LAUSR

A new simple, low-cost, reliable vacuum-assisted headspace solid-phase microextraction (VA-HS-SPME) device was fabricated and evaluated considering the strengths and weaknesses of previously reported systems. The device can be applied for analysis of solid and liquid samples without sample loss or vacuum loss during the evacuation process, in contrast to similar setups. Additionally, it is simpler, lower cost, and more operator friendly for direct extraction of volatiles and semivolatiles from complicated solid matrices. It was coupled with gas chromatography-flame ionization detection (GC-FID) and applied for direct extraction and determination of polycyclic aromatic hydrocarbons (PAHs) in polluted soil samples, without any sample preparation steps. Parameters affecting the performance of the developed method, such as extraction temperature and time, vacuum level, volumes of vacuum chamber and sample vial, and desorption condition, were investigated and optimized. Under the optimal conditions, calibration curves were linear over the range of 0.01–2 μg g−1 (R2 > 0.996). The limits of detection (LODs) were found to lie in the range of 0.3–0.8 ng g−1, while the relative standard deviations (RSDs) for six replicate analyses were 5.3–7.1%. The developed VA-HS-SPME/GC-FID procedure was used for ultrasensitive determination of PAHs in contaminated soil samples; the results were statistically in agreement with those obtained using a validated ultrasonic solvent extraction (USE) method.Graphical Abstract