RADIOFREQUENCY MICROTOOLS FOR PARTICLE AND LIVE CELL MANIPULATION

Single particles can be manipulated by applying high frequencies to ul tramicro electrode arrays fabricated on planar structures. Heat produc tion can be reduced to the extent that intense electric fields can be applied even to unmodified cell culture media. Animal cells grow norma lly in the high field (up to 100 kV/m) between such continuously energ ized multielectrodes. As with laser tweezers [1-3], this technique can capture particles and cells in field traps, generate linear movement, and permit cell cultivation. It can also produce micropatterns of pH gradients, field-cast objects, and control cell adhesion. These microt ools may be combined to develop cell separators, microsensors, and con trolled-biocompatibility surfaces.