Study on Lutetium-177 Labelled With Dotanoc Peptide for Cancer Theragnostic

A study of Lutetium-177 (Lu-177) labelled with DOTANOC peptide was carried out for targeted cancer theragnostic. 5 mg high enrich Lu₂O₃ was weighed and put in a quartz ampoule container. 50 μl 1M of hydrochloric acid was added to dissolve Lu₂O₃. Then the quartz ampoule container was dried in the oven. The quartz ampoule container containing the sample that has been dried next goes through a sealing process. After sealed, the target was then placed in a sealed aluminium can and irradiated in the dry-tube (DT) irradiation facility at one of the in-core position at the TRIGA PUSPATI Reactor (RTP) for 18 hours. The target was irradiated at neutron flux estimated about 0.6 x 10¹³ n.cm^-2.s^-1 to produce Lu-177 radioisotope. Lu-177 was then labelled with DOTANOC peptide and purified. The results showed that the labelled product is dissolved instantly with the solution is clear and colourless, and the pH is around 5.5. The labelling yield was found to be greater than 99.5±0.05 percent. Stability Study of ¹⁷⁷Lu-DOTANOC showed that the percentage of RCP is more than 99.5 % after 168 hours of incubation time at room temperature. For Serum Stability Test, more than 98 % ¹⁷⁷Lu-DOTANOC still remain intact after 168 hours of incubation time at 37 degree Celcius. ¹⁷⁷Lu samples have passed both sterility and bacterial endotoxin test. No sign of microbial growth as well as bacterial endotoxin content was detected. Further validation tests need to be conducted to confirm that ¹⁷⁷Lu is safe to be use. (author)