Skip to main content

A Detailed Mechanistic Fragmentation Analysis of Methamphetamine and Select Regioisomers by GC/MS

Buy Article:

$51.00 plus tax (Refund Policy)



A novel ring-substituted methamphetamine regioisomer, N,α,4-trimethyl phenmethylamine, was synthesized in order to study the validity of proposed structures for various mass spectrometry (MS)-derived peaks in a methamphetamine fragmentation pattern. While other research efforts have studied aspects of methamphetamine in detail, a full fragmentation study has not been reported previously. In addition to showing molecular structures represented by fragment peaks, mechanisms for selected processes are detailed. An empirically derived procedure to easily determine by simple spectral peak pattern recognition the geometry of dimethyl- or ethyl-substituted immonium ions (RRC=N+RR) where m/z=58 is outlined. These results are platform independent for electron ionization (EI) instruments, but have also proven to be helpful in explaining spectral peaks observed in spectra from ion trap systems. The spectrum for the synthesized methamphetamine regioisomer was accurately predicted using this methodology. While this approach is useful in some casework, the converse may be more useful: when an unexpected or unusual peak pattern arises in a spectrum, being able to analyze it to determine the structure of the molecule. This paper gives an analyst the means to begin such retro-synthetic analyses.

Keywords: forensic science; fragmentation; gas chromatography/mass spectrometry (GC/MS); mechanism; methamphetamine isomers; narcotics analysis; spectra interpretation

Document Type: Research Article


Affiliations: San Francisco Police Department Crime Laboratory, 850 Bryant St., San Francisco, CA 94103.

Publication date: March 1, 2007


Access Key

Free Content
Free content
New Content
New content
Open Access Content
Open access content
Subscribed Content
Subscribed content
Free Trial Content
Free trial content
Cookie Policy
Cookie Policy
Ingenta Connect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more