Abstract: Objective To perform quantum dots(QDs)imaging of breast cancer cells and breast cancer tissue paraffin specimens by using nucleic acid aptamer W3 binding specificity on breast cancer cells. Methods The binding specificity of nucleic acid aptamer W3 to breast cancer cell lines was detected by flow cytometry, and based on the binding reaction principle of biotin and streptomyces avidin, the quantum dot targeting imaging of nucleic acid aptamer W3 on breast cancer cell lines and tissue specimens of clinical patients was observed by fluorescence microscopy, and its clinical significance was further analyzed. Results The nucleic acid aptamer W3 specifically binded to breast cancer cell lines with high malignancy,and after coupling quantum dots QD605(W3-QDs), it achieved targeted imaging of breast cancer cell lines and breast cancer tissues with high malignancy, and the fluorescence intensity of breast cancer tissues with high malignancy degree was significantly higher than that of breast cancer tissues with low malignancy. Conclusions The nucleic acid aptamer W3 may achieve target imaging of breast cancer after coupling quantum dots, which can be used for early diagnosis of breast cancer.

Key words: aptamer, breast cancer, quantum dot, targeted imaging