Facile fabrication of luminescent hyaluronic acid with aggregation-induced emission through formation of dynamic bonds and their theranostic applications.

Aggregation-induced emission (AIE) is an abnormal phenomenon, which has been extensively explored for various applications. Taken advantage of the unique AIE feature, a number of luminescent nanoprobes with strong fluorescence intensity could thus be fabricated through different strategies; however, the fabrication of AIE-active carbohydrate polymers is still challenge owing to the poor solubility of carbohydrate polymers in most of organic solvents. In this work, a rather facile strategy has been developed for fabricating AIE-active sodium hyaluronate (Sh) through the formation of dynamic phenyl borate between the phenylboronic acid groups of AIE dye (An-B(OH))) and Sh in a "one-pot" route. This reaction could occur under low temperature, air atmosphere and in the present water. The physicochemical properties, biocompatibility, biological imaging and drug delivery performance of the final An-Sh fluorescent organic nanoparticles (FNPs) were confirmed by different characterization techniques. Results suggested that An-Sh FNPs possess high water dispersibility, strong fluorescence, and good biocompatibility. These excellent properties make An-Sh FNPs great potential for biological imaging and controlled drug delivery applications. In conclusion, we have developed a facile one-pot strategy for the preparation of AIE-active FNPs through the formation of dynamic bonds in rather mild experimental conditions. The outstanding properties and performance of An-Sh FNPs make them promising candidates for biological imaging and controlled drug delivery applications.