This analytical note highlights a selective and sensitive procedure for determining Nitrite and Nitrate in Lactose by ion chromatography. Although nitrite present in excipients poses a significant risk for the formation of nitrosamine, nitrate is also added to establish the specificity of the method during the validation.
- LOQ – 0.2 μg/g for for Nitrite and 0.4 μg/g for Nitrate with respect to 25 mg/g sample concentration.
- Validated Range – 0.2 μg/g—20 μg/g for Nitrite and 0.4 μg/g—40 μg/g for Nitrate with respect to 25 mg/mL sample concentration.
- Precision – Using a conductivity detector, the %RSD of Nitrite and Nitrate of the 6 recoveries at LOQ levels were 2.11 and 7.18, respectively. Using a UV detector, the %RSD of the 6 results for Nitrite and Nitrate were 4.95 and 6.91
respectively. - Accuracy – %Recovery for nitrite and nitrate using both the conductivity and UV detectors were within 100 ± 30.0%.
USP App not - Determination of Nitrite and Nitrate in Lactose by IC.pdf (1.0 MB)
Disclaimer
This application note was developed to provide an analytical resource for regulators and industry to monitor nitrosamine impurities in drug products, drug substances or other matrices. It is intended to serve as a resource for informational purposes only and not as an USP-NF compendial documentary standard. This document was developed by USP staff without a public comment period and does not reflect USP or USP’s Expert Body opinions on future revisions to official text of the USP-NF. Parties relying on the information in this document bear independent responsibility for awareness of, and compliance with, any applicable federal, state, or local laws and requirements.
This is USP’s first non-compendial method published in Analytical hub for determination of Nitrite and Nitrate in Lactose. We will be posting more such methods for several at-risk excipients. This method can be used to establish level of nitrites/ nitrates in excipients and study lot to lot variability. It is intended to serve as a resource for informational purposes only and not as an USP-NF compendial documentary standard. Users will have to verify suitability of this procedure for intended purpose