Sensitive recognition of cyanide through supramolecularly complexed new calix[4]arenes

摘要

Two new calix[4]arene based fluorescence sensors (L1 and L2) have been synthesized and characterized. L1 was found to selectively quench fluorescence intensity upon addition of Cu~(2+) ions through host-guest complexation and display "on-off" behavior while L2 was not that efficient. The in situ generated LlCu~(2+) complex could further recognize CN~- from the anionic broth with a distinct "off-on" behavior in the fluorescence titration.