Study of α-, β- and γ-Cyclodextrin complexes with Cetirizine by UV Spectroscopy and Isothermal Titration Calorimetry

摘要

Complex formation between the antihistaminic drug Cetirizine (CTZ) and α-, β- and γ-cyclodextrin (CD) was investigated by UV spectroscopy and Isothermal Titration Calorimetry (ITC). UV spectroscopy demonstrated that CTZ forms more stable complexes with β-CD (Ka=5641±358 M-1) than α-CD (Ka=1434 ±60 M-1). No information could be extracted from the UV spectroscopic analysis of CTZ γ-CD complex. ITC results for association constant determination were in compliance with UV results and confirmed that CTZ-β-CD has the highest association constant (2540 ± 122 M-1). The association constants from ITC measurements for CTZ-γ- CD and CTZ-α-CD were found to be 1200±50 M-1 and 800 ±22 M-1, respectively.