• Swiss testing laboratory

USP 85

Bacterial Endotoxin Test (BET)
Get In Touch

Hassle-free testing experience

Need to get a product tested? No worries! To and fro logistics are on us; we collect your products, test them and, deliver them back to you.

Related tests for you

Sterility testing of Pharmaceutical Products
Antimicrobial Effectiveness Test
Ensuring Safety in Non-Sterile Medical Products

Quick understanding of the test

Introduction to USP 85 - Bacterial Endotoxin Test (BET)

Purpose

USP 85 (Bacterial Endotoxin Test) is an in vitro assay to detect endotoxins contamination in drug products and medical devices.

Application

Applicable to a wide range of products, including parenteral drugs, biological products, vaccines, and more.

Methodology

Endotoxin detection is performed using Limulus Amebocyte Lysate (LAL), employing one of three techniques:

  • Gel-Clot technique
  • Turbidimetric technique
  • Chromogenic technique

Benefits

  • Bacterial Endotoxin Test is part of the quality control process for manufacturing pharmaceuticals and medical devices.
  • The test provides essential data that aid in risk management and processes concerning product safety and batch release.

Turnaround Time

It typically takes 3-4 weeks .

Results

Results are evaluated by comparing endotoxin levels in the sample to the specified limit.

Passing criteria

The passing criterion for USP 85 is that the endotoxin levels in the product must be below the specified regulatory limit for its intended use.

Do you have a product that needs testing?

Get a quote from our experts today!
Get a quote

Abstract

USP 85 Bacterial Endotoxins Test (BET) which is commonly known as the LAL (Limulus Amebocyte Lysate) test, is an important assay for detecting endotoxins to ensure the safety of pharma products and medical equipment.

Endotoxins are part of the outer membrane of the cell wall of Gram-negative bacteria. They are released when bacteria disintegrate or during bacterial growth. Sterilization processes that usually kill bacteria might not be effective enough to deactivate endotoxins. Therefore, products must be effectively tested to ensure that they are free from any remnants of endotoxins, which might pose a risk.

Guidelines for Conducting USP 85 Bacterial Endotoxin Testing

  • The sensitivity of the lysate needs to be confirmed with every batch used. The labeled sensitivity, ฮป, has to be within the valid range (0.5ฮป – 2ฮป) usually verified by conducting tests using standard endotoxin solutions.
  • A preparatory test is required to ensure that the sample does not contain any substances that will interfere with the detection of endotoxin. 
  • The test should be carried out at the incubation temperatures specified by the manufacturer. In the case of the gel clot method, incubation is usually done at 37 ยฑ 1ยฐC for 60 ยฑ 2 minutes.
  • The test’s lysate sensitivity and accuracy must be verified using standard endotoxin solutions as positive controls.
  • If interference is detected, then it should be eliminated from the sample using methods such as dilution, filtration, neutralization, or heating.

Test methodology

Endotoxin testing methods entail the use of Limulus Amebocyte Lysate (LAL), which is extracted from the blood cells of the horseshoe crab, Limulus polyphemus. This lysate is endotoxin-sensitive and forms the basis of the test techniques detailed below.

Qualitative technique: Gel-clot technique

This technique is based on the clotting of the lysate reagent in the presence of endotoxins. In this assay, a clot forms in the bottom of the test tube in the presence of endotoxins above a specified threshold. The minimum endotoxin level required to form the clot is termed as the labeled sensitivity of the lysate. This test is qualitative, meaning it only confirms the presence of endotoxins but does not provide its concentration.

Quantitative techniques: Photometric techniques

Photometric methods are quantitative and include two main types:

1. Turbidimetric: This technique measures the increases in turbidity of the reaction mixture caused by endotoxins. There are two types:

  • Endpoint-turbidimetric assay: The endpoint of the reaction is measured; a quantitative result is obtained.
  • Kinetic-turbidimetric assay: The rate or time at which a certain level of turbidity is obtained is measured.

2. Chromogenic: The Chromogenic technique measures the color change that occurs when endotoxins react with a reagent added to LAL. It may also be carried out in two variants:

  • Endpoint-chromogenic assay: The color produced is measured at the end of incubation.
  • Kinetic-chromogenic assay:  The rate of color development is monitored.

Applications and Importance of USP 85 Endotoxin Testing

Bacterial endotoxin testing is an essential component in monitoring the quality as well as safety of manufactured products such as pharmaceuticals and medical devices. Here’s a detailed look at the various applications and why this testing is indispensable.

Photometric techniques

In the case of injectable drugs, whether vaccines or biologics, endotoxins can cause severe immunologic reactions. The BET test ensures that these products are not contaminated with endotoxins that cause side effects such as fever, inflammation or even septic shock in individuals.

