Fluorescence quenching of 2-aminofluorene by cetylpyridinium chloride, iodide ion and acrylamide in non-ionic micelles: Tweens

The fluorescence quenching of 2-aminofluorene by cetylpyridinium chloride ( CPy), iodide ion (I-) and acrylamide (AC) has been studied in different con centrations of Tween-20, Tween-40, Tween-60 and Tween-80 surfactants, The r esults show that CPy and I- ion bind as well as get partitioned, whereas AC only gets partitioned. The high values of binding constants for CPy in com parison to I- ion are due to the long hydrocarbon chain length. The binding and partitioning coefficients of CPy increase, whereas those of I- ion dec rease with the increase in the Tween number. The values of partitioning coe fficient of AC also decrease with increase in the Tween number. On the othe r hand, quenching rate constants for each quencher in each Tween decrease i n going from Tween-20 to Tween-80. (C) 1999 Elsevier Science S.A. All right s reserved.