Automatic multiple photodegradation unit on a multipumping flow system: Monitoring of ketoprofen

The main objective of this work was the development of a clean methodology involving the use of the multipumping flow concept for the determination of ketoprofen, a non-steroidal anti-inflammatory drug (NSAID), in pharmaceutical samples, thus providing the pharmaceutical industry with an environmental friendly, rapid and low cost method for the chemical control of commercial formulations and an expeditious alternative to the commonly used chromatographic methods. re element of the proposed work is the implementation of a multiple photodegradation unit that was applied to ketoprofen monitoring through fluorometric detection (λex = 330 nm; λem = 401 nm) of the photodegradation product obtained upon UV irradiation. The photodegradation was performed in a methanol/nitric acid medium, being these the only reagents used in the method. A linear working response range for ketoprofen concentrations of up to 50 mg L−1 was obtained, with a correlation coefficient of 0.9997. The detection limit was about 1.45 mg L−1. The results obtained for the determination of ketoprofen in commercial pharmaceutical formulations by the proposed flow procedure, when compared to those furnished by the HPLC reference procedure revealed a good agreement, with relative deviations comprised between −3.1 and 2.2%.