A novel non-biological dual identification system based on SBE-β-CD@CdTe for the simultaneous detection of multiple steroids in environmental water.

Steroid hormones (SHs) have posed a serious threat to ecosystems and human health. The development of rapid assays for the detection of different SHs is urgent for the ecological and human health. However, the rapid detection of SHs residues in the environment is still a challenge due to the wide variety of SHs and their poor electroactivity. Herein, we introduced a novel nonbiological sensing system utilizing sulfobutyl β-cyclodextrin as a recognition unit for the simultaneous and sensitive detection of multiple SHs in water. The mechanism study showed that the sulphonate group in the prepared SBE-β-CD@CdTe/P(L-Arg)/GCE has a high affinity for the Δ4-3-ketone group in SHs, while the hydrophobic cavity could interact with the unsaturated bond of the C-17 side chain of SHs, resulting in a dual recognition system. Further, the analytical performance of this method was evaluated using 30 different substances, including 24 SHs and 6 steroidal analogues. The results showed that this sensor could simultaneously detect a wide range of SHs containing the Δ4-3-ketone group. The sensor was then applied to simultaneously monitor dexamethasone, fluoxymesterone, and chlormadinon in environmental water samples, and the results were satisfactory with detection limits of 4.1 nmol L-1, 3.4 nmol L-1, and 7.7 nmol L-1, respectively. Meanwhile, the SBE-β-CD@CdTe/P(L-Arg) sensing system exhibited a strong specificity for the target substances. Thus, this sensing system enables the rapidly identifying multiple SHs in the aquatic environment and has great potential applications in environmental studies, illicit addition and drug analysis. In addition, this study provides a new idea and theoretical basis for the construction of on-line monitoring method for strong physiologically active components.