Affiliation:
1. Division of Complex Drug Analysis, Office of Testing and Research, Office of Pharmaceutical Quality, Center for Drug Evaluation and Research U.S. Food and Drug Administration Silver Spring Maryland USA
2. Department of Chemistry and Biochemistry Texas Christian University Fort Worth Texas USA
3. Department of Chemistry and Biochemistry University of Maryland College Park Maryland USA
Abstract
AbstractOctreotide acetate, the active pharmaceutical ingredient in the long‐acting release (LAR) drug product Sandostatin®, is a cyclic octapeptide that mimics the naturally occurring somatostatin peptide hormone. Modern NMR can be a robust analytical method to identify and quantify octreotide molecules. Previous 1H chemical shift assignments were mostly performed in organic solvents, and no assignments for heteronuclear 13C, 15N, and aromatic 1H nuclei are available. Here, using state‐of‐the‐art 1D and 2D homo‐ and heteronuclear NMR experiments, octreotide was fully assigned, including water exchangeable amide protons, in aqueous buffer except for 13CO and 15NH of F1, 15NH of C2, and 15NζHζ of K5 that were not observed because of water exchange or conformational exchange. The solution NMR spectra were then directly compared with 1D 1H/13C/15N solid‐state NMR (SSNMR) spectra showing the potential applicability of 13C/15N SSNMR for octreotide drug product characterization.
Funder
National Science Foundation