Reproducible layering of tissue culture cells onto electrostatically charged membranes

This procedure provides a reproducible method to collect cells on 10-mm-diameter Zeta-Probe blotting membrane discs. This method allows for a defined number of cells to be available for studies with intact tissue in cell-tissue electrofusion protocols. In addition, this procedure can be used to rapidly and efficiently remove nonadherent cells from suspension cultures. The number of cells placed on these electrostatically charged membranes can be quantitated spectrofluorometrically or by microscopic count. Once the cells are placed on the Zeta-Probe they can be moved or inverted without falling off. In addition, the discs can remain at room temperature for 3 to 5 h without a significant change in the number of layered cells or an adverse effect on the fusion process. The ability to control the number of cells placed in contact with tissue will allow for the further development of cell-tissue electrofusion.