Objective This study focused on the concentration process in the manufacturing of Guizhi Fuling Capsules (GFC, 桂枝茯苓胶囊). By analyzing the correlations among effective components, physical properties, and process parameters, it aimed to identify critical quality attributes (CQAs) and critical process parameters (CPPs), explore quality control indicators and their acceptable ranges, and assess the potential for using physical properties of intermediate to guide its quality control. Methods The variations in process parameters (temperature, relative density at endpoint), physical properties (particle size, polydispersity index, ζ potential, conductivity, pH value, viscosity and refractive index), and effective components and total solid content during the concentration process were systematically investigated. Chemometric methods, including Pearson correlation coefficient, grey relational analysis, and partial least squares regression, were applied. Linear models between effective components and physical properties under different process parameters were established to elucidate the correlations among them. Results Analysis of effective component content and physical properties revealed strong correlations between effective components and ζ potential, conductivity, viscosity, and total solids content. For instance, viscosity was positively correlated with total solids, and the contents of amygdalin and paeoniflorin were both positively correlated with total solid content. Analysis of the active ingredients and physical property parameters of samples under various process parameters revealed that the concentration temperature is a key factor influencing the correlation between active ingredients and physical property parameters. Conclusion Correlation analysis of process parameters, physical properties, and effective components revealed interactive and dynamically linked relationships among these variables. Precise control of the concentration temperature during the manufacturing is essential to improve the quality and batch-to-batch consistency of the extract. To a certain extent, parameters such as viscosity, relative density, refractive index and pH value can reflect the quality of intermediates during concentration, providing a reference for the development of online intelligent monitoring in the concentration process of traditional Chinese medicine extracts.

Guizhi Fuling Capsules  /  effective components  /  physical properties  /  process parameters  /  concentration process  /  correlation analysis  /  amygdalin  /  paeoniflorin