Dielectrophoresis and electrorotation of Neurospora slime and murine myeloma cells

摘要: Dielectrophoresis and electrorotation are commonly used to measure dielectric properties membrane electrical parameters of biological cells. We have derived quantitative relationships for several critical points, defined in Fig. A 1, which characterize the dielectrophoretic spectrum electrorotational a cell, based on single-shell model (Pauly, H., H.P. Schwan, 1959. Z. Naturforsch. 14b:125–131; Sauer, F.A. 1985. Interactions between Electromagnetic Field Cells. A. Chiabrera, C. Nicolini, editors. Plenum Publishing Corp., New York. 181–202). To test these equations obtain parameters, technique allowed simultaneous measurements dielectrophoresis single cells same chamber, was developed applied study Neurospora slime Myeloma Tib9 cell line. Membrane were determined by dependence first frequency (fct1) characteristic (fc1) conductivity suspending medium. conductances also found be 500 380 S m-2, respectively. Several observations indicate that more complex than described model. First, capacities from fct1 (0.81 x 10(-2) 1.55 F m-2 neurospora Myeloma, respectively) at least twice those fc1. Second, deviated like behavior. These discrepancies could eliminated adapting three-shell (Furhr, G., J. Gimsa, R. Glaser. Stud. Biophys. 108:149–164). Apparently, there one relaxation process influence lower region beta-dispersion. medium given external similar most cells, but some dramatically increased recorded. Model analysis suggested decrease cytoplasmatic due drastic ion loss cause this increase fct1. counter-field rotation range fc1 would sensitive changes cytoplasmic fluid internal membranes fct1, although latter capacitance membranes.