Research Article

Three Different Spectrophotometric Methods for Simultaneous Determination of Pyriproxyfen and Chlorothalonil Residues in Cucumber and Cabbage Samples

Table 3

Percentage mean recovery of pyriproxyfen and chlorothalonil in real cucumber samples by proposed methods.

Pyriproxyfen
Fortification level (μg·mL−1)1st and 2nd derivativesRatio spectra derivativeMean centering of ratio spectra
1D281.80 nm2D281.40 nm2D285.60 nm1DD272 nm1DD286 nm278 nm
%R%RSD%R%RSD%R%RSD%R%RSD%R%RSD%R%RSD

3.088.323.8386.854.5988.504.0388.064.9589.283.6288.004.56
20.094.722.7893.412.7394.163.1394.403.1995.242.4893.872.17
30.096.272.1896.422.2094.862.4494.732.3296.391.9295.142.15

Chlorothalonil
Fortification level (μg·mL−1)1st and 2nd derivativesRatio spectra derivativeMean centering of ratio spectra
1D329.20 nm2D262.60 nm2D266 nm1DD228 nm1DD262 nm254 nm
%R%RSD%R%RSD%R%RSD%R%RSD%R%RSD%R%RSD

1.090.474.3888.044.8182.245.1181.515.4590.324.6387.374.43
4.095.392.1994.843.4194.063.0991.324.4395.302.7095.933.10
7.097.042.2495.153.7695.882.1091.363.1796.852.2396.443.00