The Passive Lysis Solution (PLS) is a mammalian cell lysis solution intended to be used to prepare cell lysates for measurement of luciferase activity with the twinlite and sensilite reporter gene assay systems. It is provided in the twinlite and Sensilite kits, but if additional volume of the lysis solution is required, it is also available as a separate item, 100 mL volume per bottle.