Rapid single-step pretreatment of urine samples using a 2D carbon microfiber fractionation for phthalate and metabolite detection via GC–MS and LC-MS/MS

Phthalates (PAEs) are widely used as plasticizers and softeners. PAEs and their metabolites (PMs) are considered toxic substances, causing endocrine disruption and damage to reproductive and immune systems. Due to their different polarities, a comprehensive analysis of PAEs and PMs in real samples requires multi-step, complex, and expensive pretreatments, increasing the possibility of sample contamination or analyte losses. In this work, a fast and eco-sustainable sample pretreatment method that allows PAEs and PMs analysis in urine samples by using a two-dimensional microscale micro-carbon fiber (CF) / active micro-carbon fiber (ACF) (2DµCFs) device is proposed. 2DµCFs device allows PAEs, PMs, and water-soluble impurities separation in a single pretreatment exploiting the selective adsorption of CFs and ACFs that is carried out by using small solvent amounts. Furthermore, the 2DµCFs device reduces the matrix effect allowing reliable GC–MS and LC-MS/MS analyses. Limits of quantification were in the range of 15–25 ng mL-1 and of 20–30 ng mL-1, and recoveries were in the range of 78.1 %-87.1 % and 79.4 %-97.3 %, for PAEs and PMs, respectively. The method also showed good reproducibility, with relative standard deviations in the range of 3.8 %-13.3 % and 3.3 %-11.3 % for PAEs and PMs, respectively. Considering these results, the 2DµCFs sample pretreatment procedure can be considered a powerful tool for effective, fast, accurate, and eco-sustainable PAEs and PMs analyses in real samples.