All-Solid-State Citalopram Sensor and its Application for the Analysis of Pharmaceutical Formulations

Citalopram (CP), which is a selective serotonin reuptake inhibitor (SSRI), is used for the treatment depression. Due to the importance of the analysis of this compound, an all-solid-state polymeric membrane electrode (ASS-PME) has been devised using an ion-pair agent as the sensing element of the device. The experimental results proved that the best sensor response is observed using membranes including 7%wt CP-tetraphenyl borate (the sensing element), 57%wt dibutyl phthalate as the solvent mediator, 33%wt poly(vinyl chloride) and 3%wt of an ionic liquid. The ASS element of the device is a conductive composite of graphite, multiwall carbon nanotubes (MWCNTs), and epoxy resin which is coated on a Cu wire, which is finally coated with a thin film of the PME. The response of the ASS-PME was linear in the range of 1.0×10-7 to 1.0×10-3 mol L-1 and reached the slope of 57.3±0.3 mV/decade under optimal conditions. The experiments revealed that the optimized Citalopram ASS-PME is applicable in the quality control analyses, which was validated by its application for measurement of Citalopram in its tablets.