In vivo real-time confocal microscopy for target-specific delivery of hyaluronic acid-quantum dot conjugates.

UNLABELLED Hyaluronic acid (HA), which is a biocompatible, biodegradable, and linear polysaccharide in the body, has been widely used for various biomedical applications. In this work, real-time bioimaging for target-specific delivery of HA derivatives was carried out using quantum dots (QDs). In vitro confocal microscopy of HA-QD conjugates confirmed the intracellular delivery of HA derivatives to B16F1 cells with HA receptors by HA-receptor-mediated endocytosis. Furthermore in vivo real-time confocal microscopy of HA-QD conjugates successfully visualized the target specific delivery and accumulation of HA-QD conjugates from the fluorescence-labeled blood vessels to the liver tissues. The authors could confirm the feasibility of HA derivatives as a target-specific intracellular drug-delivery carrier for the treatment of liver diseases and the in vivo real-time confocal microscopy as a new bioimaging tool for various drug-delivery applications. FROM THE CLINICAL EDITOR This study demonstrates the possibility of labeling hyaluronic acid with quantum dots for visualization and for targeted intracellular drug delivery in liver disease models.