RT Journal Article SR Electronic T1 F Value Requirements for the Destruction of Endotoxin in the Validation of Dry Heat Sterilization/Depyrogenation Cycles JF PDA Journal of Pharmaceutical Science and Technology JO PDA J Pharm Sci Technol FD Parenteral Drug Association (PDA) SP 23 OP 27 VO 36 IS 1 A1 Michael J. Akers A1 Kathryn M. Ketron A1 Barbara R. Thompson YR 1982 UL http://journal.pda.org/content/36/1/23.abstract AB Ten nanograms of E. coli endotoxin (10 ng. of type 055:B5) was placed in sterile, pyrogen-free 50-ml vials and exposed to dry heat oven temperatures of 175, 210, and 250 °C. Exposure time at these temperatures was based upon equivalent time (F value) using a Z value of 54 °C and a reference temperature value of 170 °C. The Limulus Amebocyte Lysate (LAL) test was used to test for the presence of endotoxin in the vials following heat exposure, and the LAL test results were correlated with the corresponding F values achieved. A linear relationship was found between oven temperature and the logarithm of the F value. Minimum F value requirements were proposed for destruction of E. coli endotoxin (type 055:B5) at different temperatures. Destruction kinetics of endotoxin is suggested to be second order. Destruction of endotoxin appears to occur more rapidly by radiant heat than by convection heat at 250 °C.