The US Pharmacopoeia, Chapter 621 Chromatography, has been updated. Effective December 2022, the USP changed the formulas for Resolution and Plate Count. What is Waters doing in Empower? - WKB231916

ENVIRONMENT

• Empower 2
• Empower 3

ANSWER

Waters is aware of these changes which use the width at 50% height approach (rather than the width at tangent approach) for the determination of Resolution (R) and Plate Count (N or Plate Number).  The future definition of Signal-to-noise ratio continues to define the range of the noise to be observed over a distance equal to or greater than 5 times the width at 50% height of the peak. Noise should be determined using a blank injection. 

Empower does determine these calculations appropriately in current versions of Empower and has made changes in Empower 3.8.0 to further comply with the changes in this USP chapter. Please reference the document CRI-4304 Redefined USP Calculations June 2023.pdf for further information.

This request is documented as CRI-4304.

ADDITIONAL INFORMATION