RT Journal Article
SR Electronic
T1 Factors Affecting Reduction of Reference Endotoxin Standard Activity Caused by Chelating Agent/Detergent Matrices: Kinetic Analysis of Low Endotoxin Recovery
JF PDA Journal of Pharmaceutical Science and Technology
JO PDA J Pharm Sci Technol
FD Parenteral Drug Association (PDA)
SP pdajpst.2017.008086
DO 10.5731/pdajpst.2017.008086
A1 Tsuchiya, Masakazu
YR 2017
UL http://journal.pda.org/content/early/2017/09/18/pdajpst.2017.008086.abstract
AB Reduction of reference standard endotoxin (RSE) activity was kinetically analyzed under low endotoxin recovery (LER) conditions, and was considered as an apparent first-order reaction. Temperature, pH, and salt concentrations affected the rates of reduction of RSE activity. Temperature appeared to be the most important factor affecting LER. Components of LER matrices, such as citrate and polysorbate 20 showed similar LER effect at concentrations commonly used. Phosphate concentrations showed negative correlation against the half-life of RSE activity in solutions containing phosphate buffer and polysorbate 20. Activation energy for LER with naturally occurring endotoxin (NOE) was higher than that with RSE, and this explained one of the reasons for NOE resistance to LER. Lower temperature, lower pH, and a higher salt concentration are preferable to avoid LER in a hold-time study. This study provides useful data for anticipation of the severity of the LER effect and future hold-time studies in the biopharmaceutical field.