Dansyl driven fluorescence paper-based quencher probe for Pr3+ and I- based on calix[4]arene

We have introduced a novel luminous molecular receptor C4DS based on calix[4]arene conjugate bearing dansyl fluorophore with hydrazine carbonyl linkage and characterized it by different spectroscopic methods. This chemosensor has been addressed by fluorescence technique for recognizing two ions, viz., Pr3+ and I-. C4DS demonstrates a minimum detection limit of 3.571 nM for Pr3+ and 2.439 nM for I-. The C4DS sensor has a working concentration range of 0-120 nM for I- and 0-135 nM for Pr3+ with a binding constant of 6.698 x 108 M-1 (Pr3+) and 7.377 x 108 M-1 (I-). We report an easy-to-use, cheap, disposable, paper-based, fluorescent wax printing device for the rapid chemical screening of Pr3+ and I-. The GAUSSIAN 09 software package has been used to optimize C4DS and complex of C4DS and Pr3+ and I- through B3LYP exchange-correlation functional by the basis set LANL2DZ and also intended time-dependent DFT (TDDFT) calculations for supported the fluorescence quenching mechanisms of complexes. The molecular docking inspection has been supported out by using human serum albumin protein structures (2xsi, 2xvq, 2xvu, 2xvv, 2xvw, 2xw0, and 2xw1) with C4DS and molecular docking score has been calculated using HEX software. To assess its analytical applicability, the prepared sensor was effectively used for the determination of two different real samples (for the determination of Pr3+ and I- from two different samples) for the validation with 95-99% recovery of recognized ions.