AN238: Determination of Sulfate and Sulfamate in Topiramate Using a Reagent-Free Ion Chromatography System
DescriptionIn this application note (AN), we demonstrate the use of a Reagent-Free™ Ion Chromatography (IC) system with the IonPac® AS11 column and suppressed conductivity detection for the determination of sulfamate and sulfate in topiramate. The IonPac AS11 column has been successfully used in the pharmaceutical industry and is currently specified in several USP methods, including an assay for citric acid/citrate and phosphate in different pharmaceutical formulations, phosphite in etidronate disodium, and free sulfate in enoxaparin sodium injection. The IonPac AS11 column consists of a 13 μm microporous resin bead with a highly crosslinked core, and a MicroBead® anion-exchange layer that is functionalized with hydrophilic quaternary ammonium groups. The selectivity of the AS11 column is optimized for the separation of a large number of inorganic anions and organic acid anions using a hydroxide eluent gradient. Because the selectivity of sulfamate is similar to low molecular weight organic acids, the AS11 column is ideal for this application. The column enables the resolution of the target analyte from other excipients in a topiramate sample while also allowing the separation of sulfate within a reasonable time. An automated potassium hydroxide eluent generator eliminates the problems typically encountered when manually preparing hydroxide eluents, as described in the current USP method. In addition, no organic solvents are required, which further simplifies this analysis. In this application note, the linearity, detection limits, precision, and recovery of the sulfamate and sulfate degradation products in a topiramate sample are demonstrated.
For Research Use Only. Not for use in diagnostic procedures.