Page 177 - Basic Gas Chromatography
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163                             (SIM).   compares   its   in   latest   acquisition   is   (typi-   rate   is   data   qualitative   trace   way   a   to  exposed   the   obtained   and   selected   trap   synthesis,   pesticides,   of  chiral-   compounds   resolution   provides
                                   monitoring   rapidly   spectra   the   with   data   sensitivity   points).   data   ions   of   acquisition   quantitative   for   for   mode   level.   such   in   again   from   that   to   MS/MS),   as   called   ion  newer   the   in   (drugs,   significance   chiral   high   GC




                       Dioxide   Phenol   A   ion  selected   base   reference   seconds   The   slow;   is   few   (too   number   data   so   used   be   best   the   ppb   operated   are   fragmentation   similar   to   is  operation   some   step   compounds   of  the   regulating   for   need   capillary   by


                       Caton       ——~   and   (TIC)   data   150,000   few   a   only   analysis.   range  selected   optimal   small   a   only   faster   a   is   second),   cannot   SIM   is   it   but   the   to   down   be   to   it   process   secondary   is   result   referred   of   in  available   essential   an   the   and   separation



           gv?"          Water   Time   chromatogram   computer   The   over   with   requires   qualitative   the   not   is   however,   There   1   (~   peak   improved.   scanned),   often   allows   [7]   ionization   the   a   The  (CID).   (usually   mode   This   is   is  HPLC   chiral   of   understanding   legislation   stringent,   Chiral


                       AMU   fj                   desired   in   monitored.   trap   causing   spectrometer   and   GC   or   utilization   an   increases,   and
           18                       ion    peak.   spectra   ions   GC   are   ion   from   selectivity.   GC   As   increases.
           =              |                  spectrum   of   the   all   quantitation   monitoring,   the   greatly   compounds,   the   dissociation   (SRM)   BY   either   the   etc.).
   GC      m/z         10-200       of  total   each   scan   are   of   is   masses   of   fragments   molecules   mass   by   and   activity   widespread
   by      SIM:        TIC:         Comparison   identify   mass   Matching   achieving   to   usually   ion   6)   as   lifetime   sensitivity   all   targeted   version   stage   higher   monitoring   instruments.   ANALYSIS   pheremones,   techniques
    Analysis                               to   unknown   files.   systems,   necessary   and   selected   many   the   and   (not   of   newer   original   gas   collision-induced   dual   even   separation   characterization   biological   more



    Chiral                          10.12.   Fig.   used   be   each   library   data   rate   limited,   In   as   cally   during   better   analyses   analysis   A   the   that   energetic   a   by   provides   reaction   GC-MS   CHIRAL   Chiral   flavors,   on   ity   becomes   separation









    Topics                                       spectrum   is   result   Ion   10.12).   A   peaks   and   i   140

    Special                     CH,CH,t   29   40   (EI).   the   of   the   and   (TIC—Total   (SIM—Selected   Fig.   (see   compounds.   Daltons.   All   computer   ]   I   120
                          a.    CHsCH2CH;t   43   75   mass  spectrometer   100%   as   it  plots   peak,   base   10.11).   scan   total   a   ions  individual   compound   unknown   400   to   40   the   from  retrieved   I   ]      100   (EI).  hexane




          CHsCH2CH2CHsCHeCHs   Hexane   ke   [CHsCH2CH2CH2CH2CHs]   ion,  Molecular   = 86)   me   CHsCH2CH,CH,*   57   peak)  (base   100   a   in  hexane   of   system   data   the   relative   the   to   Fig.   (see  n-hexane   either  ways;   as   of  number   particular   a   of   identify   to   used   is   example  scanned—for   can  spectra   be   CgHy4;   86   =   WT.  MOL.   57   Livi       80   60   FI   of  spectrum   Mass
                   +e
                        M+®







                          Z
                               CHgCH2CH,CH,CH;*   ‘71   Relative   10   (%):   Fragmentation   10.10.   Fig.   and   peak,   base   the   plotted   are   peaks   mass   of  spectrum   two   in  plotted   be   as   or   small   a   characteristic  Monitoring)   chromatogram   ion   is   range   mass   mass   the   so   f-   100   43   F   60   99   40F   20   I   0     ]       20   40   10.11.   Fig.











   162                            m2.:   abundance   called   is   Other   scale.   typical   a   can   Data   Chromatogram)   Ion   total   A   specified   reported   are   REL.   ABUND.   *
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