A fluorescent biosensor based on prismatic hollow Metal-polydopamine frameworks and 6-carboxyfluorescein (FAM)-labeled protein aptamer for CA15-3 detection

The effective detection of CA15-3 is of great significance for the postoperative monitoring and early diagnosis of breast cancer. Here, a fluorescent biosensor based on the fluorescence resonance energy transfer (FRET) between the prismatic hollow Metal-polydopamine frameworks (PHMPF) and 6-carboxyfluorescein (FAM)-labeled protein aptamer (FAM-Apt) was established to detect CA15-3. Characterization of SEM, TEM, EDS, FT-IR, XRD and XPS confirmed that the synthesized PHMPF was a polyhedral prismatic hollow organometallic frame containing the elements of C, N, O, and Co. PHMPF can quench the fluorescent group modified on the aptamer efficiently. Under optimized conditions, the proposed fluorescent biosensor can detect CA15-3 low to 2.56 × 10 −5 U mL −1 . In addition, the excellent selectivity and spiked experiments indicate the proposed biosensor owns potential applications for the clinical diagnosis of tumor markers in body fluids.