In order to perform UV–Vis spectrophotometry for the determination
of carbendazim, maximum absorption wavelength was
established. In the preliminary experiment, the sample solution
containing different concentrations of carbendazim was examined
according to the recommended procedure for DLLME and the
corresponding spectra of sedimented phase was recorded in the
range of 500–850 nm. The absorption spectra are shown in Fig. 3.
The results showed that maximum absorption occurs at 685 nm
for the sedimanted phase and the absorbance at this wavelength is
increased upon increasing of carbendazim concentration. Therefore,
685 nm was selected for measuring the absorbance of the
extracted phase throughout this study