Anion recognition properties of chromone-based organic and organic–inorganic hybrid nanoparticles

Abstract

An organic compound 1 based on a chromone fluorophore was synthesized and processed into organic nanoparticles (ONPs) N1 through a reprecipitation method. The photophysical properties of the organic nanoparticles were evaluated through UV-vis absorption spectroscopy, and these ONPs selectively recognize cyanide ions in an aqueous medium. Further, these organic nanoparticles are used as a platform for gold nanoparticles thus forming a hybrid assembly H1 of organic and gold nanoparticles. The sensing property of this resultant hybrid assembly was also evaluated through UV-vis absorption spectroscopy, and the system has shown selectivity for hydrogen sulphate in an aqueous medium. Furthermore, titration with cyanide and hydrogen sulphate are performed in order to estimate the lowest detection limit of cyanide and hydrogen sulphate, and it showed that cyanide and hydrogen sulphate can be detected at the lowest limit of 9.4 μM and 46.63 μM, respectively. Thus, ONPs acted as sensors for cyanide, and ONPs coated with gold nanoparticles have been developed as sensor for hydrogen sulphate in an aqueous medium.