Multidimensional spatial triangular area as an index for the evaluation of the release-absorption correlation of multiple component traditional Chinese medicines

The paper is aimed to provide a novel index, named as multidimensional spatial triangular area, for the evaluation of the release–absorption correlation of multiple component traditional Chinese medicines (TCMs).  The applicability of the method was demonstrated by the example data.  The method and standard practice for evaluation of the release–absorption correlation for western medicines with single compound could not be applied to TCMs with multiple components.  The release percentage or absorption percentage of the multiple components for TCMs at the sampling time was a point in the multidimensional space.  The area of the triangle formed by the sequential three points represented the changing characteristics of the components’ release and absorption kinetics.  The side lengths of the triangle could be calculated from the spatial distances between each two of the sequential three points.  Then the triangle area could be obtained by the side lengths.  The in vitro release–in vivo absorption correlation of the multiple components could be represented by the correlation between the integrating values of the release triangle areas and that of the absorption triangle areas.  The results of the examples indicated that the multidimensional spatial triangular area method could treat the multiple components in a holistic way, in line with the holism of the TCMs.  Therefore, the multidimensional spatial triangular area method provided new methodology for the release–absorption correlation of the TCMs with multiple components.