Effect of water volume on SPME

The effect of water volume on SPME efficiency was evaluated using three different volumes 2, 4, and 8 mL, while the concentration of analytes remained flie same. As shown in Table 2, the peak area ratio (the peak area of analyte divided by the peak area of the internal standard) increased about 10 times when the volume was increased from 2 to 4 mL. However, when water volume further increased from 4 to 8 mL, only slight enhancement of peak area ratios was found. Since the volume of water extracts after flie hot water extraction of rosemary was 5 mL, the 4 mL of water voliune was chosen in this work. 

Table 2. Effect of Water Volume on SPME Efficiency...

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