Cell culture perfusion chamber: adaptation for microscopy of clonal growth.

Silicone rubber O-rings used as gaskets in Sykes-Moore cell culture perfusion chambers are permeable to carbon dioxide. When small numbers of cells are planted in such chambers, loss of carbon dioxide leads to an undesirable increase in pH and inhibits cell multiplication. Substitution of Teflon O-rings prevents this loss and allows a constant carbon dioxide tension to be maintained within the chamber. The rate of growth and plating efficiency of small numbers of cells planted in the modified chambers have been found to be comparable to those observed in conventional culture vessels. The necessary additional parts of the chamber are described, and the modifications in procedure outlined.