Self-reference chemical profiling in the comprehensive dissolution test of herbal medicines

The power of chemical profiling in characterizing the samples' chemical pools has greatly raised the interests of phytomedicine researchers. Unfortunately, the semi-quantitative nature of chemical profiling retards its exploration into the dissolution test of herbal medicines, which is a crucial quantitative measure to evaluate and control the in vitro releasing properties as the prerequisite for biomembrane permeation of herbal constituents. Here, a method integrating chemical profiling approach and self-reference strategy is developed for the purpose of dissolution test of herbal medicines. The chromatographic fingerprints of the self-reference samples are translated by principal component analysis (PCA) into chemical profiles that highly correlate to their nominal gross concentrations in spite of the poor quantitative performances of some individual peaks. Pareto scaling previous to PCA selectively highlights the relative loadings of peaks with good quantitative performances. An example of ginkgo biloba tablets shows that this method is efficient to judge whether the detected constituents are simultaneously released or not, determine both the gross release and the respective dissolution rates of them, and rapidly screen the slowly released ones that may have potential clinical implications. This method has potentials to enable deep insight into the molecular diffusion and dissolution of complex herbal formulations, and open a new window to comprehensively consider the bioavailable properties of herbal medicines.