Endotoxin unit

Pyrogenic A fever-producing substance. The presence of these substances is determined by the Limulus Amebocyte Lysate (LAL) test and measured in EU/ml (endotoxin units per milliliter). 

Pyrogens the endotoxins responsible forfebrile reaction on injection, determined either by the rabbit test or the LAL test. Units are Endotoxin unit/ml (EU/ml). 

Bacterial endotoxins. When tested according to the general test <85>, miconazole injection contains not more than 0.1 USP Endotoxin Unit per mg of miconazole. 

Where the test is conducted as a limit test, the specimen is determined to be positive or negative to the test judged against the endotoxin concentration specified in the individual monograph. Where the test is conducted as an assay of the concentration of endotoxin, with calculation of confidence limits of the result obtained, the specimen is judged to comply with the requirements if the result does not exceed (1) the concentration limit specified in the individual monograph and (2) the specified confidence limits for the assay. In either case the determination of the reaction endpoint is made with parallel dilutions of redefined endotoxin units. 

With respect to endotoxin content, the FDA requires that each dose have less than 0.5 endotoxin units (EU) for each ml of... 

To fulhll the monograph requirements with respect to the maximum allowed pyrogen content of about 0.25 endotoxin units per ml, the water used for distillation must be of very high microbial quality. 

Prepare five stoppers covered with 1000 endotoxin units each. Place the stoppers in a net and place them in the process vessel during a standard run with a 100% loading. Determine the endotoxin quantity present on the five stoppers. 

Determine endotoxin potency (EU/ng) from certificate of analysis (C of A). Calculate endotoxin units per milliliter (EU/ml), based on C of A. 

Endotoxin unit/ml = dilution factor of last end point (D.F.) x LAL reagent sensitivity... 

PW, purified water WFI, water for injection EU, endotoxin units Pyrogen, pyrogen test (qualitative). 

The endotoxin limits (measured by endotoxin units, or EU) apply for drugs and devices administered to humans or animals are listed below ... 

The purification process was scaled up 10-fold from 100 to 1000 cm2 of stacked 142 mm disks. The scale-up exhibited a good separation with a 7 log reduction in endotoxin levels. The yield was 98% with a final purity of 98.2%. This process was again scaled up with the modular configuration described previously (Fig. 3). Two 30-layer 4 m2 Q modules were used in conjunction with a 1 m2 C module. The chromatograms appeared very similar to the 1000 cm2 purification. The product purity was found to be 99.7% with < 0.002 endotoxin units per microgram of product and 0.003 pg DNA per microgram of product. The final product exceeded the clinical pharmaceutical specifications for this product. 

Note that WFI is essentially the same as purified water with the exception of endotoxins and bacteriological purity. USP requires WFI to contain less than 0.25 USP Endotoxin Unit per ml. The USP has no bacteriological purity requirements for WFI at all. However, the proposed large volume parental GMP s (CFR 212.49) requires counts less than 10 CFU/100 ml. 

The crude viral harvest was tested for adventitious agents as needed to comply with current regulatory guidelines. Purified virus was tested to confirm the absence of RCAs, residual host ceU proteins and DNA, endotoxin, and to quantify total and infectious vector particles and thus, the in-fectivity ratio. Bulk virus lots were released after meeting specifications which included one or more endotoxin unit mL and infectivity ratios of > 2% (infectious ti-ter/total viral particles). 

Removal of endotoxin from manufacturing equipment or materials can be done by appropriate washing and rinsing procedures. Pyrogen-free water can be obtained by several means. The oldest and most effective method is distillation —the heavyweight lipopolysaccharide molecules (MW of around 10 ) are left behind when water is rapidly boiled in a still. Reverse osmosis can remove 99.5 to 99.9% of water s endotoxin load in a single pass. For these reasons, distillation and reverse osmosis are the only two methods of preparing Water for injection allowed in the pharmacopoeias. The pharmacopoeial requirement for Wtuer for injection is that there should be no more than 0.25 EU (endotoxin units)/mL. 

The LAL assay is at present the most widely accepted assay for endotoxin measurements, having been adopted as the standard assay for endotoxin detection by the United States Food and Dmg Administration (FDA) in 1980. The more recent kinetic chromogenic versions of the LAL assay are very sensitive and have a broad measurement range (0.01 -100 Endotoxin Units (EU)/ml w 1 pg/ml-10 ng/ml). The detection limit for airborne endotoxin measurements is approximately 0.05 EU/m (5 pg/m ). Since different test batches may give different results an internal standard must be used. The U.S. FDA... 

The bacterial endotoxin limit for WFI does not exceed 0.25 USP endotoxin units per ml. The microbial action limit is not greater than 10CFU/100 ml. 

Abbreviations BKA, bicinchoninic acid LAL, Lymulus amebocyte lysate EU, endotoxin units. 

The use of oxidizing agents such as hydrogen peroxide or henzoyl peroxide has also reduced the endotoxin content to less than 20 endotoxin units/gram of PHA, and this PHA did not result in an acute inflammatory response when implanted in animal models. ... 

In humans, contact with LPS may occur not only during a bacterial infection but also via LPS-contaminated medicaments and solutions administrated intravenously (parenteralia). Since the biological effects of LPS may appear even at concentrations of 1 ng per 1 kg of body weight, drugs intended for parenteral use, have to be endotoxin-free , i.e., thoroughly depyrogenated. In fact parenteralia have to comply with LPS threshold limits (in EU , endotoxin unit) regulated by pharmacopoeias. For example, tetracycline hydrochloride may not contain more than 0.5 ELf/mg. Similar limits exist for insulin (0.8 EU/insulin unit), hyaluronidase (2.3 EU/ hyaluronidase unit), the sodium salt ofheparin for injection (0.003 EU/heparin unit). ... 

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