| gas chromatography |
[ Advanced Quantitative Test for DDT Detection ]
DDT and its derivatives, DDE and DDD, can measured in biological samples primarily by gas chromatographic assays. Gas chromatography provides high resolution and retention time, which is ideal for distinguishing between the different isomers of DDT.
» Gas chromatography has been historically coupled with electron capture detection and mass spectrometry quantitative techniques. With the availability of gas chromatography-mass spectrometry instrumentation in analytical laboratories, it is now possible to quantify DDT and its metabolites. Both the GC/ECD and GC/MS analytical methods are suitable for the analysis of DDT, DDE, and DDD. However, the GC/ECD method typically provides greater detection sensitivity, whereas the GC/MS method has the advantage of providing qualitative information to determine the specificity of the analysis.
Serum is extracted with hexane. The extraction is conducted for 2 hours on a slow speed rotating mixer. If emulsion forms, centrifugation may be used to effect separation. An aliquot of the hexane layer is quantitatively transferred to an evaporative concentrator tube to which a micro-snider column is affixed. The extract is concentrated in a water bath, and the final volume is adjusted to correspond to the expected concentration of the pesticide residue. A suitable aliquot is analysed by electron capture gas chromatography.
This test is the most recommended quantitative test for biological samples, especially blood.
Isomer Detected with its Limit:
*For the reference of the test (CLICK HERE).
**For more information about analytical methods for DDT testing, refer to document attached below. (Source)