2007-2. How Little Can I See?

With trace analysis, a lower limit of detection is always welcomed. LCGC 25(2) 142-152 (2007) John W. Dolan Errata: There is an error in equation 1 of this month’s column. See LCGC 26(5) (2008) for complete explanation. In the November installment of “LC Troubleshooting” [LCGC 24(11) 1184-1190 (2006)], the y […]

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2006-12. Method Reproducibility — A Case Study

Excess variability is not acceptable in a pharmaceutical method. LCGC 24(12) 1274-1278 (2006) Nastaran Sigari and John W. Dolan Erratum: Note that equation 5 for USP tailing factor is not correct. It should read: TF = w(total)/2*w(front).

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2002-9. Performance Qualification of LC Systems

Chromatographers can use a simple set of tests to check system performance. LCGC 20(9) 842-848 (2002) Gerald Hall and John W. Dolan Note that there are several errors in this document. The y-axis scale on Figure 1 should be microvolts, not millivolts. The calculations for Figure 1 are OK, but […]

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