Liquid–liquid extraction in flow of the radioisotope titanium-45 for positron emission tomography applications. Issue 6 (12th October 2018)

• Record Type: Journal Article
• Authors: Pedersen, Kristina Søborg; Imbrogno, Joseph; Fonslet, Jesper; Lusardi, Marcella; Jensen, Klavs F.; Zhuravlev, Fedor
• Is Part Of: Reaction chemistry & engineering. Volume 3:Issue 6(2018)
• Page Start: 898
• Page End: 904
• Publication Date: 2018-10-12
• Subjects: Reaction mechanisms (Chemistry) -- Periodicals; Chemical engineering -- Periodicals; Chemical engineering; Reaction mechanisms (Chemistry); Periodicals; 547.705
• DOI: 10.1039/c8re00175h
• Languages: English
• ISSNs: 2058-9883

Abstract

Abstract : The continuous liquid–liquid extraction of the PET radioisotope 45 Ti using a membrane-based separator allows for efficient 45 Ti recovery and radiolabeling. Abstract : A continuous liquid–liquid extraction of nat Ti and its PET radioisotope 45 Ti into an organic phase from 12 M HCl is described. The extraction is completely selective with respect to Sc, which is commonly used as a cyclotron target for 45 Ti production. A membrane-based separator with integrated pressure control allowed for efficient, reproducible, and robust aqueous/organic phase separation in flow. Optimization studies established a guaiacol–anisole 9/1 (v/v) mixture and a flow rate ratio of 1/3 (aq. to org.), with a residence time of 13.7 s as the optimal extraction conditions. 90.3 ± 1.1% of nat Ti was consistently extracted from a 0.01 M solution of nat TiCl4 and ScCl3, while 84.8 ± 2.4% of 45 Ti was extracted from 0.03–0.13 M ScCl3 containing picomolar amounts of the 45 Ti radionuclide, without extracting any Sc from either system. The organic phase can be directly used for 45 Ti-radiolabelling as demonstrated by the efficient radiosynthesis of the 45 Ti-radiolabeled antineoplastic [ 45 Ti](salan)Ti(dipic). This development opens a pathway to achieve continuous and efficient 45 Ti recovery and processing using an automated micro or millifluidics setup.