An on-line coupling of nanofibrous extraction with column-switching high performance liquid chromatography - A case study on the determination of bisphenol A in environmental water samples.

Polyamide 6 nanofiber polymers were used as modern sorbents for on-line solid phase extraction (SPE) coupled with liquid chromatography. The on-line SPE system was tested for the determination of bisphenol A in river water samples. Polyamide nanofibers were prepared using needleless electrospinning, inserted into a mini-column cartridge (5 × 4.6mm) and coupled with HPLC. The effect of column packing and the amount of polyamide 6 on extraction efficiency was tested and the packing process was optimized. The proposed method was performed using a 50-µL sample injection followed by an on-line nanofibrous extraction procedure. The influence of the washing mobile phase on the retention of bisphenol A during the extraction procedure was evaluated. Ascentis Express C18 (10cm × 4.6mm) core-shell column was used as an analytical column. Fluorescence detection wavelengths (λ = 225nm and λ = 320nm) were used for identification and quantification of Bisphenol A in river waters. The linearity was tested in the range from 2 to 500µgL (using nine calibration points). The limits of detection and quantification were 0.6 and 2µgL, respectively. The developed method was successfully used for the determination of bisphenol A in various samples of river waters in the Czech Republic (The Ohře, Labe, Nisa, Úpa, and Opava Rivers).