Excite Pharma Services offers residual solvent analysis programs for drug substances (APIs), drug products and excipients utilizing the U.S. Pharmacopeial Convention guideline (USP 467) for the design of its residual solvent studies. Individual customized programs are available.

Residual solvents are organic volatile impurities (OVIs) either used or produced during the manufacture of APIs (Active Pharmaceutical Ingredients), excipients and / or drug products. Residual solvent analysis is used to ensure pharmaceuticals are free from toxicologically significant levels of volatile organic compounds either left behind or created in the manufacturing process.

Residual solvent analysis is a very important QC procedure in the pharma industry. Sampling is typically performed by static headspace and analysis is done by GC/FID (flame ionization detector) using a dedicated column. GC/MS (mass spec) can also be used for residual solvent analysis.

There are 3 classes of solvents: Class 1, 2 and 3. Class 3 solvents have a low toxic potential to humans. No long-term toxicity or carcinogenicity data are available for many of these substances. Class 2 solvents are non-genotoxic animal carcinogens. Solvents in this class should be limited in pharmaceutical products because of their inherent toxicity. Class 1 solvents (carcinogens) are strongly suspected of being both harmful to humans and environmental hazards. If possible, they should be avoided or at the least have their levels controlled.

Testing of drug substances, excipients, and drug products for residual solvents should be performed when production or purification processes are known to result in the presence of such residual solvents. It is only necessary to test for residual solvents that are used or produced in the manufacture or purification processes.

If you have any questions or are interested in more details of our residual solvent analysis capabilities, please contact us.