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111   of   above   [9]   times   LOQ   have   detec-   are   high   on   curve   can   of   is   the   New

           detectors   be  should   analysis   LOQ   ten   the   that   may  agencies   specify   to   They   them.   at  nonlinear   limit  of  linearity   plotted   often   the   and   of  sensitivity   one   concentration   (sensitivity)   linearity   of   limit   equal   95%   to   figure   the   in   and  sensitivity,       permission.   with   Inc.,   Sons,   &




           between  limits   which  (LOQ)   environmental   the   and   S/N   and   state   also   Other   need  same   between   became   upper   the   Figure   is   7.6   minimized   are   is   plot  better   analyte   the   y-axis   the   upper   the   a sensitivity   dashed   line   maximum   limit   r  Upper   f   linearity   of   N   107!   10-2   carrier  gas   Reprinted  ASTM.   Wiley   John   Inc.  Sons,




           detection   on  guidelines   the   times   similar   [10].   LOD   the   with   relationship   and   off   establish   to   Since   linearity   A   Here   7.7.   while  range   specification,   to   upper   The   the       range     1   1073   the   in  detector  (mg/mL)   Copyright   Contrasts,   and   &   Wiley



           compare   quantitation   of   ACS   three   be   are   USP   the  times   concerned   the   and   curved   necessary   range.   from   deviations.   Figure   in   large   ASTM   corresponding   sensitivity.   representing   that   value.   Linear   10-4   n-butane   of   the   TCD.   a   Concepts   John   of


           to   limit   the   should   the   of   two   all   are   limits,   7.6  Figure   becomes   linear   the   deviations   show   to   shown   a   get   to   the   point   of   0.95   10-5   Concentration   at   of   plot   Chromatography:   courtesy

     Characteristics   convenient  measure   types.   the   is   term   example,   For   LOD   the   The  definitions   than   less   no   but  guidelines,   quantitation   same.   in   line   It   measure   the   scale,   use   to   one   concentration   as   scale   log   a   to  According   concentration   measured   the  through   is   line   fog   Minimum   ini   detectability   Yo       10-6   linear   of  a  Example   M.,   J.   Reproduced





    Detector   a   is   it   different   related   A   LOD.   the   that  specify   S/N.   the   be  should   other   and   tion   the   not   Linear  Range   The  straight   concentrations.   to  order   in   a  log-log   good   a   not   is   versus   on   be   can   linear.   be   analyte   the   is   maximum   the   drawn   dashed   lower   (Buu/qwW  ‘Aud)  AyAnisuas,   7.7.   Fig.   Miller,  From   p.   1987,   York,











    Detectors                                  Re-  ASTM.   John  Contrasts,   Inc.   Sons,   eventually   phenomena   be   can   detectable   IUPAC   3)   that  Note   discussed   units   The   mg/sec   the   of   the   used,   mass   the   of   such,   As




               |   |   |   !   |   |   |   !   of   range   Copyright   and   &   Wiley   John   and   lost   These   that   limit   minimum   The   defined.   definition   level.   and  detector   width   peak   are   units   minimum   the   dilution   the   MDQ.   the
                               —-——_—-_»]   Upper   limit   dynamic   carrier  gas   TCD.   a   for   Concepts   of  courtesy   is  linearity   concentration.   lower   the   as   such   detectivity.   and   as,   just   as   the   with   noise   the   type   the   by   appropriate   represents   for  allowing   this  value






                     mg/mL     range        the   in  n-butane   (mg/mL)   range   Chromatography:   Reproduced   graph,   linearity.   on   representing   names   of   (LOD),   D,   sensitivity   accordance   twice   be   concentration   multiplied   the   and   call  Some

                     10-6      Dynamic      detector   dynamic   M.,   the   increased   detectability,   p=   the   is   should   is   if   mg   of
                     x                    of   the   of   J.   96.   of   section   variety   detection   S   in   a   and   chromatographically,   process.
                     1                             p.                  7.6,                 2
                     =                    Concentration   at   definition   Miller,   1987,   end   with   the   a   by   and   by   signal   for   detectability   units
                     detectability             the   From   York,   upper   increase   in   later   Figure   called   of   limit   minimum   level   multiplied   mg/mL   type.   measured,   the   has   the   from


                     Minimum                   of  Illustration   permission.   New   Inc.,   the   at   to   fails   discussed   Detectability   on   point   been   (MDQ),   the   noise   the   is   detectable   a   are   rate   flow   minimum   being   results   detected   results



                                                   Sons,   shown         has   defined    is   numerator   that   detectability   peak   be   that
                   (Aud)  JeUBIS  10}93}38q      with        signal    lowest                      mass   the   that   can
                                               7.6.   &    As   be   Minimum   detected,   quantity   has   where N   a   If   analyte   sample
     110                                       Fig.   printed   Wiley   the   will   The   [8]   the   earlier   of   for   value   that
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