188W/188Re GENERATOR – INVESTIGATION OF LONG TERM STABILITY

摘要

The rhenium-188 (T1/2 = 16,98 h) is a beta-gamma emitting radionuclide (average energy of β-rnparticles - 764 keV) suitable for therapeutical application. The gamma emission of 188Re (155 keV) allowsrnevaluation of biodistribution of 188Re labelled radiopharmaceuticals and is useful in radiation dosimetry study.rn188Re is produced in decay of 188W followed by the chromatographic separation. The production of 188Re at therncentralized laboratory needs handling of large amounts of activity to overcome the loss of activity during isotopernproduction and transportation to the end user. The aim of this work was to develop a 188W/188Re portablerngenerator using high specific activity 188W and the available design of generator column. In this paper we presentrnresults of the long term stability study of 188W/188Re generator developed in our laboratory. The generatorrncolumn containing alumina was first activated by washing with a set of solutions. The radioactivities of about 5.5rnGBq of 188W (195 GBq/g W) in the form of tungstenic acid were loaded on the column (flow 0.1 ml/min). Afterrn188W deposition the alumina column was washed with 0.9% NaCl solution (pH = 5.0 – 6.0). Each of thernmanufactured generators was eluted 2-3 times per week over the period of up to 9 months. The elution yield, thernradionuclidic purity, the radiochemical purity and chemical purity of the eluted 188Re-perrhenate solution wererntested in each of the elutions. Bacterial endotoxines test and sterility test were performed at the production daternand at 2 months intervals. The results of our study show that the generators can be eluted with high, over 75%rnelution yield. No changes in quality of eluates were observed over the time of their examination, proving theirrnstable performance.