Dynamic headspace vacuum transfer "in trap" extraction method and apparatus

A headspace extraction and analysis method for volatile compounds, wherein a continuous flow of volatile compounds is forced by applying reduced pressure conditions, comprising

• (i) inserting a needle of a sampling means via a septum into a headspace above a solid or liquid sample contained in a container closed by said septum, wherein said sampling means has a trap filled with at least one sorbent, said trap has a first end and a second end, at the first end the trap is connected to the needle, and at the second end the trap is connected with at least one flow channel configured to connect the trap to a vacuum source and an inert gas source,
• (ii) applying a vacuum to the sampling means on the side of the second end of the trap, so that volatile compounds in the headspace are sucked out from the container into the trap,
• (iii) removing the sampling means from the container,
• (iv) drying the sampling means by flowing a dry inert gas through the sampling means from the second side,
• (v) inserting the needle into an injector of a gas chromatography apparatus,
• (vi) desorbing the volatile compounds from the trap by flowing inert gas through the at least one sorbent from the second side,
• (vii) analyzing the volatile compounds and
• (viii) cleaning the trap and needle by flushing with inert gas.