Determination of Pindone in Baits by using Time-Resolved Lanthanide-Sensitized Luminescence and Kinetic Methodology

A simple and fast kinetic method for the determination of pindone in baits was developed. It is based on the inhibitory effect of this indanedione rodenticide on the luminescence of the europium(III)-thenoyltrifluoracetone system in the presence of cetyltrimethylammonium bromide. The relatively long lifetime of this system allows the time-resolved mode to be used, which eliminates any fluorescence signal. To avoid the potential static background signal of the sample, the difference between the initial rate obtained in the absence and presence of pindone is used as the analytical parameter, which is obtained within only 0.2 s with the aid of a stopped-flow mixing technique. The calibration graph is linear in the range 0.1-10.0 μg ml −1 pindone and the detection limit is 0.04 μg ml −1 . The relative standard deviation is close to 3%. The recoveries obtained by applying the method directly to the analysis of bait samples ranged from 92.0 to 114%.