Multicommutated flow system for the chemiluminometric determination of clomipramine in pharmaceutical preparations

A continuous flow methodology for the chemiluminometric determination of clomipramine in pharmaceutical preparations is described. Clomipramine acts as a sensitizer on the chemiluminescent oxidation of sulphite by Ce(IV). The developed procedure is based on the multicommutated flow concept whose versatility was fully exploited by using a single solution propelling device for the insertion of multiple solutions in propulsion mode. The utilisation of a binary sampling approach enabled sample/reagent mixing within the flow cell with a significant reagent saving. A time-based sample insertion assured an effective control of sample dispersion, enabling the attainment of distinct working concentration ranges by means of the selection of appropriate sampling times. Linear calibration plots were obtained for clomipramine hydrochloride concentrations ranging 2.5–60 mg l^-1, depending on sampling time, with good reproducibility and R.S.D. lower than 4.6% (n = 4). The developed methodology was applied in the analysis of pharmaceutical preparations and the obtained results were in good agreement with those furnished by the reference procedure with R.D. lower than 3.3% and a sampling rate between 19 and 32 samples per hour.