Response surface methodology for the optimization of dispersive liquid-liquid microextraction of chloropropanols in human plasma

Chloropropanols are processing toxicants with a potential risk to human health due to the increased intake of processed foods. A rapid and efficient method for the determination of three chloropropanols in human plasma was developed using ultrasound-assisted dispersive liquid-liquid microextraction. The method involved derivatization and extraction in one step followed by gas chromatography with tandem mass spectrometry analysis. Parameters affecting extraction, such as sample pH, ionic strength, type and volume of dispersive and extraction solvents were optimized by response surface methodology using a pentagonal design. The linear range of the method was 5-200 ng/mL for 1,3-dichloro-2-propanol, 10-200 ng/mL for 2,3-dichloro-2-propanol and 10-400 ng/mL for 3-chloropropane-1,2-diol with the determination coefficients between 0.9989 and 0.9997. The limits of detection were in the range of 0.3-3.2 ng/mL. The precision varied from 1.9 to 10% relative standard deviation (n = 9). The recovery of the method was between 91 and 101%. Advantages such as low consumption of organic solvents and short time of analysis make the method suitable for the biomonitoring of chloropropanols.