The invention relates to the technical field of preparative liquid
chromatography separation, and particularly discloses a two-dimensional high-pressure preparative liquid
chromatography system and a separation and purification method for low-content target components in a
medicine. The
system comprises a first-dimensional high-pressure preparative liquid
chromatography system, a two-position six-way switching valve, a multi-position selection valve, a
trapping column and a second-dimensional high-pressure preparative liquid chromatography system, the second-dimensional high-pressure preparative liquid chromatography system comprises a second mixer and a two-dimensional
separation column; the first-dimensional high-pressure preparative liquid chromatography system is sequentially communicated with the two-position six-way switching valve, the multi-position selection valve and the
trapping column, and the outlet end of the
trapping column is communicated with the two-position six-way switching valve again; and the second mixer is sequentially communicated with the two-position six-way switching valve and the two-dimensional
separation column. The method comprises the following steps: detecting a sample by using a one-dimensional system, and trapping a target component to a trapping column; and switching the two-position six-way switching valve, back-washing out captured components, and carrying out two-dimensional detection. The method disclosed by the invention has the
advantage of efficiently separating and purifying
impurity components with extremely low content in the
medicine.