Fluorescent sensitive detection of luteolin in Chrysanthemum tea using boric acid functionalized binuclear Zn-Eu-MOFs

Owing to Zn 2+ -sensitized fluorescent effect, boric acid functionalized zinc-europium binuclear metal-organic frameworks ( Zn-Eu-MOFs ) are synthesized and applied in fluorescent quenching detection of luteolin in Chrysanthemum tea for the first time. Eu 3+ /Zn 2+ and 5-boronobenzene-1,3-dicarboxylic acid (BBDC) are utilized via a fast one-pot microwave process at 120 °C for 1 h. Due to energy transfer efficiency change by “antenna” effect and better effective energy transfer of Zn 2+ than Eu 3+ , Zn 2+ increases fluorescence of Zn-Eu-MOFs nearly 3.5 times. Different ligands and different metal ions are compared to synthesize Zn-Eu-MOFs . Highly specific binding affinity of boric acid towards cis-diol structure in luteolin and chelating of Zn 2+ with luteolin achieves fluorescent quenching detection of luteolin with low limit of detection of 16 nΜ and high selectivity. When it is utilized in fluorescent detection of luteolin in water and Chrysanthemum tea, mean recoveries are obtained from 99.5 % to 102.7 % and from 99.3 % to 100.6 %, respectively.