A sensitive fluorescence probe for DDT-type pesticides Original Research Article

Nile red was examined as a possible fluorescence probe for DDT-type contaminations in aqueous solutions. The effects of such a pesticide (i.e. methoxychlor) on Nile red fluorescence properties was shown to be strong enough for analytical purposes. Several spectral effects were observed: these include a selective complexation reaction, resulting in a new fluorescence peak (at 605 nm) and a polarization enhancement of the original Nile red peak (at 663 nm). In addition, a linearly dependent blue-shift of the original Nile red fluorescence was obtained. The fluorescence enhancement and intensity of the new complex peak were linearly dependent on pesticide concentration in the μg ml−1 range. The probe showed a certain selectivity to DDT-type pesticides.