Background:
At present, there were numerous researches on the migration of components in tablets and granules,
the investigation in the pharmaceutical literatrue concerning the effect of drying rate on the migration of water-soluble components of pellets was limited. Temperature and relative humidity (RH) were crucial parameters during the drying process
which was an essential step in the preparation of pellets via wet extrusion/spheronization. To quantify these variables, the
water loss percentage of pellets per minute was defined as drying rate.
Objective:
The study aimed to investigate the influence of drying rate on the migration of water-soluble components in wet
pellets and the potential migrated mechanism.
Methods:
The pellets containing tartrazine as a water-soluble model drug and microcrystalline cellulose as a matrix former
were prepared by extrusion/spheronization and dried at four different drying temperature and relative humidity. Afterward,
the extent of migrated tartrazine was assessed regarding appearance, in-vitro dissolution test, Differential Scanning Calorimetry, X-Ray Powder Diffraction, Attenuated total reflectance Fourier transform infrared spectroscopy and Confocal Raman Mapping.
Results:
Results demonstrated that red spots of tartrazine appeared on the surface of pellets and more than 40% tartrazine
were burst released within 5 minutes when pellets dried at 60℃/RH 10%. While pellets dried at 40℃/RH 80%, none of
these aforementioned phenomena was observed.
Conclusion:
In conclusion, the faster drying rate was, the more tartrazine migrated to the exterior of pellets. Adjusting drying temperature and relative humidity appropriately could inhibit the migration of water-soluble components within wet extrusion/spheronization pellets.
