This paper described the physicochemical characterization and application of quantum dots (CdSe/ZnS, QDs) whose
surface were hydrophilic modified by mercaptoundecanoic acid (MUA). The stability kinetics of MUA-coated QDs
(MUA-QDs) in aqueous solution was studied as a function of MUA-QDs concentration, type of light exposed, pH
conditions and temperatures. The results show that the optimum concentration range of MUA-QDs is 0.5 to 1 mg/mL.
We found that no obvious difference of fluorescence intensity was detected in MUA-QDs stored respectively at 4°C,
24°C and 44°C (8-hour). When they were exposed to UV light (312 nm) for 8 hr, their fluorescence intensity was shown
serious decay. Moreover, the results showed that the pH of maximum stability of MUA-QDs in buffer solutions was 8.
Finally, MUA-QDs had been endocytosis into H9c2 cells, a permanent cell line derived from rat cardiac tissue, for cell
imaging application, the results provided the benefit to apply MUA-QDs in medical areas.