Endotoxin contamination of protein solutions was reduced by a phase separation technique
using the detergent, Triton X-114. Protein solutions containing endotoxin were treated with
Triton X-114 on ice. The solution was then warmed to 37° C, whereupon two phases formed.
The Triton X-114 phase, containing the endotoxin, was precipitated by centrifugation. The
first cycle of phase separation produced a 1000-fold reduction of endotoxin from
contaminated preparations of cytochrome c, catalase and albumin. Complete removal of …