Objective To investigate the anticancer mechanism of Herba Hedyotis Diffusae on PG cell by observing the action of Herba Hedyotis Diffusae in inducing apoptosis of PG cells. Method After treating PG cells with different doses of drug containing serum of Herba Hedyotis Diffusae, FCM was used to detect the apoptosis of PG cell. Result After treating PG cell with Herba Hedyotis Diffusae, typical apoptosis characteristics could be seen and apoptosis rates were increased with the relation of dosage-effect, which were 6.86%, 9.77% and 11.69%, respectively. Conclusion Inducing the apoptosis of tumor cells maybe part of the anti-tumor mechanism of Herba Hedyotis Diffusae.

There are three types of bioanalytical methods for nucleic acid drugs， including ligand binding assay， quantitative polymerase chain reaction and liquid chromatography-based bioanalytical technologies. Although the first two assays have high sensitivity， they have poor selectivity and can not differentiate between intact and truncated metabolites. Liquid chromatography- based bioanalytical technologies which are less sensitive， offer high selectivity for the identification of intact and truncated metabolites. They have broad application prospects in both preclinical and clinical investigations of therapeutic nucleic acid drugs. This paper provides a critical review on the characteristics of these technologies and their application to analyze nucleic acid drugs， including high performance liquid chromatography-ultraviolet detection （HPLC-UV）， high performance liquid chromatography- fluorescence （HPLC-FL）， liquid chromatography-tandem mass spectrometry （LC-MS/MS）， liquid chromatography-high resolution- mass spectrometry， microflow liquid chromatography-tandem mass spectrometry （microflow LC-MS/MS） and hybridization liquid chromatography-tandem mass spectrometry. Although these technologies have high sensitivity except for HPLC-UV， they still have some shortcomings， such as suitable probes need to be designed for HPLC-FL， standard substance for LC-MS/MS， and high cost for microflow LC-MS/MS. In addition， the development of some related strategies or technologies （e.g. non-specific adsorption strategy， sample pretreatment） which can improve the sensitivity， has hastened the development of liquid chromatography-based bioanalytical technologies for nucleic acid drugs.