Chemiluminometric photo-induced determination of Strychnine in a Multicommutation flow assembly

This paper deals on the determination of Strychnine, a potent and dangerous pesticide and the analytical procedure is based on the photo-induced chemiluminescence of the pesticide by means of the Multicommutation continuous-flow methodology. Small segments of the pesticide solution were sequentially alternated with segments of the solution for adjusting the suitable medium for the photodegradation. The required time of UV irradiation was obtained by stopped-flow during 150s; then, the resulting solution formed alternated segments with the oxidizing solution containing 5x10(-3)moll(-1) Ce(IV) in 0.6moll(-1) nitric acid. The calibration range, from 2mugl(-1) to 50mgl(-1), resulted in a linear behaviour over the range 25mugl(-1) to 20mgl(-1) and fitting the equation: I=4706x+624 with a correlation coefficient of 0.9955. The limit of detection was 2mugl(-1) and the sample throughput 15h(-1). After testing the influence of a large series of potential interferents, the method was applied to different kinds of samples.