[en] Under the coordinated research project (CRP), concerted efforts were made to develop ⁹⁰Sr/⁹⁰Y generator systems to obtain ⁹⁰Y in high yields and of high purity. A two stage ⁹⁰Sr/⁹⁰Y generator based on the supported liquid membrane (SLM) concept was developed in order to obtain ⁹⁰Y in acetate form as well as to minimize ⁹⁰Sr contamination of the ⁹⁰Y product to well below acceptable limits. In 10 h of operation, the generator yielded approximately 85% of highly pure ⁹⁰Y for therapeutic purposes. During the period of the CRP, approximately 1.85 GBq (500 mCi) of ⁹⁰Sr was recovered from high level liquid waste using multistep processes involving, for example, precipitation and ion exchange. A 740 MBq (20 mCi) capacity ⁹⁰Sr/⁹⁰Y generator based on a novel electrochemical procedure was also developed. Since the parent ⁹⁰Sr is a highly radiotoxic isotope, efforts were made to develop quality control procedures to detect ⁹⁰Sr contamination in the ⁹⁰Y eluted from the generator. A novel extraction paper chromatography technique was developed based on the high affinity of the reagent 2-ethylhexyl 2-ethylhexyl phosphonic acid (KSM-17) for ⁹⁰Y. This technique is capable of detecting levels of ⁹⁰Sr as low as 74 kBq (2 μCi) of ⁹⁰Sr in 37 GBq (1 Ci) of ⁹⁰Y. Quality control of the ⁹⁰Y eluted from the SLM based and electrochemical generators showed the ⁹⁰Sr levels to be much less than the allowed limits. (author)