Andrographolide is an important active ingredient from Chinese herb-Andrographis paniculate (Burm) Nees, which is required very high quality, especial purity, to develop new type injection. In order to separate and purify andrographolide in high efficiency, the author chooses extract of Andrographis paniculate (Burm) Nees as experimental material, investigating the mechanism of supercritical fluid extraction and crystallization, analyzing the influence factors; With HPLC (High perfomance liquid chromatograp...