Preparation, distribution, stability and tumor imaging properties of [62 Zn] bleomycin complex in normal and tumor - bearing mice

Bleomycin [BLM] has been labeled with radioisotopes and widely used in therapy and diagnosis. In this study BLM was labeled with [62Zn] zinc chloride for oncologic PET studies. The complex was obtained at the pH=2 in normal saline at 90°C in 60 min. Radio-TLC showed an overall radiochemical yield of 95-97% [radiochemical purity > 97%]. Stability of complex was checked in vitro in mice and human plasma/urine. Preliminary in vivo studies performed to determine complex stability and distribution of [62Zn] BLM in normal and fibrosarcoma-bearing mice. [62Zn] BLM accumulated significantly in induced fibrosarcoma tumors in mice according to bio-distribution/imaging studies. [62Zn] BLM can be used in PET oncology studies due to its suitable physico-chemical properties as a diagnostic complex in vitro and in vivo. Further studies should be performed for evaluation of the complex behavior in higher animals

Production of Ga-67 in Iran

The radioisotope 67Ga [T 1/2=78 h] in extensively used as single photon marker for detecting the presence of malignancy and the diagnosis of inflammatory diseases. The high tumor specificity of carrier-free 67Ga make it one of the most interesting radionuclides in nuclear medicine for in vivo scanning studies. 67Ga is a cyclotron produced radioisotopes and is one of the radiopharmaceuticals which is produced at our center. An enriched 68Zn cyclotron target design has been developed for the large-scale production of carrier-free 67Ga with -<5 percent 66Ga contamination as one of the impurities. The advantage of high 67Ga yield from proton beam bombardment of enriched Zinc is somewhat to our disadvantage due to the high price of enriched Zinc. Due to this problem another alternative method for Ga-67 production was sought. Our theoritical and experimental studies have been resulted to production of 67Ga by irradiating natural Zinc with deuteron beam. The production of the radiopharmaceutical is achieved by two steps. 1] Deuteron bombardment of natural Zinc target in the cyclotron and subsequent production of Ga-67. 2] Chemical processing which involves the separation of 67Ga from target material. After quality control testing, the produced 67GaCI3 is converted to citrate and as a sterile and pyrogen free product, it is ready for human use