Comparative evaluation of silicified microcrystalline cellulose II as a direct compression vehicle.

The powder flow and tableting properties of novel silicified microcrystalline cellulose II (SMCCII) were evaluated and compared with current silicified cellulosic I excipients such as ProSolv(®) SMCC50 and ProSolv(®) SMCC90. This excipient was prepared by coprocessing cellulose II and silicon dioxide (SiO(2)) at a 95:5 ratio by spray drying. The novel SMCCII yielded more benefits in terms of functionality as compared with the parent cellulose II material. SMCCII had higher bulk and tap densities, better powder packing ability, reduced porosity, increased surface area, and increased flowability. This silicified excipient had the highest brittleness behavior as given by the Heckel, Leuenberger and brittle fracture index analyses. The mechanical properties of SMCCII, such as toughness and Young's modulus were comparable to those of commercial products. SMCCII was the least sensitive material to magnesium stearate, and blending time or reprocessing did not affect its compactibility. It also provided for the fastest compact disintegration and release of griseofulvin. This new material has the potential for use as a direct compression excipient.