Abstract
Estrogen receptor alpha (ERα) is an important biomarker for breast cancer which is positive in over 75% of breast cancer cases. In this study, an electrochemical biosensor was constructed for sensitive detection of ERα based on the signal amplification of AuNPs-SWCNT nanocomposites and hemin@HKUST-1. AuNPs-SWCNT was served as a conductive substrate, and be used to immobilize the aptamer (Apt) by an Au–S bonding. Then, Apt, ERα and antibody (Ab) formed a sandwich composite structure through specific recognition and immobilized on the electrode. The hemin@HKUST-1 was introduced into the biosensor via an amide bond with Ab and acted as the signal molecule. AuNPs-SWCNT could significantly enhance the conductivity of the electrode and the large specific surface area of HKUST-1 enabled it to load more hemin, and greatly improved the sensitivity of the biosensor. The detection limit (LOD) of the biosensor could reach 27.8 fg·ml−1 after optimization of the conditions, with the current intensity and the logarithm of the ERα concentration exhibited a good linear relationship between 100 fg·ml−1 and 100 ng·ml−1. In addition, the biosensor possessed excellent selectivity, stability, reproducibility and Interference immunity. More importantly, it shows great application potential in practical detection.
Funder
the Project of Tackling of Key Scientific and Technical Problems in Henan Province
the National International Cooperation Base
Publisher
The Electrochemical Society
Subject
Materials Chemistry,Electrochemistry,Surfaces, Coatings and Films,Condensed Matter Physics,Renewable Energy, Sustainability and the Environment,Electronic, Optical and Magnetic Materials