Fluorescence quenching of 8-methyl quinolinium: An efficient halide indicator mechanism

Abstract Fluorescence quenching of 8-methyl quinoline in acidified aqueous solution by various halides (Cl −, Br −, I −) is studied using steady state and time resolved fluorescence techniques. The quenching process is characterized by Stern–Volmer (S–V) plots. It is found that the mechanism of quenching is dynamic in nature and occurs through photo-induced electron transfer. Having considerably higher quenching constant, much longer fluorescence lifetime (~ 42 ns), mono-exponential fluorescence decay and commercial availability project this molecule as a potential candidate for practical applications.