TY - JOUR
T1 - Identification of alkylpyrazines by gas chromatography mass spectrometry (GC-MS)
AU - Xu, Sihang
AU - Errabelli, Ramu
AU - Feener, Donald H.
AU - Noble, Katherine
AU - Attygalle, Athula B.
N1 - Publisher Copyright:
© 2019 Elsevier B.V.
PY - 2019/3/29
Y1 - 2019/3/29
N2 - Pyrazines are an important group of natural products widely used as food additives and fragrants. Gas chromatography-mass spectrometry (GC–MS) is the most widely applied analytical technique for characterization of alkylpyrazines. However, mass spectra of many positional isomers of alkylpyrazines are very similar. Consequently, an unambiguous identification of each positional isomer by spectral interpretation or database search protocols is practically unfeasible. In fact, there are many misidentifications in literature. To identify alkylpyrazines, chemists often resort to gas chromatographic retention indices (RIs). Although there are many compilations of retention indices of alkylpyrazines, these databases are often incomplete and the values reported are sometimes inconsistent. Herein, we present retention indices of fifty-six alkylpyrazines recorded on DB-1, ZB-5MS, DB-624, and ZB-WAXplus stationary phases, and compare them with those available in the NIST-2017 MS-RI database. Furthermore, we demonstrate how RI values can be used, together with mass spectral interpretations, to identify certain alkylpyrazines unambiguously.
AB - Pyrazines are an important group of natural products widely used as food additives and fragrants. Gas chromatography-mass spectrometry (GC–MS) is the most widely applied analytical technique for characterization of alkylpyrazines. However, mass spectra of many positional isomers of alkylpyrazines are very similar. Consequently, an unambiguous identification of each positional isomer by spectral interpretation or database search protocols is practically unfeasible. In fact, there are many misidentifications in literature. To identify alkylpyrazines, chemists often resort to gas chromatographic retention indices (RIs). Although there are many compilations of retention indices of alkylpyrazines, these databases are often incomplete and the values reported are sometimes inconsistent. Herein, we present retention indices of fifty-six alkylpyrazines recorded on DB-1, ZB-5MS, DB-624, and ZB-WAXplus stationary phases, and compare them with those available in the NIST-2017 MS-RI database. Furthermore, we demonstrate how RI values can be used, together with mass spectral interpretations, to identify certain alkylpyrazines unambiguously.
KW - Gas chromatography
KW - Mass spectrometry
KW - Pyrazines
KW - Retention indices
KW - Stationary phases
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U2 - 10.1016/j.chroma.2019.01.011
DO - 10.1016/j.chroma.2019.01.011
M3 - Article
C2 - 30655029
AN - SCOPUS:85059841337
SN - 0021-9673
VL - 1589
SP - 149
EP - 161
JO - Journal of Chromatography A
JF - Journal of Chromatography A
ER -