What is the role of alkaloid precipitation reaction in the study of chemical constituents of traditional Chinese medicine A: The pharmacological effects of traditional Chinese medicine are often the same result of multiple active components acting on different biological target molecules. Therefore, studying the interaction between chemical components of traditional Chinese medicine and biological target molecules at molecular level will not only help to clarify the mechanism and material basis of traditional Chinese medicine, but also provide meaningful guidance for the design and development of new drugs. In this paper, the key DNA sequence and calmodulin in the promoter of survivin gene were selected as tumor-related biological target molecules. The interaction between different chemical components of traditional Chinese medicine and two target molecules was studied by soft ionization mass spectrometry. The chemical constituents of 40 kinds of traditional Chinese medicines (including 13 alkaloids, 20 kinds of flavonoids and 7 kinds of ginsenoside) and double-stranded DNA were systematically studied by electrospray ionization mass spectrometry (ESI-MS) and tandem mass spectrometry (MS) ... The pharmacological effects of Chinese herbal medicines are often the same result of multiple active components acting on different biological target molecules. Therefore, studying the interaction between chemical components of traditional Chinese medicine and biological target molecules at molecular level will not only help to clarify the mechanism and material basis of traditional Chinese medicine, but also provide meaningful guidance for the design and development of new drugs. In this paper, the key DNA sequence and calmodulin in the promoter of survivin gene were selected as tumor-related biological target molecules. The interaction between different chemical components of traditional Chinese medicine and two target molecules was studied by soft ionization mass spectrometry. The interaction between 40 chemical components of traditional Chinese medicine (including 13 alkaloids, 20 flavonoids and 7 ginsenoside) and double-stranded DNA target molecules was studied by positive and negative ion electrospray ionization mass spectrometry and tandem mass spectrometry. The relative binding strength of different chemical components of traditional Chinese medicine with double-stranded DNA target molecules was calculated and compared, and their structure-activity relationship was clarified. By studying the interaction between alkaloid components and double-stranded DNA target molecules, the interaction between three alkaloids (reserpine, berbamine and tetrandrine) and DNA molecules was discovered for the first time. Through the study on the interaction between flavonoids and ginsenoside and double-stranded DNA target molecules, it is found that the binding strength between drugs and DNA target molecules is closely related to the type of aglycone, the structure and position of glycogen. The interaction between chemical components in two kinds of flavonoids extracts from traditional Chinese medicines with anti-tumor activity and double-stranded DNA target molecules was studied by centrifugal ultrafiltration-high performance liquid chromatography-tandem mass spectrometry (CUF-HPLC-MSn), and seven flavonoids bound to DNA target molecules were screened out, and their structures were identified by tandem mass spectrometry. The intensity attenuation MALDI-MS is introduced into the study of the interaction between ligand molecules and protein for the first time. The interaction between calmodulin and peptides, phenothiazine drugs and alkaloids of traditional Chinese medicine was studied by this method, and the relative binding strength of different ligands with calmodulin was compared by titration experiment and competitive reaction. This paper fully proves the application prospect of soft ionization mass spectrometry in detecting the interaction between chemical components of traditional Chinese medicine and biological target molecules. The research results can not only provide experimental reference for clarifying the anti-tumor effects of chemical components and extracts of traditional Chinese medicine, but also provide a fast, sensitive and powerful soft ionization mass spectrometry technology platform for further screening active components of traditional Chinese medicine. Pack more things.