Evaluation of hydroperoxides in common pharmaceutical excipients.

While the physical properties of pharmaceutical excipients have been well characterized, impurities that may influence the chemical stability of formulated drug product have not been well studied. In this work, the hydroperoxide (HPO) impurity levels of common pharmaceutical excipients are measured and presented for both soluble and insoluble excipients. Povidone, polysorbate 80 (PS80), polyethylene glycol (PEG) 400, and hydroxypropyl cellulose (HPC) were found to contain substantial concentrations of HPOs with significant lot-to-lot and manufacturer-to-manufacturer variation.