have a spherical, micelle-like appearance with a hydrodynamic diameter of 180 nm. UCNP-OA-loaded HA micelles show a good stability in PBS buffer and cell culture media.
The intensity of green emission of UCNP-OA-loaded HA micelles in water is about five times higher than that of ligand-free UCNP, indicating that amphiphilic HA effectively protects UCNP luminescence from quenching by water molecules. We found that UCNP-OA-loaded HA micelles in concentrations up to 50 mu g mL(-1) increase cell viability of normal human dermal fibroblasts (NHDF), while viability of human breast adenocarcinoma cells MDA-MB-231 is reduced at these concentrations.
The utility of UCNP-OA-loaded HA micelles as a bio-imaging probe was demonstrated in vitro by successful labelling of NHDF and MDA-MB-231 cells overexpressing the CD44 receptor.