Comparative study of β-cyclodextrin, γ-cyclodextrin and 4--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--butylcalix[8]arene (-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 (7.0×10-1×10, 5.0×10-1×10and 8.0×10-1.0×10 M, respectively), with detection limits of 2.2×10, 1.5×10 and 2.42×10 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 -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.