Breast cancer is one of the most critical threats to the health of women, and the development of new
methods for early diagnosis is urgently required, so this paper reports a method to detect Michigan
cancer foundation-7 (MCF-7) human breast cancer cells with considerable sensitivity and selectivity
by using electrochemical technique. In this method, a mucin 1 (MUC1)-binding aptamer is adopted to
recognize MCF-7 human breast cancer cells, while enzyme labeling is employed to produce amplified
catalytic signals. The molecular recognition and the signal amplification are elaborately integrated by
fabricating an aptamer–cell–aptamer sandwich architecture on an electrode surface, thus a biosensor
for the detection of MCF-7 is fabricated based on the architecture. The detection range can be from 100
to 1 × 107 cells, and the detection limit can be as low as 100 cells. The method is also cost-effective and
conveniently operated, implying potential help for the development of early diagnosis of breast cancer