Simultaneous determination of triclosan, triclocarban, triclocarban metabolites and byproducts in urine and serum by ultra-high-performance liquid chromatography/electrospray ionization tandem mass spectrometry

Abstract

Rationale: Triclosan (TCS) and triclocarban (TCC) are ubiquitous antimicrobial agents incorporated in consumer and personal care products. Due to their human health risks, it is essential to develop a sensitive and accurate analytical method to simultaneously quantify TCS, TCC, as well as their metabolites and byproducts in urine and serum samples.

Methods: The quantitative parameters of TCS, TCC, TCC metabolites and byproducts (2'-OH-TCC, 3'-OH-TCC, 6-OH-TCC, DHC, DCC, NCC) were optimized by using ultra-high-performance liquid chromatography/electrospray ionization tandem mass spectrometry (UHPLC/ESI-MS/MS). Enzymatic hydrolysis of the samples was optimized based on enzyme dosage and incubation time. The efficiencies of solid-phase extraction (SPE) and liquid-liquid extraction (LLE) were compared. The effectiveness of the established method was evaluated, and method application was validated using real urine and serum samples.

Results: The conjugates were sufficiently hydrolyzed under 500 U/mL β-glucuronidase and 80 U/mL sulfatase at 37°C for 4 h. Compared with the LLE method, SPE achieved higher extraction efficiency in both urine and serum samples. The optimized SPE-UHPLC/ESI-MS/MS method showed low limits of detection (LODs) in the range 0.001-0.3 ng/mL and good linearity (R² > 0.99) at 0.01-150 ng/mL in both matrices. Excellent recoveries of 82.0%-120.7% (urine) and 76.7%-113.9% (serum) were obtained with low relative standard deviation (RSD, <7.6%) for inter-day and intra-day injections. This method was applicable to quantify target compounds in multiple biological urine and serum samples. Notably, TCS and TCC were detected with average concentrations of 8.37 and 10.46 ng/mL, respectively, in 15 Chinese female urine samples, with the simultaneous detection of TCC metabolites and byproducts.

Conclusions: A reliable method was established to simultaneously determine TCS, TCC, TCC metabolites and byproducts in urine and serum samples by using UHPLC/ESI-MS/MS. This sensitive methodology provides the basis for the evaluation of TCS and TCC exposure at the metabolic level.