C30 17Alpha-Hopane
Definition
The C30 pentacyclic triterpane used as the primary internal normalisation standard in petroleum biomarker fingerprinting. It is resistant to evaporation, biodegradation, and photooxidation, making it the preferred reference compound for correcting weathering-induced changes in other biomarker concentrations.
- Type
- C30 pentacyclic triterpane biomarker
- Use
- Internal normalisation standard in petroleum fingerprinting
- Key property
- Resistant to evaporation, biodegradation, photooxidation
- Detected by
- GC-MS in selected ion monitoring mode
Common questions
Why is resistance to weathering important for a normalisation standard?+
Petroleum spilled or spread at a scene loses volatile components to evaporation and can be partly biodegraded before sampling. Normalising other biomarker peaks against a compound that barely changes under these processes lets examiners compare weathered and fresh samples on a consistent basis.
How is C30 17alpha-hopane actually used in a comparison between a suspect source and a spill sample?+
Examiners ratio target biomarker and diagnostic compound peaks against the hopane peak in both the questioned sample and reference source, producing weathering-corrected ratios that can be compared directly to assess whether the two petroleum products share a common origin.
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