The Chinese Pharmacopoeia 2025 Edition*, Part IV, the assay for “Citrate Ion” by high‑performance liquid chromatography specifies the use of a column packed with styrene–divinylbenzene copolymer–based cation‑exchange resin (hydrogen form) with dimensions of 7.8 mm (I.D.) x 300 mm (L) and a particle size of 9 or 8 µm**. SUGAR SH1011 column confirmed the requirement was met. For this analysis, use of a guard column is recommended.

System suitability requirementCorrelation coefficient of linear regression (R²): ≥ 0.999

*The version at the time of the application acquisition.
**Chinese Pharmacopoeia 2025 edition allows changes in column dimensions, packing material, and particle sizes. 

Sample: 20 µL

1. 1.Sodium citrate 15 mM in H₂O