Objective To investigate the existing states of Panax notoginseng total saponins in complex solution systems and elucidate the micellar association behavior of total saponins based on their ultrafiltration separation characteristics. Methods A total saponins solution of P. notoginseng was used as the research subject, with notoginsenoside R₁ and ginsenoside Rg₁, Rb₁, Rd selected as representative analytes. Ultrafiltration rejection rate, permeation rate, and micellar compositional ratio were employed as evaluation indices to analyze how key parameters—including inorganic salt concentration, temperature, and saponin concentration—affect saponin molecular states and ultrafiltration behavior. Results Owing to their amphiphilic structures, the saponins readily form micelles in aqueous solution, and their ultrafiltration performance is regulated by multiple environmental factors. Inorganic salts modulate micellar stability through ionic effects and salting-out actions: the divalent anion SO₄²⁻ disrupts hydration layers and strengthens hydrophobic interactions, thereby promoting micelle formation and precipitation, with salting-out intensity ranked as Na₂SO₄ > MgSO₄ > KCl. Monovalent salts such as KCl facilitate micellar association at low concentrations via charge shielding, whereas high concentrations intensify salting-out. Dammarane-type saponins, particularly Rb₁ and Rd, showed higher participation in salt-induced micelles, indicating a structure-driven association preference. Increasing temperature enhances molecular motion, weakens hydrophobic interactions and intermolecular hydrogen bonding within micelles, thereby promoting micelle dissociation, increasing permeation rates, and reducing rejection. Elevating saponin concentration strengthens hydrophobic and aggregative interactions among solute molecules, facilitating micelle assembly. By fitting the relationship between ultrafiltration rejection and membrane pore size at different solute concentrations, the molecular weight of micelles at 90% rejection and the internal compositional ratio of characteristic saponins were estimated. The results showed that at 10—20 mg/mL, micelles mainly consisted of diol-type saponins, but their association degree remained limited at low concentrations. At 30—60 mg/mL, the micellar molecular mass increased markedly, indicating that higher solute concentrations promote the formation of hybrid micelles. Conclusion This study elucidates the mechanisms by which pharmaceutical processing parameters regulate the micellar structure and ultrafiltration efficiency of P. notoginseng total saponins, providing theoretical and practical guidance for quality control and purification process optimization in saponin‑based traditional Chinese medicine formulations.

Panax notoginseng total saponins  /  ultrafiltration  /  micelles  /  solution environment  /  rejection rate  /  permeability  /  association law  /  notoginsenoside R₁  /  ginsenoside  /  salting-out effect