Rapid extraction of BTEX in water and milk samples based on functionalized multi-walled carbon nanotubes by dispersive homogenized-micro-solid phase extraction.

Abstract

An advanced synthesis based on the phenylalanine (Phe) and task-specific ionic liquid (TSIL) functionalized on multi-walled carbon nanotubes (Phe/TSIL@MWCNTs), was used to extract benzene, ethylbenzene, toluene, and xylene (BTEX) from cow's milk, powdered milk, and farm water samples. The BTEX was efficiently extracted by ultrasound-assisted dispersive homogenized-micro-solid phase extraction (USA-DH-µ-SPE) between 95.1% and 103.4%. By procedure, 50mg of Phe/TSIL@MWCNTs was added to 0.2mL of acetone and injected into 10mL of the samples. The upper aqueous solution was vacuumed, the vial heated to 80°C, and the BTEX desorbed in the vial. Then, using a Hamilton syringe, 1-20µL of gas in the headspace vial was determined by injecting it into the gas chromatography with flame ionization detection (GC-FID). The linear range, LOD, and LOQ for BTEX in milk and water samples were obtained at 0.05-500µg L-1, 15ng L-1, and 50ng L-1, respectively (r=0.9997, RSD%=2.27).