Factorial Design Optimization of Solid-Phase Microextraction for High-Performance Liquid Chromatography−Ultraviolet Spectrometry Analysis of Polycyclic Aromatic Hydrocarbons in Cigarette Filter Tar

A simple and rapid procedure for the determination of polycyclic aromatic hydrocarbons (PAHs) in cigarette filter tar using solid-phase microextraction (SPME) was developed. The analysis was carried out using high-performance liquid chromatography equipped with an ultraviolet detector. The effects of the SPME experimental parameters on the extraction recovery were studied simultaneously using a central composite design (CCD) after a 26−2 fractional factorial experimental design. The SPME variables of interest were the extraction temperature, the extraction time, and the stirring speed, as well as the pH and the concentrations of NaCl (%, w/v) and acetonitrile (ACN). The optimal SPME conditions were as follows: an extraction temperature of 65°C, an extraction time of 50 min, a stirring speed of 800 rpm, 0% NaCl (w/v), 10% ACN in the sample, and a source pH of 8.0. The extraction calibration plots were linear over the range of 0.25−20 ng mL−1 (r2 > 0.9912) and the limits of detection (LODs) for the 6 PAHs studied were from 0.17–5.02 ng cigarette−1. The relative standard deviation (RSD) ranged from 7.1–13.5% for intra-day variation and from 8.5–18.4% for inter-day variation. The performance of the proposed method was evaluated for extraction and determination PAHs in real samples (various brands of cigarettes). The total amounts of all of the studied PAHs found in the filter tar of the three brands of cigarettes were 320.2, 17.9, and 66.7 ng cigarette−1, respectively.