Simple fabrication of a carbaldehyde based fluorescent 'turn-on' probe for the selective and sole detection of Pd2+: application as test strips

摘要

A new fluorescent "turn-on" probe (DHMC) has been designed and synthesized to selectively detect Pd2+ among other cations at physiological pH. Upon incremental addition of Pd2+ into the probe solution, a "turn-on" emission enhancement was noticed with a similar to 69 nm red shift at 562 nm in CH3CN/H2O (4/1, v/v) solution. The limit of detection and binding constant values have been determined and found to be on the order of 7.4 x 10(-8) M and 1.7 x 10(5) M-1 respectively, which clearly suggests that the probe is very efficient in detecting Pd2+ at very minute levels and also the DHMC-Pd2+ complexation is stable enough too. A brilliant application of the probe has been explored which indicates that DHMC can detect Pd2+ in the solid state too. DFT and TDDFT calculations are carried out to interpret the electronic structure and sensing mechanism.