Objective Based on a confined mass transfer mathematical model, this study aims to establish a quantitative analysis method for the existing states of matrine in the complex solution environment of traditional Chinese medicine (TCM), and elucidate the influence pattern of the compatibility ratio of Danshen (Salviae Miltiorrhizae Radix et Rhizoma, SMRR) and Kushen (Sophorae Flavescentis Radix, SFR) on its acid-base complexation reaction. Methods Based on the mass transfer differences of component states during nanofiltration (NF) and ultrafiltration (UF), the mass transfer coefficient of matrine was fitted taking the component transmission rate and membrane flux as evaluation indicators. Using the molecular and ionic monomer components as references, a quantitative calculation model for the existing states was constructed. The existing states of matrine in the SFR extract and the SMRR- SFR co-extract were fitted to analyze the occurrence patterns of acid-base complexation reactions under different solution environments. Results Coupling UF and NF enhanced the separation differences between the ionic and molecular states of matrine, thereby improving the accuracy of the quantitative calculation model for the ionic state. The correlation coefficients of the power function equations for quantitatively calculating the existing states of matrine were all greater than 0.97, indicating that the model was successfully established. The proportion of matrine in the molecular state was approximately 1.21%-1.91% in both the SFR extract and the co-extract. In the SFR extract, matrine existed as 36.90% in the ionic state and 61.98% in the associated state. After compatibility and extraction of SFR and SMRR, the existing form of matrine changed significantly. When the compatibility ratio of SMRR was low, the ionic state was dominant, with the increase in the proportion of SMRR, the ionic proportion of matrine gradually decreased from 66.73% to 45.83%, transforming into a complex-structured composite state, and the corresponding composite state proportion rose from 31.87% to 52.90%. Conclusion A quantitative calculation method for the existing states of matrine in different solution environments was successfully constructed, providing technical support for elucidating the states of components in complex solution environments.

mathematical model of confined mass transfer  /  existence state  /  matrine  /  salvianolic acid B  /  Salviae Miltiorrhizae Radix et Rhizoma  /  Sophorae Flavescentis Radix  /  formulation compatibility  /  nanofiltration  /  ultrafiltration  /  dynamic light scattering method  /  scanning electron microscopy