Efficient analysis of pharmaceutical drug substances and products using a solid-state NMR CryoProbe

Analyst. 2023 Feb 13;148(4):724-734. doi: 10.1039/d2an01903e.

Abstract

Solid-state nuclear magnetic resonance (ssNMR) is a high-resolution and versatile spectroscopic tool for characterizing pharmaceutical solids. However, the inherent low sensitivity of NMR remains a significant challenge in the analysis of natural abundance drug substances and products. Here, we report, for the first time, the application of a CPMAS CryoProbe™ to improve the sensitivity of 13C and 15N detection by approximately 5 to 6 times for solid-state analysis of a commercial pharmaceutical drug posaconazole (POSA). The sensitivity enhancement enables two-dimensional (2D) 13C-13C and 1H-15N correlation experiments, which are otherwise time-prohibitive using regular MAS probes, for resonance assignment and structural elucidation. These polarization transfer and correlation experiments reveal drug-drug and drug-polymer interactions in amorphous POSA and its amorphous solid dispersion formulation. Our results demonstrated that the CPMAS CryoProbe™ can be widely applied for routine pharmaceutical analysis and advanced structural investigations with significantly enhanced efficiency and throughput.

MeSH terms

  • Magnetic Resonance Imaging*
  • Magnetic Resonance Spectroscopy / methods
  • Pharmaceutical Preparations

Substances

  • Pharmaceutical Preparations