Quenching of pyrene fluorescence by three pyridiniums, pyridine hydrochloride (HP+), N-benzylpyridinium chloride (BP+), and benzylviologen (BV2+), in aqueous solution is enhanced by the introduction of sodium laurylsulfonate (SLS), and the order of the sensitivity of quenching constant to SLS concentration is BV2+ > BP+ > HP+. Conductance experiments indicate no aggregation is formed in the concerned systems. It is concluded that the coiling of the alkyl chain in SLS mol. and the electrostatic interaction between the anionic polar head of SLS mol. and the cationic pyridinium are the causes of the quenching enhancement.

Key words: PYRIDINE P, ANIONIC SURFACTANTS, PYRENE, BENZYL VIOLOGEN, HYDROCHLOTIDE, BENZYL-PYRIDINE