In this work, the inclusion complex formation between a cationic surfactant, cetyltrimethyl ammonium bromide (CTAB) and β-cyclodextrin was investigated at various temperatures using coated wire ion selective electrodes. Obtained data indicates that inclusion complexes, S(CD) and S(CD)2 have been formed between CTAB and β-CD in aqueous solution. We have used a least mean squares computer fitting program using K1 and K2 as adjustable parameters. Investigation showed that the K1 (first equilibrium constant) for S(CD) formation is greater than K2 (second equilibriumconstant) for S(CD)2 formation. The experiments were carried out at different temperatures. Finally thermodynamic parameters of the complexation, i.e. ΔG°, ΔH° and ΔS° have been also calculated. The thermodynamic parameters showthat the hydrophobic effect has a very important role in complexation process. The large value of ΔG° indicates that complexation between CTAB and β-CD is very favorable.
