1. The homogeneity testing of EtG in hair reference materials: A high-throughput procedure using GC–NCI–MS 
Bettina Mönch, Roland Becker, Christian Jung, Irene Nehls 
Forensic Science International 
Volume 226, Issue 1, Pages (March 2013)
DOI: /j.forsciint
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2. Fig. 1
Optimization of time and temperature of the derivatization reaction of EtG with PFPA.
Forensic Science International  , DOI: ( /j.forsciint )
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3. Fig. 2
Gas chromatograms of materials 1 and 2 after extraction and derivatization with PFPA. SIM mode, mass traces m/z 496 (EtG derivative) and m/z 501 (EtG-d5 derivative).
Forensic Science International  , DOI: ( /j.forsciint )
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4. Fig. 3
Recovery of EtG from aqueous hair extracts after prolonged storage at −26°C (p=3 injections).
Forensic Science International  , DOI: ( /j.forsciint )
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5. Fig. 4
Stability of the EtG derivative stored at 9°C for different times. On each day four separate derivatizations of a pooled extract were analyzed (p=3 injections).
Forensic Science International  , DOI: ( /j.forsciint )
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6. Fig. 5
Result of the homogeneity study using the validated method on hair reference material 2. Bottle means and standard deviations (p=2 subsamples analyzed, each derivatized extract injected n=3 times).
Forensic Science International  , DOI: ( /j.forsciint )
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