Development of an immunosensor based on the measurement of fluorescence

Consumers concern about the presence of pesticides in food is increasing. However current techniques for detecting pesticide residues in olive oil are very expensive and slow, which make them difficult to apply in commercial conditions. For this reason, the Instituto Valenciano de Investigaciones Agrarias (IVIA) and Universidad Politécnica de Valencia (UPV) have decided to develop an immunosensor as an alternative, fast and cheap method to measure the concentration of some pesticides in olive oil. This work shows the developed transducer by IVIA based on a photovoltaic sensor that transforms the fluorescent radiation to an electrical signal. The immunosensor is based on an immunologic reaction which causes fluorescence on the sample. The intensity of the fluorescence is related with the concentration of marked antibodies. The performed tests with two types of immunoassays and fluorescent markers (FITC and ELF97) have demonstrated the robustness and reliability of the developed transducer. The immunosensor is able to discriminate different concentrations of marked antibodies. This study has demonstrated the possibility of applying this immunosensor to detect chemical residues from pesticide treatments in olive oil samples. These results validate the sensor for future commercial applications.