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In this work, three new complexes [Ln2(L)3·H2O]n (where Ln = Nd(1)、Eu (2) and Sm (3)) have been synthesized by H2L (H2L = 1,1 ‘(1,4‐phenylene‐ bis [methylene])‐bis (pyridine‐3‐carboxylicaicd)) and were characterized by X‐ray single crystal diffraction and PXRD. The interaction of these complexes with FS DNA (fish sperm DNA) and the DNA binding constants of the complexes were determined using UV spectroscopy, indicating their ability to bind to FS DNA. The DNA binding constants k of the three complexes were 1.0186 × 104, 5.047 × 103, and 5.115 × 103, respectively. The results of UV spectrum showed that the complex 1–3 was bound to DNA through hydrogen bonding. The interaction of the complexes with FS DNA was studied by fluorescence spectroscopy. The stern‐volmer quenching values of complexes 1, 2, and 3 were 0.186, 0.093, and 0.114, respectively. Electrophoresis experiments showed that the three complexes could cleave DNA molecules. In addition, flow cytometry, and morphological apoptosis studies showed that the complex could induce apoptosis of HeLa tumor cells. Results all the three complexes had potential medicinal value.

Traditional single-fluorescence sensors have certain limitations in selectivity and sensitivity, and developing novel selfcalibration probes is highly required. Herein, a novel waterstabilized lanthanide metal-organic framework (MOF) sensor (Tb-BDOA) was selected, and its multiple emission peaks were used to self-calibrate sensing pesticide. Tb-BDOA emits green fluorescence at 445 nm,488 nm,545 nm,587 nm and 621 nm under the excitation of 280 nm. Different pesticides will cause different changes in the emission peaks of Tb-BDOA, so as to conveniently distinguish different pesticides and displays selfcalibration fluorescent response to nicosulfuron (NSF) and thiamethoxam (TMT). Besides the unique combination of each pesticide and ligand!Tb(III) emission intensity ratio showed significant correlation, which realized specific two-dimensional fingerprint recognition. At the same time, 3D code recognition is realized by drawing the changes of two ratios under different concentrations. As a result, the novel self-calibration sensor demonstrates effective recognition of NSF and TMT with excellent sensitivity and selectivity as well as great recycling ability. This provides a promising strategy for the development of new self-calibrating sensors.