Effect of the molecular mobility of water adsorbed by disintegrants on storage-induced hydrolytic degradation of acetylsalicylic acid incorporated into tablets under humid conditions.

The purpose of this study was to investigate the effect of molecular mobility of water adsorbed by disintegrants on the hydrolytic degradation of active pharmaceutical ingredients (APIs). Fourteen different disintegrants were tested. First, powdered disintegrants were stored at conditions of 40 °C/75% relative humidity ("humid conditions") and their T relaxation times were measured by time-domain nuclear magnetic resonance for examination of the molecular mobility of water adsorbed by the disintegrant.