Silicified microcrystalline cellulose is a synergistic, intimate physical mixture of two components: microcrystalline cellulose and colloidal silicon dioxide. Silicified microcrystalline cellulose contains MCC up to 98% and 2% w/w colloidal silicon dioxide.

Silicification of the microcrystalline cellulose is achieved by a process, resulting in an intimate association between the colloidal silicon dioxide and microcrystalline cellulose. SMCC combines the excellent compactibility of microcrystalline cellulose with superior flow properties. Therefore, it is ideally suited to direct compression formulations where it has advantages in both flow and compactibility. It also exhibits both brittle fracture and plastic deformation characteristics, leading to superior binding properties.