Abstract
The supramolecular interaction of nizatidine (NIZ) and beta -cyclodextrin ( beta -CD) has been studied by spectrofluorimetry. The results showed that beta -CD reacted with NIZ to form an inclusion complex. The NIZ- beta -CD complex formed a host-guest complex in 1:1 stoichiometryand inclusion constant (K = 3.15 x 10 super(2) L mol super(-1)) and was ascertained by the typical double reciprocal plots. Furthermore, the thermodynamic parameters ( Delta H[degrees], AS[degrees] and Delta G[degrees]) associated with the inclusion process were also determined. Based on the significant enhancement of the fluorescence intensity of NIZ produced through complex fonnation, a simple, accurate, rapid and highly sensitive spectrofluorometric method for the detennination of NIZ in aqueous solution in the presence of beta -CD was developed. The measurement of relative fluorescence intensity was earned with excitation at 314 nm. The factors affecting the inclusion complex formation were studied and optimized. Under the optimum reaction conditions, linear relationships with good conelation coefficients (0.999) were in the concentration range of 0.04-O.1 mu g mL for spectrofluorimetry. The limit of detection (LOD) was found to bel.27x10 super(-3) mu gmL super(-1). The proposed method was successfully applied to the analysis of NIZ phannaceutical dosage formulations with good accuracy; the recovery percentages ranged from 95.4-106.85%.