A simple method for the identification and assay of iopamidol and iothalamate meglumine in pharmaceutical samples based on proton nuclear magnetic resonance spectroscopy.
A proton nuclear magnetic resonance (PMR) spectroscopic method is described for the direct assay and identification of the triiodinated radiographic contrast agents iopamidol (nonionic type) and iothalamate meglumine (ionic type) in commercial solutions and as a bulk material. Samples were prepared by simply diluting an injectable solution with or dissolving a powdered sample in D2O. Sodium acetate was added to serve as an internal standard. Quantitations were based on the resonance signals for the protons of the CH3-CO-group at 1.58 ppm (iopamidol) or 2.25 ppm (iothalamate), CH3-N-group at 2.38 ppm (meglumine) and CH3-CO-group at 1.92 ppm (acetate). The mean +/- SD (n = sets of 10 samples each) recovery of iopamidol, iothalamic acid and meglumine from synthetic mixtures with the internal standard were 99.6 +/- 0.63, 99.7 +/- 0.66 and 99.9 +/- 1.18%, respectively; with the values ranging from 98.7-100.9% for iopamidol and iothalamate, and from 98.3-100.8% for meglumine.
Department of Health and Human Services, Northeast Regional Laboratory, Food and Drug Administration, Jamaica, New York, New York, USA.
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Hanna
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Lau-Cam
D003287:Contrast Media / Q000032:analysis*; D017666:Deuterium Oxide; D007479:Iopamidol / Q000032:analysis*; D007482:Iothalamate Meglumine / Q000032:analysis*; D009682:Magnetic Resonance Spectroscopy; D019999:Pharmaceutical Solutions; D012015:Reference Standards
D003287:Contrast Media; D019999:Pharmaceutical Solutions; D017666:Deuterium Oxide; D007479:Iopamidol; D007482:Iothalamate Meglumine