NMR Relaxometry to Characterize the Drug Structural Phase in a Porous Construct

Abstract

Nuclear magnetic resonance (NMR) frequency spectra and T2 relaxation time measurements, using a high-power radio frequency probe, are shown to characterize the presence of an amorphous drug in a porous silica construct. The results indicate the ability of non-solid-state NMR methods to characterize crystalline and amorphous solid structural phases in drugs. Two-dimensional T1–T2 magnetic relaxation time correlation experiments are shown to monitor the impact of relative humidity on the drug in a porous silica tablet.