Comparative study of β-cyclodextrin, γ-cyclodextrin and 4-tert-butylcalix[8]arene ionophores as electroactive materials for the construction of new sensors for trazodone based on host-guest recognition

BACKGROUND: Trazodone (TRZ) is a second-generation non-tricyclic antidepressant derived from a triazolopyridine derivative, which is mainly used to treat emotional disorders and conditions related to depressive disorders. PURPOSE: This study investigated the design, development and characteristics of polyvinyl chloride (PVC) membrane sensors for trazodone HCl (TRZ). METHODS: The developed sensing membranes were constructed using β-cyclodextrin (β-CD; sensor 1), γ-cyclodextrin (γ-CD; sensor 2) or 4-tert-butylcalix[8]arene (t-BC8; sensor 3) ionophores as sensing materials in addition to ionic sites and dioctyl phthalate in the PVC matrix. RESULTS: Sensors 1, 2 and 3 displayed fast, stable and near-Nernstian response over a relatively wide trazodone concentration range (7.0×10(−6)–1×10(−3), 5.0×10(−5)–1×10(−3)and 8.0×10(−6)–1.0×10(−3) M, respectively), with detection limits of 2.2×10(−6), 1.5×10(−5) and 2.42×10(−6) M, respectively in the pH range of 3.0–6.0. The sensors demonstrated good selectivity for TRZ in the presence of different ionic compounds. The accuracy and precision of the proposed sensors were assessed by the determination of 40.7 μg/ml of TRZ, which showed average recoveries of 99.6%, 99.1% and 98.5% with mean relative standard deviations of 2.4%, 2.5% and 2.6% for sensor 1, 2 and 3 respectively. Molecular modeling was used to calculate the host-guest binding energy. The lowest free binding energy was −6.243, −5.752 and −5.7105 kcal/mol for 1:1 stoichiometry host-guest complexes of trazodone and β-CD, γ-CD and t-BC8, respectively, which was in-line with a Nernstian response. CONCLUSION: The investigated methods can be applied for the determination of TRZ in pharmaceutical preparations. The results of investigated dosage-form of TRZ show good agreement with those using the US Pharmacopeia method.