The interaction between magnetic iron oxide nanoparticles (MION) and CdTe quantum dots (QDs) was studied by fluorescence and UV-visible absorption spectra. The results showed that the fluorescence of CdTe QDs was strongly quenched by MION. The quenching mechanism was discussed to be a static quenching process, which was proved by the quenching rate constant (K_q＝7.68×10¹⁵ mol•L^－1•s^－1) and UV-vis absorption spectra. According to Lineweaver-Burk equations at different temperatures, the thermodynamic parameters (?H^?＝21.6 kJ•mol^－1, ?S^?＝210.3 J•mol^－1•K^－1 and ?G^?＝－41.1 kJ•mol^－1, 298 K) were obtained. It was found that the process of binding was a spontaneous process with an electrostatic interaction.

Key words: magnetic iron oxide nanoparticle, CdTe quantum dot, interaction, thermodynamic parameter