4.2.2. Peak identification
Peaks from the chromatogram were identified based on their
mass spectra and linear retention index values. Mass spectra for
unknowns were compared with standards from NIST 2005
(National Institute of Standards and Technology, Gaithersburg,
MD) mass spectra database. Only spectral match values of >900
with an LRI value with 1% of standards were considered for identification.
Linear retention index, LRI, values (formerly, Kovat’s index
values) of chromatographic peaks on Stabilwax column were
determined using a series of alkanes (C5–C25) run under identical
conditions for GC–MS.