1H-NMR assay of papaverine hydrochloride and formulations

Phytochem Anal. 2002 Nov-Dec;13(6):301-4. doi: 10.1002/pca.657.


A precise and specific 1H-NMR method has been developed for the assay of papaverine hydrochloride (1) as a bulk drug, as well as in tablet and injection dosage forms. The assay depends upon the integration of the 12 protons of the four methoxy groups of 1 relative to that of the three methyl protons of acetanilide (internal standard). In addition to the accurate quantitative determination of 1, the method provides a specific means of identifying 1 as well as detecting other alkaloids or impurities.

MeSH terms

  • Acetanilides / chemistry
  • Dosage Forms
  • Magnetic Resonance Spectroscopy / methods
  • Papaver / chemistry
  • Papaverine / chemistry*
  • Protons
  • Tablets / chemistry


  • Acetanilides
  • Dosage Forms
  • Protons
  • Tablets
  • Papaverine