Another USP Chapter <621> update?
Starting with the obvious – the USP <621> chapter on system suitability calculations has (once again!) been updated.
I know we were all prepared for the switch to harmonize the calculations for Resolution, Plate count, and signal-to-noise from the USP to match the EP and JP, but on Aug. 25, 2023, the USP announced there would be a return to the prior calculation for USP signal-to-noise with an official, revised, version of <621>1 being posted on Oct. 1. The rest of the harmonized calculations have not been impacted and the implementation date for methods is set for May 1, 2025.

For those wishing to report the harmonized Plate count and Resolution calculation in Chromeleon chromatography data system (CDS), configure your Plates and Resolution columns to report the “EP Formula” instead of the “USP Formula” as outlined by our v.2.0 support article USP 621 Harmonization – Chromeleon Guidance2 and demonstrated in the video below.
Video: Calculation options featuring USP <621> calculations

Chromeleon CDS was engineered to give flexible options and the preceding video goes through some of the ways to calculate updated values without having to upgrade or change anything. All of these skills can be applied to reports, too.
Resources
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