LCGC The Peak - July 2008 - (Page 14) 14 THE PEAK JULY 2008 Table I: Compounds used in study Compound Designation A B C D E F G H I Common Name 4-ethoxyacetanilide sulfamethoxazole benzocaine m-cresol acetophenone m-nitroaniline caffeine acetaminophen TSO (trans-stillbene oxide) Molecular Weight 179.22 253.30 165.5 118.95 120.15 138.13 194.19 151.17 196.25 Figure 4: Gradient reversed-phase HPLC separation of compounds G and H using a C18 column. 5–95% linear gradient (water–acetonitrile with 0.1% formic acid [v/v] in each) over 9 min through a 150 mm 4.6 mm Waters Symmetry Shield C18 column at 1.5 mL/min. all three columns, resolution again increased as a function of decreasing methanol concentration. In agreement with other studies (14), while resolution is greatest at 3% methanol for all columns in the previously shown experiments, the peak shapes broadened when less co-solvent was used (data not shown). Most intriguingly, all three columns readily gave baseline resolutions of G and H, in contrast to the near co-elution observed with a typical C18 reversed-phase HPLC gradient. Encouraged by these findings, a six-component mixture (compounds A–F) was examined. Under typical C18 reversed- Table II: Retention order by SFC and isocratic RP-HPLC Compound Designation E D C A F B Common Name acetophenone m-cresol benzocaine 4-ethoxyacetanilide m-nitroaniline sulfamethoxazole Molecular Weight 120.15 118.95 165.50 179.22 138.13 253.30 Rt order SFC 1 2 3 4 5 6 Rt order LC(MeOH) 3 5 6 4 2 1 Rt order LC(ACN) 4 5 6 2 3 1
Table of Contents Feed for the Digital Edition of LCGC The Peak - July 2008 LCGC The Peak - July 2008 Contents From the Editor Evaluation of Nonpolar Reversed-Phase Columns Under Supercritical Conditions Enhancing GC–MS Analysis of Trace Compounds Using a New Dynamic Approach to Reducing Background Interference Industry News Events Education LCGC The Peak - July 2008 LCGC The Peak - July 2008 - LCGC The Peak - July 2008 (Page Cover1) LCGC The Peak - July 2008 - LCGC The Peak - July 2008 (Page Cover2) LCGC The Peak - July 2008 - LCGC The Peak - July 2008 (Page 3) LCGC The Peak - July 2008 - Contents (Page 4) LCGC The Peak - July 2008 - Contents (Page 5) LCGC The Peak - July 2008 - Contents (Page 6) LCGC The Peak - July 2008 - From the Editor (Page 7) LCGC The Peak - July 2008 - Evaluation of Nonpolar Reversed-Phase Columns Under Supercritical Conditions (Page 8) LCGC The Peak - July 2008 - Evaluation of Nonpolar Reversed-Phase Columns Under Supercritical Conditions (Page 9) LCGC The Peak - July 2008 - Evaluation of Nonpolar Reversed-Phase Columns Under Supercritical Conditions (Page 10) LCGC The Peak - July 2008 - Evaluation of Nonpolar Reversed-Phase Columns Under Supercritical Conditions (Page 11) LCGC The Peak - July 2008 - Evaluation of Nonpolar Reversed-Phase Columns Under Supercritical Conditions (Page 12) LCGC The Peak - July 2008 - Evaluation of Nonpolar Reversed-Phase Columns Under Supercritical Conditions (Page 13) LCGC The Peak - July 2008 - Evaluation of Nonpolar Reversed-Phase Columns Under Supercritical Conditions (Page 14) LCGC The Peak - July 2008 - Evaluation of Nonpolar Reversed-Phase Columns Under Supercritical Conditions (Page 15) LCGC The Peak - July 2008 - Evaluation of Nonpolar Reversed-Phase Columns Under Supercritical Conditions (Page 16) LCGC The Peak - July 2008 - Evaluation of Nonpolar Reversed-Phase Columns Under Supercritical Conditions (Page 17) LCGC The Peak - July 2008 - Enhancing GC–MS Analysis of Trace Compounds Using a New Dynamic Approach to Reducing Background Interference (Page 18) LCGC The Peak - July 2008 - Enhancing GC–MS Analysis of Trace Compounds Using a New Dynamic Approach to Reducing Background Interference (Page 19) LCGC The Peak - July 2008 - Enhancing GC–MS Analysis of Trace Compounds Using a New Dynamic Approach to Reducing Background Interference (Page 20) LCGC The Peak - July 2008 - Enhancing GC–MS Analysis of Trace Compounds Using a New Dynamic Approach to Reducing Background Interference (Page 21) LCGC The Peak - July 2008 - Enhancing GC–MS Analysis of Trace Compounds Using a New Dynamic Approach to Reducing Background Interference (Page 22) LCGC The Peak - July 2008 - Enhancing GC–MS Analysis of Trace Compounds Using a New Dynamic Approach to Reducing Background Interference (Page 23) LCGC The Peak - July 2008 - Enhancing GC–MS Analysis of Trace Compounds Using a New Dynamic Approach to Reducing Background Interference (Page 24) LCGC The Peak - July 2008 - Enhancing GC–MS Analysis of Trace Compounds Using a New Dynamic Approach to Reducing Background Interference (Page 25) LCGC The Peak - July 2008 - Industry News (Page 26) LCGC The Peak - July 2008 - Events (Page 27) LCGC The Peak - July 2008 - Events (Page 28) LCGC The Peak - July 2008 - Events (Page 29) LCGC The Peak - July 2008 - Education (Page 30) LCGC The Peak - July 2008 - Education (Page 31) LCGC The Peak - July 2008 - Education (Page 32) LCGC The Peak - July 2008 - Education (Page Cover4)
For optimal viewing of this digital publication, please enable JavaScript and then refresh the page. If you would like to try to load the digital publication without using Flash Player detection, please click here.