Development of a photochemically induced fluorescence-based optosensor for the determination of imidacloprid in peppers and environmental waters

• Published in: Talanta (Oxford) 2007-05, Vol.72 (3), p.991-997
• Main Authors: LOPEZ FLORES, J, DIAZ, A. Molina, FERNANDEZ DE CORDOVA, M. L
• Format: Article
• Language: English
• Subjects: Analytical chemistry; Applied sciences; Chemistry; Chromatographic methods and physical methods associated with chromatography; Exact sciences and technology; General, instrumentation; Global environmental pollution; Imidacloprid; Optosensor; Other chromatographic methods; Peppers; Photochemically induced fluorescence; Pollution; Spectrometric and optical methods; Water
• ISSN: 0039-9140; 1873-3573
• DOI: 10.1016/j.talanta.2006.12.024

A novel flow-through solid phase spectroscopic assembly implemented with photochemically induced fluorescence (PIF) has been developed for the rapid, sensitive and selective determination of imidacloprid. The pesticide is derivatized on-line by irradiation with ultraviolet light providing an intensively fluorescent compound. The determination is carried out by measuring the fluorescence intensity of the photoproduct once retained on C 18 silica gel filling the flow-cell. The method proposed has been applied to the determination of imidacloprid in natural waters and peppers. The quantification limit (QL) (0.015 mg kg −1) in peppers was lower than the maximum residue limit (MRL) established by Spanish Legislation (0.5 mg kg −1). The method also seems to be suitable for environmental water analysis providing satisfactory recoveries (94.0–108.6%). The results obtained in the analysis of real samples are in good agreement with those provided by a reference liquid chromatography (HPLC) method.