Abstract :
Screen-printed carbon-based electrodes, operating as working electrodes of the single use commercial three-electrode assemblies, were surface modified with thin films of the condensation polymers of β-cyclodextrin (β-CDP) or carboxymethylated β-cyclodextrin (β-CDPA) in order to fabricate disposable electrochemical sensors for determination of tricyclic antidepressive drugs. The azepine and phenothiazine antidepressive drugs were determined by using a simple two-step procedure developed which comprised a preconcentration step followed by the differential pulse voltammetry quantification. The accumulation properties of the β-CDPA film appeared to be favorable as compared to those of the β-CDP film. Concentration calibration curves were linear within the range from 1.96×10−7 to 2.75×10−6 M for individual drugs after 120 s accumulation. The corresponding detection limits were from 4×10−8 to 5×10−7 M and 1×10−8 to 1.1×10−7 M for the β-CDP and β-CDPA-modified electrodes, respectively. A sensor featuring the β-CDPA film-modified electrode was applied successfully for the antidepressant determination in a model serum.