Abstract:

Hyaluronic acid(HA) has been known as an important element in tumor growth, because its receptor, CD44, is over expressed on many kinds of tumor cells. Thus, the interaction between HA and CD44 has been used for HA-targeted therapy and imaging of malignancy. In order to establish a method to detect the HA receptor in the cell and further to image the tumor cell, hyaluronic acid-quantum dot conjugate was synthesized and applied in tumor imaging. The quantum dot(CdSe/ZnS) was prepared in aqueous solution with cysteamine as stabilizer, and then conjugated with HA through amidation reaction between the carboxyl groups of HA and amino groups of QD. The average size of HA-QD conjugate nanoparticle was about 10 nm and emission wavelength was 657 nm. According to in vitro cell experiment, it was proved that the HA-QD conjugate could effectively target on the LA795 cells and subsequently internalized itself into the cytoplasm via HA receptor-mediated endocytosis. As its cancer targeting efficiency showing in our experiment, it suggests the potential of HA-QD conjugate applying in imaging and visualization of changes for cancer diagnosis.

Key words: Hyaluronic acid(HA), Quantum dot(QD), Tumor cell, Fluorescence imaging