Satisfactory determination of several kinds of pesticide in edible oils is an important but not a new problem. In actual fact the quantitative determination of chemical species or real matrices that are scarcely soluble or completely insoluble in aqueous solutions has always posed a serious problem in chemical analysis and has only been partially solved by such techniques as gas chromatography, which are more suitable when employed in a laboratory than in situ. A substantial contribution to solving this problem was the development of organic phase enzyme electrodes (OPEEs), i.e. enzymatic electrodes capable of operating in organic solvents [1-3] and that can also act in situ. One classical example is that of inhibition OPEEs to analyse different types of pesticides that are relatively insoluble in aqueous solution, in the development of which also our team was recently involved [4-6]. The draw-back consists of the fact that it is often complained that inhibition biosensors are relatively unselective versus the pesticides belonging to different phytopharmaceutical classes. Immunosensors, on the contrary, are the most selective biosensors, and our team has in recent years fabricated several immunosensors [7-10], including also devices for pesticide determination [11], albeit operating only in aqueous solution. However, we recently developed a new organic phase immuno-electrode (OPIE) [12]. Using this new device, applications were developed to detect triazinic pesticides in extra-virgin olive oil, obtaining good results [12]. Therefore, new applications were recently developed using the novel OPIE to detect several herbicides and pesticides in sunflower oil.
展开▼
