Cyanide and chloroform detection through J-aggregates based aggregation induced emission probe with real sample applications

Abstract

Isopthalamide based probe DPI has been synthesized by an easy two-step substitution reaction. Unique fluorescence properties of probe DPI were exploited for sensing of CNˉ and chloroform. Various spectroscopic techniques such as NMR, LC-MS, SEM, DLS, UV-Vis. and fluorescence spectroscopy in combination with DFT studies were used to confirm efficient detection of CN‾ through a non-covalent interaction of cyanide with probe. Furthermore, probe showed fluorescence emission at 360 nm which shifted significantly to 415 nm upon addition of water exhibiting unique AIE characteristics and formation of desired J-aggregates. Mechanistically, CN‾ and chloroform were selectively detected through fluorescence quenching with 9 nM and 0.2 % v/v limit of detection (LOD), respectively. Photoinduced electron transfer (PET) was proven to be involved as a sensing mechanism. Moreover, DPI exhibited interesting solvatochromism properties. DPI was proven to be a highly sensitive probe which showed solid-state and vapor phase on-field detection of CN‾. Similar sensing behavior of DPI probe towards CN‾ was seen in food and water samples.