Objective: To investigate the contents after single oral one kind of homogeneous molecular weight polysaccharide(MDG-1) extracted from Ophiopogonis Radix in rat urine and faeces by high performance gel permeation chromatography(HPGPC). Method: Labeling the MDG-1(F-MDG-1) and detecting replacement of fluorescein isothiocyanate(FITC) then the HPGPC was used to detect the contents of MDG-1 in urine and faeces after single oral administration. The rats were given F-MDG-1 at doses of 300 mg·kg-1 then urine and faeces were collected at predefined time points (0

4

12

24

48

72 h postdose;n=six per time point) then stored at -20 ℃ to be analyzed. Result: The F-MDG-1 in rats urine was described with the max 0.808 7 mg at 12 h and a degradation model to the lowest 0.1053 mg at 72 h. The F-MDG-1 in rats faeces was described with the max 21.332 4 mg in 12 h and a degradation model to the lowest 0.506 5 mg at 72 h. Conclusion: The combination of the FITC prelabeling method with the HPGPC is confirmed and tested and feasibile.This methodology should be helpful to other polysaccharides research in rat urine and faeces. In this study

F-MDG-1 was absorbed hardly and the main excretion way is through faeces.