Cadmium uptake by cultures of transformed hairy-roots of Solanum nigrum was studied. The effect of pH, buffer type, temperature, exposure time and Cd2+ content ranging from 0.2 to 2000 ppm was measured. Cd2+ uptake was dependent on increasing metal concentration and it was time dependent. From the variety of buffers tested, MES buffer and berate ions were found to be beneficial for the Cd2+ uptake. The high effectivness of Cd2+ accumulation in the roots decreased significantly after increasing the Cd2+ content in the buffer over 2 ppm.