Improved Determination of Dichloroacetic and Trichloroacetic Acids in Water by Solid Phase Extraction Followed by Ultra-high Performance Liquid Chromatography–Tandem Mass Spectrometry

ABSTRACT

A simple, rapid, and sensitive ultra-high performance liquid chromatography–electrospray ionization tandem mass spectrometry method was developed for the determination of dichloroacetic acid and trichloroacetic acid in water. Analytes were extracted and concentrated by solid phase extraction. Under the optimized conditions, the extraction recoveries ranged from 98.13 to 100.57% for both analytes. The separation was performed on a reversed phase C18 column by using gradient elution. Detection was performed in multiple reaction monitoring mode using negative electrospray ionization. The developed method yielded limits of detection from 0.04 to 0.08 ng/mL. The intra-day and inter-day precisions for the analytes were less than 4% and the accuracy was between 99.12 and 102.38%. To the best of our knowledge, this work describes for the first use of solid phase extraction with ultra-high performance liquid chromatography tandem mass spectrometry for dichloroacetic acid and trichloroacetic acid in water.

KEYWORDS:

• Disinfection by-products
• solid phase extraction
• ultra-high performance liquid chromatography–tandem mass spectrometry
• water analysis