Preparation, quality control and biodistribution of [^61Cu]-doxorubicin for PET imaging

This work was conducted for radiolabeling of an anticancer antibiotic, i.e. doxorubicin with 61Cu for pro-duction of possible tracer used in PET oncology. 61Cu was prepared with natural zinc target and 22 MeV150 mA pro-tons via natZn(p, xn)61Cu reaction with a yield of 123.2 MBq·μA-1·h-1. Optimization reactions were performed for pH, temperature and concentration. Biodistribution of the tracer was studied in normal and fibrosarcoma bearing mice. At the optimized conditions, ITLC showed that radiochemical purity was over 97% with a specific activity of 2.22×103MBq ·mmol-1·L-1. This was kept unchanged even with presence of human serum as well as room temperature for 5 h. Biodistribution of the tracer in fibrosarcoma bearing mice demonstrated significant tumor uptake after 2 h. This tracer can be used in the detection of various tumors responding to doxorubicin chemotherapy using PET scan and/or determination of tumor therapy response to doxorubicin chemotherapy.