Calix[4]arene based dipodal receptor nanohybrids for selective determination of chloride ions in aqueous media

A chemical sensor based on p-tert butyl calix[4]arene has been synthesized and characterized using an assortment of spectroscopic techniques such as 1H NMR, 13C NMR, and elemental analysis. For sensor application, organic nanoparticles (N1) of 1 have been primed by implementing re-precipitation technique, which were further employed for preparing organic-inorganic hybrid (H1) by decorating N1 with gold nanoparticles. Both N1 and H1 were characterized using UV–visible, fluorescence, and DLS studies. Photo-physical changes due to anion binding with H1 were scrutinized using UV–visible absorption spectrometer and found it to promptly and selectively recognize Cl− ions in aqueous media. Thus, H1 can be effectively used for recognition of Cl− ions in aqueous media over a wide pH range, in samples of real time importance with a detection limit of 2.84×10−9M with a linear detection range up to 50μM.