Development of a Method Based on the Needle-trap Microextraction Filled with Hydroxyapatite and Polyaniline Nanocomposite for Determination of Volatile Organic Compounds in the Air

In this study, the efficiency of packed needle trap with hydroxyapatite/polyaniline (NTD-HAP/PA) nanocomposite was assessed in air sampling and analysis of a hazardous group of VOCs such as benzene, toluene, ethylbenzene and xylenes. The effects of main parameters, including desorption temperature and time, were evaluated on the performance and carryover of prepared NTDs. Moreover, the repeatability, reproducibility and stability of the developed sampler were investigated for the sampling and determination of the interest analytes. The results of experiments indicated that the highest peak area was obtained at desorption temperature and time of 250˚C and 3 min, respectively. The reproducibility of the proposed method was investigated with three distinct NTDs with similar structure. The weight of the adsorbent also was obtained results showed that the relative standard deviation (RSD) of experiments was in the range of 0.2-9.7%. The RSD of repeatability was obtained at four different concentrations, with three times replications less than 15%. The Limit of Detection and Quantitation (LOD and LOQ) for the studied VOCs ranged from 0.01 to 0.14 ng/mL and 0.04 to 0.48 ng / mL, respectively. Also, the storage stability of the analytes of interest in the NTD-HAP/PA after 3 and 7 days at 4 °C was above 95 and 93%, respectively. It can be concluded that the proposed method could be applied as a desirable and powerful tool for air sampling and microextraction of volatile organic compounds