A possible route for the production of no-carrier-added (n.c.a.) Se-73 (T-1/2 = 7.1 h) and Se-75 (120 d) is introduced.D,L-2-Amino-4-([Se-73]methyl-seleno) butanoic acid (D,L-[Se-73]selenomethionine) with an overall radiochemical yield of > 40% could be prepared via a 3-step polymer-supported synthesis after successful separation of Se-73 from KBr targets. Excitation functions for the Br-nat(p,x) Se-72,Se-73,Se-75 processes were measured from threshold up to 100 MeV utilizing pellets of pressed KBr. Targets were irradiated at the NAC cyclotron with proton beams having primary energies of 40.4, 66.8 and 100.9 MeV. The calculated 73Se yield (EOB) for 1 h irradiation in 1 muA of beam at the optimum proton energy range of 62 --> 42 MeV is 81.4 MBq (2.2 mCi), and the calculated Se-75 yield (EOB) for the overall range 62 MeV --> threshold for the same irradiation conditions is 0.97 MBq (0.026mCi). (C) 2001 Elsevier Science Ltd. All rights reserved.