Preparation of bimetal–polydopamine organic frameworks with core–shell structure and their application in HER2 detection

Abstract

Human epidermal growth factor receptor 2 (HER2) is one of the specific markers of breast cancer, which is of great significance to the early diagnosis and prognosis of breast cancer. Here, a fluorescence biosensor was established to detect HER2 based on the fluorescence resonance energy transfer (FRET) and photoinduced electron transfer (PET) occurred between bimetal-polydopamine organic frameworks with core-shell structure Au@PDA@UiO-66 and Cy5 fluorophore in HER2-Cy5-Apt. Au@PDA@UiO-66 owns high-efficiency fluorescence quenching ability due to its large specific surface area and strong adsorption of single-stranded DNA. When the target appears, the fluorescence recovery space mediated by the target is large, so the proposed biosensor has better sensitivity in theoretically. Under optimized conditions, the proposed fluorescent biosensor can detect the HER2 in a range of 0.005 ng/mL to 15 ng/mL, with an actual detection limit as low as 0.005 ng/mL. Corresponding selective experiments, reproducible experiments, and spiked experiments perform well, showing its great potential in HER2 detection.