Direct Thermal Extraction Analysis of Solid and Liquid Samples using the GERSTEL MPS Robotic Sampler, Thermal Desorption Unit (TDU 2) and Cooled Inlet System (CIS)


App Note 205/2019

Direct thermal extraction (DTE) is a thermal desorption technique in which a small amount of sample, typically 10-50 mg, is placed in an empty fritted thermal desorption tube or into a small vial (μ-vial) within an empty thermal desorption tube. The sample is then heated in a thermal desorption unit under a flow of inert gas, in order to release volatile and semi-volatile compounds. The analytes are trapped and finally determined by GC/MS. DTE requires little sample preparation and can be used for trace analysis of volatile and semivolatile organic compounds in solid or liquid samples. Exhaustive extraction conditions can be developed for an analyte by optimizing temperature, flow rate and extraction time. Calibration and quantification can be performed by externally spiking standards onto Tenax-TA® filled sorbent tubes. This study describes the use of the GERSTEL MPS with CIS, and TDU for the analysis of volatile and semivolatile compounds in solid and liquid samples.