SUNNYVALE, Calif. (Nov 2011) — Thermo Fisher Scientific Inc. is pleased to announce a new method that exceeds the U.S. Pharmacopeia (USP) monograph specifications for risedronate sodium analysis. This method is based on an anion-exchange separation with a 4 × 250 mm Thermo Scientific Dionex IonPac AS7 (USP L48) column using edetate disodium (EDTA) eluent to resolve risedronate from related compounds. Application Note 289: Evaluation of the USP Risedronate Sodium Assay demonstrates the linearity, detection limits, precision, and accuracy of the assayed amount of risedronate in the drug substance and drug product (Actonel, 35 mg tablets). The results of this study show the method to be simple, rugged, and accurate, thus making it suitable for use by quality control labs to ensure that the drug meets approved specifications.

The test results of this new method meet or exceed the USP monograph specifications for each tested variable in the range. The method separates risedronate in

This application note and many others can be found at www.thermoscientific.com/dionex under the Documents tab.