INTRODUCTION Elaboration of new, inexpensive, and efficient methods of purifying natural and waste waters has re- cently become a relevant problem due to heavy metal pollution of the environment. Biosorption is a prom- ising method of waste water purification from heavy metal ions. In designing biosorbents, particular atten- tion is focused on yeast biomass, a promising sorbent of heavy metals [1]. Yeast grow fast, their cells are easy to manipulate at the genetic and morphological levels, they are able to grow at high concentrations of heavy metals, and accumulate them in their biomass. Yeast biomass can easily be obtained as a byproduct of numerous fermentation processes [1, 2]. Furthermore, the cost of biosorbents is ten times lower than the cost of commercial ion-selective res- ins, which makes them a competitive sorption mate- rial [3]. In spite of achievements in application of biosorbents, postprocessing methods of extraction of biomass with accumulated ions of heavy metals re- quire further development. Biosorbents with magnetic labels, which combine biosorption with high-gradient magnetic separation, are currently being actively stud- ied [4]. In the last decade there has been growing interest in the processes that occur in electrolyte solutions in magnetic field. Ample reliable experimental data, which have been successfully used for practical appli- cations, have accumulated in this field. One of the most thoroughly studied effects in this field is mass transfer in crossed electric and magnetic fields [5–8]. It is well known that stirring of electrolytes usually leads to acceleration or modification of chemical and electrochemical processes in them [9–13]. Thus, the phenomenon of magnetohydrodynamic stirring of elec- trolytes in crossed electric and magnetic fields was the basis for developing more sophisticated methods of magnetoelectrochemical co-deposition of several met- als and inert particles, obtaining higher quality coating during cathode metal deposition, and ensuring chaotic magnetohydrodynamic stirring of electrolytes (similar 452 ISSN 0006-3509, Biophysics, 2006, Vol. 51, No. 3, pp. 452–456. © Pleiades Publishing, Inc., 2006. Original Russian Text © S.V. Gorobets, O.Yu. Gorobets, I.Yu. Goiko, T.P. Kasatkina, 2006, published in Biofizika, 2006, Vol. 51, No. 3, pp. 504–508. CELL BIOPHYSICS Intensification of Biosorption of Copper Ions from Solution by the Yeast Saccharomyces cerevisiae in Magnetic Field S. V. Gorobets a , O. Yu. Gorobets b , I. Yu. Goiko a , and T. P. Kasatkina c a National University of Food Technologies, ul. Vladimirskaya 68, Kiev, 01033 Ukraine b Institute of Magnetism, National Academy of Sciences of Ukraine, ul. Vernadskogo 36-b, Kiev, 03142 Ukraine c Institute of Microbiology and Virology, National Academy of Sciences of Ukraine, ul. Zabolotnogo 154, Kiev, 03627 Ukraine Received April 9, 2004; in final form, January 13, 2005 Abstract—We studied the possibility of intensification of biosorption of copper ions by the yeast Saccharomyces cerevisiae 1968 from a copper sulfate solution by immersing a metal 80-rod headpiece into the solution and applying an external magnetic field. The field was parallel or perpendicular to the axes of headpiece rods. It was shown that intensification of extraction of copper ions at various geometries of the system differed insignificantly and that copper ions were extracted from the solution via biosorption and ce- mentation at the metal headpiece. DOI: 10.1134/S0006350906030183 Key words: copper ions, yeast, biosorption, effect of magnetic field Abbreviations: MF, magnetic field.