Potassium analysis using ion chromatography according to USP test methods

Potassium analysis using ion chromatography according to USP test methods

In 2010, the United States Pharmacopeia (USP) began modernizing its monographs[1]. As part of this effort, testing methods to quantify potassium now include ion chromatography. Ion chromatography is a viable alternative method for analyzing potassium. Compared to other potassium analysis methods, ion chromatography has the advantage of analyzing multiple cationic species at the same time.

Potassium is important for nerve transmission, muscle contraction, fluid balance, blood pressure and more. Low potassium levels (hypokalemia) can cause cramps, constipation, or even heart failure. Mild or moderate hypokalemia can be treated with potassium tablets or intravenous potassium infusion[2].

It is important to determine both the potassium content and possible contaminants in these products. Pharmaceutical manufacturers and laboratories must follow guidelines in USP monographs for testing drugs and dietary supplements.

As part of its modernization effort[1]The USP has updated several monographs to include ion chromatography (IC) as an analytical method for potassium. The USP now proposes IC as an alternative to the traditional methods of atomic absorption spectroscopy (AAS) and flame photometry.

AAS and flame photometry are based on measuring the characteristic emission or absorption spectra of atoms in a flame. These methods require flammable gases and expensive equipment. IC is able to separate and quantify ions in a solution into a stationary phase based on their different affinities. This allows IC to measure multiple analytes in a single run, increasing its efficiency and versatility.

With IC, manual matrix removal steps are not required because high capacity columns provide excellent separation even in samples with a heavy matrix load. For example, IC can simultaneously determine the potassium content and possible contaminants such as sodium and ammonium in a pharmaceutical product or dietary supplement.

The updated USP monographs for potassium analysis use a separation column with L76 packaging, like theMetrosep C 6 – 150/4.0. This column is optimized to separate cations with large concentration differences. Read the following application notes to learn more about potassium analysis using ion chromatography according to USP. All methods presented have been validated according to the USP General Chapters <1225> Validation of Compendia Procedures[3] and <621> Chromatography[4].

Discover more:

• ANWENDUNG HINWEIS: Kalium in Kaliumbicarbonat -Sprudelabletten für orale Lösung
• Anwendung Hinweis: Kalium- und Natriumbicarbonate und Zitronensäure -Sprudel -Tabletten für orale Lösung
• ANWENDUNG HINWEIS: Kalium in Kaliumbicarbonat- und Kaliumchlorid -Sprudelabletten für orale Lösung

To learn more about the use of ion chromatography in various USP testing methods, visit Metrohm's website, "Drug Monographs, Assays and Impurity Assessments Using Metrohm Ion Chromatography."

References

[1] Santos, L.M.; Davani, b.; Anthony, CM; Clark, JE USP -Monograph -Modernization Initiative. 2024-05-01).

[2] Kardalas, E.; Paschou, SA; Anagnostis, P.; Muscogiuri, G.; Siasos, G.; Vryonidou, A. Hypokalemia: A clinical update. Endocrine Compounds 2018, 7 (4), R135 – R146.

[3] US Pharmacopeia. USP-NF. 〈1225〉 Validation of compendium procedures.

[4] US Pharmacopeia. USP-NF. 〈621〉 Chromatography.

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