A method and apparatus for isolating and purifying a 213Bi radioactive isotope from an 225Ac source using a primary column and a primary sorbent which preferentially retains 225Ac over 213Bi when exposed to a compatible solvent in combination with a secondary column having a secondary sorbent which retains 213Bi when exposed to a mixture of the compatible solvent and 213Bi. Said fixture comprises a clamping piece support which can be moved in a guided manner on the profiled support in the longitudinal direction of the profiled support and can be braced with the profiled support so as to enclose a frame section of the solar module and a clamping piece that is guided within the clamping piece support. In one example, the coil inductor can be formed by first conductive lines extending along the first surface of the microelectronic or interconnection element, second conductive lines extending along the second surface of the microelectronic or interconnection element, and a plurality of conductive vias, e.