Dispersive liquid–liquid microextraction
(DLLME) is an extremely
fast and efficient sample preparation procedure. For its capability
and applicability to be fully exploited, full automation of its operations
seamlessly integrated with analysis is necessary. In this work, for
the first time, fully automated agitation-assisted demulsification
(AAD)-DLLME integrated with gas chromatography/mass spectrometry was
developed for the convenient and efficient determination of polycyclic
aromatic hydrocarbons in environmental water samples. The use of a
commercially available multipurpose autosampler equipped with two
microsyringes of different capacities allowed elimination or significant
reduction of manpower, labor, and time with the large-volume microsyringe
used for liquid transfers and the small-volume microsyringe for extract
collection and injection for analysis. Apart from enhancing accessibility
of DLLME, the procedure was characterized by the application of agitation
after extraction to break up the emulsion (that otherwise would need
centrifugation or a demulsification solvent), further improving overall
operational efficiency and flexibility. Additionally, the application
of low-density solvent as extractant facilitated the easy collection
of extract as the upper layer over water. Some parameters affecting
the automated AAD-DDLME procedure were investigated. Under the optimized
conditions, the procedure provided good linearity (ranging from a
minimum of 0.1–0.5 μg/L to a maximum of 50 μg/L),
low limits of detection (0.010–0.058 μg/L), and good
repeatability of the extractions (relative standard deviations, below
5.3%, <i>n</i> = 6). The proposed method was applied to
analyze PAHs in real river water samples
