Effect of the type of lubricant on the characteristics of orally disintegrating tablets manufactured using the phase transition of sugar alcohol.

The aim of this study was to evaluate the effect of lubricants on the characteristics of orally disintegrating (OD) tablets manufactured using the phase transition of sugar alcohol. OD tablets were produced by directly compressing a mixture containing lactose-xylitol granules, disintegrant, glidant and lubricant, and subsequent heating. The effect of the type of lubricant on the tablet characteristics was evaluated using magnesium stearate (Mg-St), sodium stearyl fumarate (SSF), and talc as lubricants. The hardness of the tablets increased to ca. 6kp as a result of heating, regardless of the kind of lubricant. The oral disintegration time of the tablets containing Mg-St or SSF increased with an increase in the hardness. In contrast, the oral disintegration time of the tablets containing talc was not changed despite of an increase in hardness. The water absorption rate of the tablets containing talc was much faster than that of the tablets containing other lubricants. The surface free energy measurement showed that the polarity of the tablet components containing talc was remarkably increased by heating. The water absorption rate of the tablets containing talc was also increased by heating. These results indicate that a more hydrophilic surface might be attained by heating the talc. Consequently, talc was demonstrated to be the most desirable lubricant for the preparation of OD tablets based on the principle of the phase transition of sugar alcohol.