From particle to performance: Linking size-dependent swelling to disintegration mechanisms in natural plant product...

Particle size is a critical powder attribute affecting tablet disintegration, yet its underlying mechanism remains insufficiently elucidated. This study systematically investigates the role of particle size in regulating the disintegration behavior and mechanism of Natural Plant Product (NPP) tablets. NPP powders with different particle size distributions were prepared and characterized, which were subsequently compressed into tablets. Disintegration kinetics were quantitatively evaluated using stress relaxation method, while the dynamic disintegration process was visually captured through optical microscopy. K-means clustering analysis was employed to objectively classify disintegration modes based on the kinetic profiles. The results indicate that particle size governs swelling behavior during disintegration by affecting tensile strength and pore structure. Notably, larger particles were found to induce more pronounced swelling, which in turn facilitated faster and more complete disintegration. Furthermore, variations in particle size could alter the predominant disintegration mechanism. This work provides a particle-level perspective on the disintegration dynamics of NPP tablets, offering mechanistic insights that bridge raw material properties and dosage form performance.