Synthesis and Altered Biodistribution of ^99mTc Labeled Vincristine in Animal Model

Introduction: Vincristine sulphate is an antineoplastic agent, used in combination for the chemotherapyof B-cell neoplasm and acute lymphoblastic leukemia. Our aim was to label the vincristine with 99mTc and study it's in vivo localization in animal model, so that in future we utilize it as potential imaging agent of colon. Materials and Methods: 2mg of vincristine using stannous chloride was labeled with ^99mTcO4. Its radiochemical purity was checked by instant layer chromatography using TLC/SG as a stationary phase and methanol: (diethyl-amine: water=1:9): 70:30and found 98.7% as complex. The time based study from 10 to 240 min. wasdone by acquiring anterior and posterior static images. Results: Organ versus blood Region of Interest (ROI) was drawn and time-activity graph was plotted. It was found that after 10min. 20.8% of total activity was localized in lungs, metabolized by liver, and excreted through gut. After 120 minutes, 29.3% of labeled drug was localized in colon and was execrated through gut. Its localization in lungs, retention in colon showed that it follows the same path as therapeutic vincristine sulphate. Conclusion: It was concluded that vincristine formed a stable complex with 99mTc, which can be used in further studies as an imaging agent of colon.