tailieunhanh - Introduction to Modern Liquid Chromatography, Third Edition part 56

Introduction to Modern Liquid Chromatography, Third Edition part 56. High-performance liquid chromatography (HPLC) is today the leading technique for chemical analysis and related applications, with an ability to separate, analyze, and/or purify virtually any sample. Snyder and Kirkland's Introduction to Modern Liquid Chromatography has long represented the premier reference to HPLC. This Third Edition, with John Dolan as added coauthor, addresses important improvements in columns and equipment, as well as major advances in our understanding of HPLC separation, our ability to solve problems that were troublesome in the past, and the application of HPLC for new kinds of samples. . | 506 QUALITATIVE AND QUANTITATIVE ANALYSIS Figure Common integration errors a Improper peak-start assignment by the presence of a negative peak prior to analyte peak. Arrow shows move to a new peak-start point for proper integration dashed line b Improper integration of overlapping peaks perpendicular drop tangent skim dashed line gives proper integration c Improper location of peak-end point. Arrow shows move to a new peak-end for proper integration dashed line . different systems . Rather than tryingto find thcpcak-ciidpoiiit using the normal processes theintegrscorwillnow autornatifiant iissigiiictothtfooocUtinis pornt for all clironiato arne iitagoodpractioc tovitiioUy cxomiiioevcry clrcomctogram to confirm that ihe integrat-gn hcorraet acd tomake oeacttaryahJ clttmenlti0il hoot. Some users feel that it is cheating to adjust baselines after the initial integration is done but lhecimplefaccis thetadaiesyctern cannel poopar yintegaatealtpcsks all the anysochmanucl br-eline ehengar must bocarrsrO rci consistency andwithascreference tsaOetired answer. AaCiiion Sugg. ions The e e Oicgrrioie t mje a . ticn e . .c- hes cmbme t a well-inraanirtti irt romarggrpabiThrsi ngaee nt Oucs o- systems is very sophtsticated and ts destgned to properly tdenttfy peaks adjust basehnes determme bunching rates and so forth. When starting a new method it usually is most efficient to run several representative samples and allow the integrator to assign the initial sootiago. Ofisr oharesolts havcbeen rev wr i thie gor-etsigntd petrinae can be adjusted re ooreeiO foe ecnsittent erroos todsdcsemareonn ofevo perhc by a perpaoaicntardropco a firsi lel bte Integrator operate intia ueoad way ernldic n make omy necresary chcngeo io sertingsat needed. To hoOp jrroteao desa ineegrito cha pharmoceoticalinguslsyhat o tar eO regulations called thearoatromccignatmeseulet ond icrecicyltobrdlrirCrtiei ohn 21 CFR Preet It a iOnereoniramrnt uCsOc .