Phosphite and phosphate in Pamidronate suppressed conductivity detection

Pamidronate is applied to treat osteoporosis by strengthening the bones. It is a bisphosphonate containing a primary amine group. Phosphite and phosphate are related compounds, which need to be quantified. USP requires the use of formic acid eluent with refractive index detection. But a standard IC procedure offers an alternative with better sensitivity. Phosphite and phosphate are analyzed with conductivity detection after sequential suppression.