Basalt fibers grafted with a poly(ionic liquids) coating for in-tube solid-phase microextraction.

To improve the durability and extraction efficiency of an ionic liquid coating, 1-dodecyl-3-vinylimidazolium bromide was polymerized and grafted onto basalt fibers for in-tube solid-phase microextraction. To develop an extraction tube, basalt fibers grafted with the poly(ionic liquids) coating were filled into a polyether ether ketone tube with a 0.75 mm inner diameter. The extraction tube was connected to high-performance liquid chromatography system equipped with a sampling pump to build an online enrichment and analysis system. Using four common phthalates as model analytes, the extraction tube was investigated by the online analysis system. Good enrichment performance was exhibited by high enrichment factors ranging from 851 to 1858. Under the optimum conditions, an online analysis method was established, and good linearity (0.03-12 and 0.15-12 μg/L) and low limits of detection (0.01-0.05 μg/L) were achieved. This analysis method was applied to real samples including water in a disposable plastic box and the bottled water, some targets were detected but not quantified, and the relative recoveries spiked at 2, 5 and 10 μg/L were in the range of 86.4-119.5%.