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In order for extraction and analysis of volatile and semi-volatile chemicals from sample matrix, simple gas flow headspace-liquid phase microextraction (GF-HS-LPME) method was developed. Based on the original HS-LPME technique, gas flow procedure was added to increase enrichment factor. The GF-HS-LPME parameters such as gas flow rate, heating and cooling temperature, extraction time and position of solvent microdrops etc were optimized. In comparison to steam distillation, the new method is simpler in sample preparation, requires less sample mass, and produces better repeatability (RSD < 20%) and shortens extraction time. This method provides also high stability for water, oxygen and thermally unstable chemicals. It is important to note that this new method was able to detect three hydrolysis compounds such as triphenyl Phosphoric ester, (2-isopropyl)phenyl diphenyl phosphoric ester and tri(2-isopropylphenyl) phosphoric ester from Wild Millet whereas the steam distillation method was not able to detect those compounds. Under the optimized conditions, detection limit (S/N) was 0.020~200 ng for PAHs which was 10 times higher than those in original HS-LPME. Therefore, it is concluded that the GF-HS-LPME is a simpler, faster and more economical method than the conventional steam distillation technique for intact determination of volatile and semi -volatile chemicals from environmental samples. |
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Keywords:Essential oil;Volatile and semi-volatile chemicals;GC-MS;Plant |
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