Determination of The Release Rate Profiles of Aldicarb and Cadusafos as Alginate Controlled-Release Formulations Released in Water by Using Newly Modified ColorimetricMethods

摘要

Cadusafos and aldicarb released from the alginate controlled release formulations and granule formulations in static water were determined using new colorimetric methods. These methods are sensitive and can be applied for the determination of levels as low as 0.02 ppm (20ppp) released in water. The active agents from commercial granule formulation of cadusafos (15G) and aldicarb (10G) were released faster into water than that from the corresponding alginate controlled release formulations (CR). After21 days post- application, more than 58.72% of aldicarb was released from the granule formulation into water while for cadusafos granule formulation more than 91.56% of the cadusafos active ingredient was determined in solution. On the other hand, the CR. formulations at the same period were released by not more than 3.98% and 13.33% of the originally applied amount of aldicarb and cadusafos, respectively. Aldicarb in calcium alginate beads was released in the following order FA3>FA_6>FA_9. Also, cadusafos release rate was in the same trend (FC_3>FC_6>FC_9). The maximum release rate was achieved by the CR formulation of aldicard and cadusafos after 77days post- application and the range was 40.06% - 51.82% for aldicarb while for cadusafos was 50.64% -65.85%. On the other hand, at the same time the concentrations of both active ingredient released from the commercial formulations was ranged between 0.28% - 0.34% of the original applied amount.