2-Nitroterephthalato-based uranyl coordination polymers: Selective luminescent sensing for vitamin B5 and Cr2O72–.

Under solvothermal conditions, a series of new uranyl coordination polymers based on 2-nitroterephthalic acid (H 2 ntp) and additional auxiliary ligands were successfully synthesized, which can be denoted as (UO 2)(ntp)(dm-phen) (1), (Hphen) 2 ∙[(UO 2)(ntp) 1.5 ] 2 (2), (Hphen) 2 ∙[(UO 2) 2 (ntp) 3 ]∙(H 2 O) 2 (3), and (Hphen) 2 ∙[(UO 2) 2 (ntp) 2.5 ] 2 ∙(H 2 O) 2 (4) (dm-phen = 4,7-dimethyl-1,10-phenanthroline, phen = 4,7-phenanthroline). The characteristics of as-prepared compounds were revealed by single crystal and powder X-ray diffraction, thermogravimetry, infrared spectroscopy and luminescent measurement. Furthermore, Compound 2 presents excellent sensitivity and selectivity to sense vitamin B 5 (VB 5) and Cr 2 O 7 2− anion as a dual-functional luminescent sensor in aqueous solution. 2 is the first turn-on luminescent sensor for detecting VB 5 with a low detection limit (LOD) of 1.39 μM, and the experimental detection range was 10–90 μM. In addition, in the linear range of 50–450 μM, 2 also exhibits obvious luminescence quenching effect for Cr 2 O 7 2− anion with the LOD value of 7.27 μM. This work possesses potential application in detecting VB 5 in newborn calf serum and Cr 2 O 7 2− in river water samples. [Display omitted] • Four novel uranyl coordination polymers have been synthesized under solvothermal conditions. • Compound 2 is the first luminescent probe to detect VB 5 with "turn-on" sensing method. • Compound 2 also have "turn-off" fluorescence sensing property of Cr 2 O 7 2−. • The mechanisms of 2 sensing VB 5 and Cr 2 O 7 2–are discussed in detail. [ABSTRACT FROM AUTHOR]