Ratiometric persistent luminescence aptasensors for carcinoembryonic antigen detection

NIR-emitted ZnGa₂O₄:Cr³⁺ persistent luminescence nanoparticles (ZGC NPs) coated with polydopamine (ZGC@PDA NPs) were designed featuring internal reference and quenching ability. Sr-doped Zn₂GeO₄ persistent luminescence nanorods (ZGO:Sr NRs) served as detection probes, which exhibited blue emission. The decay times and intensity of luminescence of ZGO:Sr NRs were optimized to acquire desired luminescence properties. An aptamer-guided ratiometric persistent luminescence sensor with the LOD (0.46 pg mL^-1) was established to detect carcinoembryonic antigen (CEA). This developed ratiometric aptasensor based on persistent luminescence nanomaterials (PLMs) does not only use the afterglow properties of nanomaterials to avoid the interference of autofluorescence but also precludes the interference of certain factors in the detection environment on the luminescence intensity due to the introduction of a reference signal, and is suitable for early screening of tumor markers in serum samples. Moreover, the optimization of luminescence properties, especially for luminescence decay times, provides a way for the fabrication of multiple persistent luminescence materials in the application of time-resolved fluorescence technology. Graphical abstract Construction of ZGO:Sr NR- and ZGC@PDA NP-driven ratiometric aptasensor for CEA detection.