A ratiometric aptasensor for simultaneous determination of two estrogens based on multicolor upconversion nanoparticles

Different environmental estrogens (EEs) may coexist in the same foodstuff, necessitating the establishment of a simultaneous detection method. Although there are numerous studies on the detection of EEs, few was reported on the determination of two or more estrogens at the same time except HPLC . Our efforts have been made to develop a ratiometric aptasensor based on multicolor lanthanide-doped upconversion luminescence nanoparticles (UCNPs) to realize simultaneous and sensitive detection of two EEs (bisphenol A and 17β-estradiol). Three types of core-shell UCNPs with excellent luminous properties and distinct emitting colors were successfully synthesized via doping with various lanthanide ions , two of which were conjugated with specific aptamers and act as energy donors, while another one served as a reference. Because of their excellent luminescence quenching performance, ultra-thin metallic MoS 2 nanosheets were selected as the energy acceptor. Thus, a ratiometric luminescence aptasensor was established and successfully used for the simultaneous detection of two estrogens in tap water and milk samples, demonstrating its considerable practical application value.