The complexation of Ni(H) with alpha-dioximes, which occurs due to the contact of Ni-2[Fe(CN)(6)] gelatin-immobilized matrix implants with water-alkaline (pH 12.0 +/- 0.1) solutions of dimethylglyoxime, alpha-benzyldioxime, and nioxime (H2L) used as ligands, was studied. It was shown that in each system, the [Ni(HL)(2)], [Ni(H2L)(2)](2+), and [Ni(H2L)](2+) coordination compounds were formed, while in the Ni(II)-dimethylglyoxime system at pH > 13, the [NiL(OH2)(2)] complex was additionally formed.