The removal of bacterial endotoxins from biological samples is critical to avoid the potentially fatal pyrogenic response possible when introduced to mammalian systems. Endotoxins have a variety of specific characteristics that can be exploited to target their isolation and subsequent removal, but one that has not been extensively characterized is their difference in size from that of monoclonal antibodies. Here, we present a study which utilizes gel filtration chromatography as a method for endotoxin removal from both aggregated and nonaggregated antibody preparations, outlining a mechanistically simple method for removal of this impurity. (c) 2014 American Institute of Chemical Engineers Biotechnol. Prog., 30:1497-1501, 2014