Objective: To study microcrystalline cellulose II (MCCII) as new pelletization aid for a high and low solubility drugs such as verapamil. HCl and carbamazepine, respectively.
Methods:Approximately, 30 g of MCCII and drug mixtures were hydrated, passed through a # 20 mesh sieved and spheronizated at a frequency of 6 Hz and residence time of 480 s. A microscopy analysis was used to evaluate the shape and size descriptors. Pellets properties such as compressibility, friability, density, flowability and product yield were also evaluated. Drug release properties were tested according to the USP specifications and compared to those of MCCI.
Results:The wetting level of the excipients depended on drug loading and drug solubility. Thus, a high drug loading (>50%) rendered pellets having a low yield, flowability and caused a detriment on size descriptors. Likewise, the regular morphology and strength of MCCII-based pellets was highly affected by increasing drug loads. Verapamil. HCl pellets were less friable and compressible and showed better flowability than carbamazepine pellets. Regardless of drug loading and drug solubility, MCCII-based pellets released more than 80% of verapamil. HCl within 10 min, whereas released more than 75% of carbamazepine within 15 min. Conversely, MCCI pellets had a satisfactory verapamil. HCl release, but ~30% carbamazepine release within 1h.
Conclusion:MCCII proved to be a better excipient than MCCI to yield beads having optimal pellet characteristics, and rendered an immediate release profile for verapamil. HCl and carbamazepine.