Medical devices

Medical devices that have direct or indirect contact with the cardiovascular system, central nervous system, or those devices that are implantable must undergo very strict endotoxin testing. This entails products like catheters, stents, and implants. BET makes certain that these devices will not trigger an immune response that will result in the development of complications or device rejection.

Intravenous solutions

The fluids to be administered intravenously have to be endotoxin-free to prevent pyrogenic reactions in patients.

Surgical and procedural kits

Products used in performing medical procedures or surgeries may have parts which come into contact with body tissues. These materials must be carefully checked for endotoxins since postoperative infections and complications due to endotoxins are extremely dangerous.

Ophthalmic products

Products used in ophthalmology such as eye drops and contact lens solutions, require the endotoxin level to be very low since the eye is sensitive and prone to infection. Endotoxin testing of these products is useful in reducing incidences of eye injuries including irritation and other severe eye complications.

Transdermal patches

Transdermal drug delivery systems deliver medication through the skin. As these patches are an entryway to blood, it becomes necessary to screen for endotoxins in order to prevent skin reactions and systemic toxicity.

Dialysis equipment

In the case of patients on dialysis, it is important that all equipment employed is endotoxin free particularly the dialysate and other fluids. Endotoxins may cause adverse effects including fever and hypotension and these are potentially fatal in renal patients.

Biotechnology products

Biotechnological products, especially those produced using bacterial cultures, may be prone to endotoxin contamination. Endotoxin testing is vital to ensure that these products, which include enzymes and recombinant proteins, are safe for human use.

Advantages of Endotoxin Testing

Endotoxin testing offers several advantages:
  • Sensitivity
    The test detects the lowest levels of endotoxins, which is important for product safety.
  • Versatility
    The test can be applied to a diverse range of product types, including liquid, solid, and devices.
  • Acceptance by regulatory bodies
    Results obtained by performing this test are generally accepted by most regulatory bodies worldwide. Hence, the product is acceptable in international markets.

Frequency and Timing of USP 85 Test Method

The frequency of testing for bacterial endotoxin varies from product to product and its intended application. In general, testing must be performed:
  • In the development phase to ensure that raw materials and intermediates must be free from endotoxin contamination.
  • As a final quality control check to ensure that the finished product conforms to regulatory limits for endotoxins.
  • Periodic testing for the presence of endotoxins in products under ongoing production to ensure that contamination does not occur during production processes.

How can MIS help you with Endotoxin Testing services?

At Microbe Investigations Switzerland, we specialize in providing accurate USP 85 testing services to ensure the safety and quality of your pharmaceutical products. Trust our expertise for reliable results that meet stringent regulatory standards.

Contact us today to learn more about how we can support your product testing needs!

Frequently Asked Questions

DR. Martinoz Scholtz

MIS Labs
1. What is the Limulus Amebocyte Lysate (LAL) test in USP 85?
The LAL test detects the presence of bacterial endotoxins by using the blood cells of the horseshoe crab, which clots in the presence of endotoxins.
2. What industries are required to comply with USP 85?
Manufacturers of pharmaceuticals, biologics, and medical devices comply with this standard.
3. How are samples prepared for endotoxin testing?
Samples are prepared by dissolving or suspending the test article in an appropriate solvent to ensure that the solution is endotoxin-free.
4. What is the Chromogenic method in USP 85?
The Chromogenic method uses a color change to detect and quantify endotoxins, providing highly sensitive and quantitative results.
5. How is USP 85 different from USP 71 sterility testing?
While USP 85 tests for endotoxins, USP 71 tests the sterility of the products.
6. Is USP 85 harmonized with EP?
Yes, this standard is harmonized with the European Pharmacopeia (EP) to ensure consistency across global regulatory frameworks.

Meet the best of the blend of
R&D, Efficacy Testing,
Innovation and Passionate
Experts at MIS.

Send us your sample and experience High quality Swiss standards, Industry leading turnaround times, and affordable prices.
Ask us about our Fast Track program!

    Image1.png
    Image2.png
    Image3.png
    Image4.png
    Image5.png

    Explore More

    challenge testing for cosmetics

    What is Challenge Testing for Cosmetics?

    In the cosmetics industry, safety

    Cosmetic Product Safety Testing Methods

    Cosmetic Product Safety Testing Methods

    Evidently, with the expanding cosmetics

    Efficacy Testing: The Method for Validating the Claims of Skincare Products

    Efficacy Testing: The Method for Validating the Claims of Skincare Products

    In the competitive world of

    Microbe Investigations Switzerland

    Get your products tested today

    Explore now
    We also partner with over 16 labs (both GLP and non-GLP) for extended support.