Abstract
In this study, two microextraction methods, viz. continuous‐flow microextraction (CFME) and static liquid‐phase microextraction (s‐LPME), were optimized and compared for the determination of p‐toluidine in water and Chlamydomonas reinhardtii samples. The calibration curve for p‐toluidine was linear in the concentration range of 0.01–5 μg/mL, and the squared regression coefficients (r^2^) for the lines were up to 0.999 for both CFME and s‐LPME treatments. Detection limits in CFME and s‐LPME were 8.2 ng/mL and 4.9 ng/mL, based on a signal‐to‐noise (S/N) ratio of 3, respectively. The precision was tested, in five replicates, by analysis of a 100‐ng/mL standard solution of p‐toluidine and the relative standard deviations were 5.43 and 3.08% for CFME and s‐LPME, respectively. The concentration factors were 5.5 and 14.4 for CFME and s‐LPME, respectively. s‐LPME has a higher extraction efficiency, lower detection limit, and higher concentration factor than that of CFME. Additionally, the s‐LPME method is precise and reproducible, and requires only a 3.0‐μL microdrop of extraction solvent. Therefore, this procedure is more convenient in use, and viable for qualitative and quantitative analysis of p‐toluidine in water and biota samples.