A novel method of separation of 99mTc from (n, {gamma}) 99Mo of low/medium specific activity based on solid phase column extraction technique: Suitablity for use in diagnostic radiopharmaceuticals

1885 Objectives 99mTc is commonly available by eluting alumina column pre-absorbed with 99Mo of high specific activity obtained by thermal neutron fission of U-235. Concerted efforts have been put to develop user-friendly 99mTc delivery systems using 99Mo of low-medium specific activity obtained by neutron activation of natural MoO3 targets. The aim of this study is to develop a simple and automated 99mTc-generator for use of (n, γ)99Mo. Methods An alkaline solution of 500mCi 99Mo-molybdate (3g of carrier 98Mo in 5ml 5N NaOH) was immobilized onto a column (4cm x 2.8cm) of neutral alumina support (16g), which was then eluted with 15ml methyl ethyl ketone and the eluate was passed through another small column of acidic alumina (5g). The acidic alumina column was then washed with 10ml water and 99mTc was finally eluted with 5ml saline. All the operations were carried out in an aseptic and closed system. The quality control of pertechnetate and efficacy in labeling of kits of EC, L,L-ECD, MDP and MIBI were checked. Results The yield of separation was about 80-90% (n=20). All the 99mTc eluates were clear solutions with pH 5-6. The R.C. Purity of pertechnetate was >99%, while that of the labeled compounds was >95%. The content of MEK was less than 0.1% (v/v). The content of Al and Mo showed Conclusions Therefore a compact, user-friendly and inexpensive system of 99Mo-99mTc generator using (n,γ)99Mo has been developed for use in nuclear medicine hospitals.