Quantification of cellular properties from external fields and resulting induced velocity: Magnetic susceptibility

An experimental technique is discussed in which the magnetic susceptibility of immunomagnetically labeled cells can be determined on a cell-by-cell ba sis. This technique is based on determining the magnetically induced veloci ty that an immunomagnetically labeled cell has in a well-defined magnetic e nergy gradient. This velocity is determined through the use of video record ings of microscopic images of cells moving in the magnetic energy gradient. These video images are then computer digitized and processed using a compu ter algorithm, cell tracking velocimetry, which allows larger numbers (>10( 3)) of cells to be analyzed. (C) 1999 John Wiley & Sons, Inc.