Simultaneous Flow-Injection Solid-Phase Fluorometric Determination of Thiabendazole and Metsulfuron Methyl Using Photochemical Derivatization

Abstract

A flow-through optosensor implemented with photochemically induced fluorescence (PIF) is reported for the simultaneous determination of thiabendazole (TBZ) and metsulfuron methyl (MET). TBZ is determined by measuring its native fluorescence once retained on the solid support filling the flow-cell of a FI-system. On the other hand, a strongly fluorescent photoproduct from MET is generated on-line in micellar medium by UV irradiation and monitored in a similar way to TBZ. MET photoproduct and TBZ are separated by placing in the flow-system a minicolumn, filled with C18 silica gel, which allows their sequential arrival to the detection area. The sorption of the species on the solid support in the detection area provides a noticeable improvement in sensitivity and selectivity when comparing with their determination in homogeneous solution. The detection limits and RSDs for TBZ and MET are 2.5 and 3.3 ng ml -1 and 1.1 and 2.4%, respectively. The method is successfully applied to environmental water samples.

Luminescence Sensors Applied to Water Analysis of Organic Pollutants—An Update

“…A flow-through optosensor implemented with a PIF was reported for the simultaneous determination of the fungicide thiabendazole and the herbicide metsulfuron methyl in environmental waters [76]. Samples containing the pesticides in a micellar medium (sodium dodecyl sulfate) are injected in the carrier stream and flow through the photoreactor, where the UV light promotes the photodegradation of the herbicide into a fluorescent photoproduct, while thiabendazole does not suffer any significant degradation.…”

Review of Characteristics and Analytical Methods for Determination of Thiabendazole

“…Two years later, López Flores et al [73] developed a flow-through optosensor for determining TBZ and metsulfuron methyl in water samples. As a solid support, the authors used C 18 silica gel placed in the flow cell.…”

Recent trends in solid phase spectrometry: 2003–2009. A Review

“…Although implementations of the FI-SPS system with photochemically induced fluorescence are reported [23][24][25][26][27], the light measurement systems are not specialized.…”

“…Many FI-SPS methods have been reported for the analysis of pesticides [25,85,[92][93][94][95]. To increase the selectivity, the stepwise elution method was employed as mentioned above.…”