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Objective: To label the Arg-Gly-Asp containing peptide RGD which specificly bind with αvβ3 receptor expressed in tumor angiogenesis by pertechnetate, and evaluate its biodistribution in human lung adenocarcinoma bearing mice.Methods: 1.99Tcm-hydrazino-nicotinamide (HYNIC)c(RGDfK) was prepared by two-steps method with tricine and ethylenediamine diacetate(EDDA) as coligands, and HYNIC as dual functional chelator.The bioactivity of 99Tcm-HYNIC-c(RGDfK) was measured by competitive receptor binding assay.2.Human A549 lung adenocarcinoma bearing mice were randomly divided into seven groups, 5 mice for each group.The control group was blocked by 100μg unlabeled HYNIC-c(RGDfK) half an hour before injecting 99Tcm-HYNIC-c(RGDfK).The imaging was obtained at 0.5,1,2,4,8 and 12h respectively after intravenous injection of 7.4 MBq 99Tcm-HYNIC-c(RGDfK).The biodistribution and tumor/muscle (T/NT) value was calculated by the region of interest (ROI) technique and %ID/g technique (percentage activity of injection dose per gram of tissue).3.Finally, SPECT static imaging of 3 mice was obtained at 1、 2、 4、 8、 12h after intravenous injection of 99Tcm-HYNIC-c(RGDfK) respectively.Results: The labeling yield of 99Tcm-HYNIC-c(RGDfK) was more than 90% with the radiochemical purity more than 95%.99Tcm-HYNIC-c(RGDfK) can specificly bind with A549 adenocarcinoma cell with a maximum binding rate of 36%.The 99Tcm-HYNIC-c(RGDfK) in kidney is consistently higher than 20%.Its uptake by tumors at 0.5h was 10.52±1.48, the highest uptake is 17.26±2.81 at 8h, and still remain 8.93±0.90 at 12h.While the tumor uptake of 99Tcm-HYNIC-c(RGDfK) significantly decreased to 2.29±0.85 when it was blocked by unlabeled HYNIC-c(RGDfK).The uptake of 99Tcm-HYNIC-c(RGDfK) were continuously decreased in other organs and tissues, resulted a highest T/NT up to 6.87 measured by ROI.Xenografted tumors started to be imaged at 1h and getting more clearly between 4 and 8h after injection of 99Tcm-HYNIC-c(RGDfK).Condusion: HYNIC-c(RGDfK) can be efficiently labeled by pertechnetate with a reasonable radiochemical characteristics and favorable imaging property.It should be a potential radiotracer in targeted therapy in integrin αvβ3 positive tumor.