Determination of Trace Levels of Irgarol in Estuarine Water Matrices by Bar Adsorptive Microextraction

Bar adsorptive microextraction (BAµE), using selective sorbent phases, followed by liquid desorption in combination with large volume injection-gas chromatography coupled to mass spectrometry (BAµE-LD/LVI-GC-MS), is proposed for the determination of trace levels of irgarol in estuarine water matrices. While we compared several polymers and activated carbons, one of the latter coatings showed much higher selectivity through BAµE. Assays performed on 25 mL of ultra-pure water sample fortified at 0.6 µg/L levels of irgarol yielded recoveries of 74.5 ± 8.6%, under optimized experimental conditions. The proposed analytical procedure showed convenient detection limits (16.0 ng/L) and good linear dynamic range (0.2-16.0 µg/L), with determination coefficients of 0.9982. Good precision was also achieved with RSD lower than 12.0%. The application of the present analytical approach on estuarine water samples by using the standard addition methodology revealed good sensitivity and linearity. The proposed methodology, using nanostructured sorbents and operating under the floating sampling technology, proved to be a suitable analytical alternative to monitor irgarol in estuarine water matrices. Moreover, it is easy to implement, reliable, sensitive, require low sample volume and have the possibility to choose the most selective sorbent coating according to the target compound involved.