I am studying the effects of an modified adenovirus on different cancer cells. The problem is that most cytotoxicity assays rely on the use of a spectrophotometer for measuring absorbance etc. This cannot be done in our department with virus transduced cells because these cells cannot be transferred from the virus lab. The lab itself contains no measuring possibilities. In other words, the cells (and virus inside) must be fixed/neutralized before any kind of measurements. In addition to using trypan blue, any suggestions how to measure virus cytotoxicity or cell viability?