Abstract
Objective: This article investigated the structural characteristics, powder properties, and performance variations of co-processed pregelatinized starch (PS) and microcrystalline cellulose (MCC) at varying ratios. Methods: Scanning Electron Microscopy (SEM) revealed the embedding of MCC within the PS matrix. Fourier-transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) analysis indicated no chemical interaction between the starch and MCC during processing. The physical properties of the co-processed materials were evaluated using multiple indicators, such as the Carr index, and their properties in pharmaceutical applications were evaluated using multiple indicators, such as tensile strength and dilution capacity. Results:The absence of new chemical substances during co-processing, as confirmed by FTIR/XRD analyses, coupled with SEM evidence of a physically interlocked MCC-PS architecture, conclusively demonstrates that structural reorganization occurred via physical mechanisms.An increase in the MCC proportion enhanced the tensile strength of the co-processed material while decreasing the Carr's index, particle size, tapped density, bulk density, swelling, and water-soluble content. A co-processed sample (PS:MCC = 7:3) was selected for application in formulations. The co-processed material exhibited superior compactibility compared to a physical mixture and demonstrated favorable dilution capacity in poorly compactible model drugs, including Linaoxin and Lingzhi spore powder, as well as higher biological inertness. Conclusions: These findings suggest that the co-processed PS and MCC possess excellent compactibility and dilution capacity. The co-processed excipient demonstrates applicability in direct compression manufacturing of oral solid dosage forms (e.g., tablets), offering distinct advantages for high drug-loading formulations.