Microscopic Visualization of Insect Cell-Bubble Interactions. I: Rising Bubbles, Air-Medium Interface, and the Foam Layer

Through the use of microscopic, high‐speed video technology, the interactions of two suspended insect cell lines, Trichoplusia ni (TN‐368) and Spodoptera frugiperda (SF‐9), with air and oxygen bubbles were studied. Events such as cell‐bubble attachment, cell‐bubble collision, cell transport into the foam layer, and trapping of cells in the foam layer are presented and discussed. Based on these observations and those in a companion paper (Chalmers, J. J.; Bavarian, F. Biotechnol. Prog. 1991, following paper in this issue) and the experimental and theoretical work of other researchers, several mechanisms of cell damage as a result of sparging are presented.