Comparative Study on the Effect of NaBr on the Interaction Between Alkyltrimethylammonium Bromide and β-Cyclodextrin

The effect of NaBr on the interaction between alkyltrimethylammonium bromide (CnTAB (n = 14 for TTAB and 16 for CTAB)) and s-CD was studied by surface tension method. The first decrease in the γcmc of TTAB/s-CD in the presence of NaBr mainly due to the elongated effective chain length of the hydrophobic part of the TTAB/s-CD complexes; while the increase in the γcmc of both of the TTAB/s-CD and CTAB/s-CD in the presence of NaBr could be attributed to the close pack of CnTAB at the air/water interface.