Optimized separation procedure for production of no-carrier-added radiomanganese for positron emission tomography

The Cr-nat(p, xn)-process is a very efficient route for production of Mn-52g (T-1/2 = 5.59 d). Based on measurements of distribution coefficients with differentmedia and ion- exchange resins, an optimized chromatographic separation of radiomanganese from Cr-nat with the resin Amberlite CG400 was developed. With this system Cr-nat is eluted first with an acetic acid/methanol 1 : 1 mixture at room temperature and Mn-52g thereafter with 3M HCl at 50 degrees C. Within a separation time of 4 h the method yielded 99.5% of the n.c.a. Mn-52g in 2-3mL of 3M HCl. An ICP-MS analysis revealed a chromium impurity of 0.07mg (0.014%) in the n.c.a. Mn-52g solution, making this separation method suitable for the production of Mn-52g formedical applications like positron emission tomography (PET).