Mrs/Miss Ostadgholami,

There is not needed preliminary exctraction of the analyte.

You can carry out direct analysis and quantification according to our more recently developed quantitative mass spectrometric concept and model equations (Consider the references [2,3] to my answer to discussion [A].)

The quantification can be carried out using the very characteristic Cl-isotope shape of 3-chlor-1,2-propandiol and its few fragment products.

[A] [https://www.researchgate.net/post/How_can_we_detect_VOCs_in_exhaled_breath_sample_using_ISQ_7000_single_quadrupole_GC-MS_system]

Have a look at GERSTEL's MCPD solution. It automates ISO18363-1 (and equivalent methods). GERSTEL have fully automated the analysis (overview of protocol: www.gerstel.com/en/3-mcpd-sampleprepsolution.htm).