Abstract
The thermal inactivation of three endotoxin preparations on the inner surface of glass capillary tubes was studied. The samples were exposed to precisely controlled dry heat conditions at study temperatures ranging from 170° to 350°C, and were assayed using the gel-clot method of the Limulus Amebocyte Lysate test. Plots of the log of the amount ofpyrogenic material remaining versus heating time revealed apparently biphasic destruction curves. The initial slopes were linear to a minimum 3-log unit reduction, and were followed by slower destruction rates for the terminal slopes. D values were calculated from the initial slopes of the destruction data, and Z values were estimated from the D values. The D and Z values were found to vary with the initial charged amounts of endotoxin. A second-order equation was found to be an inappropriate model for the inactivation process at temperatures between 170° and 250°C, but was found to be suitable for temperatures between 250° and 325°C. The data were successfully fit to a biexponential equation for all the temperatures studied. The overall inactivation rate of the endotoxin material formulated with fillers was apparently faster than that for the pure endotoxin preparations.
- Received December 28, 1988.
- Accepted June 22, 1989.
- Copyright © Parenteral Drug Association. All rights reserved.
PDA members receive access to all articles published in the current year and previous volume year. Institutional subscribers received access to all content. Log in below to receive access to this article if you are either of these.
If you are neither or you are a PDA member trying to access an article outside of your membership license, then you must purchase access to this article (below). If you do not have a username or password for JPST, you will be required to create an account prior to purchasing.
Full issue PDFs are for PDA members only.
Note to pda.org users
The PDA and PDA bookstore websites (www.pda.org and www.pda.org/bookstore) are separate websites from the PDA JPST website. When you first join PDA, your initial UserID and Password are sent to HighWirePress to create your PDA JPST account. Subsequent UserrID and Password changes required at the PDA websites will not pass on to PDA JPST and vice versa. If you forget your PDA JPST UserID and/or Password, you can request help to retrieve UserID and reset Password below.