2017-6. Method Adjustment the USP Way

When you want to adjust a United States Pharmacopoeia (USP) method for a different size column or to meet system-suitability criteria that fail, how much of a change can you make without revalidating the method? LCGC 35(6) 368-373 (2017) John W. Dolan  

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2012-11. Evaluation of an LC Method

How can we tell if a liquid chromatography method is working properly? How can a compendial method be adjusted to speed up the run time? LCGC 30(11) 972-977 (2012) Fatos Osmani and John W. Dolan

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2009-8. Too Many Changes

Remember the Rule of One — change just one thing at a time LCGC 27(8) 606-610 (2009) John W. Dolan Erratum: LCGC 27(6), p 478. Table 1, in the third column, the next to last line should read 403913, not 36827, and the 36827 should shift down one row.

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2007-1. Questions From India

Chromatographers worldwide suffer from the same problems. LCGC 25(01) 34-38 (2007) 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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