Global Footprint
LIMS system

USP 85

Bacterial Endotoxins Testing

Home >> USP 85

USP 85 – Bacterial Endotoxin Test (BET)

USP 85 (Bacterial Endotoxin Test) is an in vitro assay to detect endotoxins contamination in drug products and medical devices. This test can be conducted using 3 techniques, all of them are based on the Limulus amebocyte lysate (LAL).

The BET is performed as part of lot release testing for injectable pharmaceutical products and medical devices. The test aims to ensure given products are free of endotoxins and safe for patient use.

USP 85 Test Method

The bacterial endotoxin test (BET) is also known as LAL test. In the USP 85 test, product samples are screened for endotoxins by using Limulus Amebocyte Lysate (LAL). LAL is an aqueous extract of blood cells (amebocytes) from the Atlantic horseshoe crab, Limulus polyphemus.

LAL test can be performed based on following techniques –

  • The gel-clot technique: In gel-clot testing or gel-clot assay, the Limulus Amoebocyte Lysate (LAL) exhibits a clotting response upon exposure to endotoxins.
  • Photometric Quantitative Techniques:
    1. Turbidimetric endotoxin testing – Elevated levels of turbidity in LAL serves as an indicator of endotoxin presence.
    2. Chromogenic endotoxin testing – In presence of endotoxins, LAL undergoes a reaction wherein a chromophore is released from a chromogenic peptide.

For more information read our page on Gel-Clot Technique & Photometric Quantitative Technique.

Importance of USP 85 Test

Medical devices and drug materials may be sterile, however, they have been found to be contaminated by endotoxins. Endotoxins are lipopolysaccharides found in the cell wall of gram-negative bacteria, but when entered into the bloodstream of patients can cause fever and a wide range of other possible effects including septic shock and even death.

Inadequate manufacturing and storage practices serve as potential sources of endotoxin contamination in such products. The USP 85 test method effectively determines the presence or absence of endotoxins in drug products or medical devices.

At MIS, we specialize in offering Endotoxin testing services tailored to the needs of pharmaceutical and medical industries. With extensive expertise in research and developing microbiology analytical solutions, we provide the most adapted panel of test methods to investigate microbial contamination and antimicrobial resistance in newly developed formulations.

In our current testing capabilities, we also offer other USP tests like USP 61, USP 62, and USP 1111.

Our state-of-the-art laboratories are equipped with advanced technology to ensure accurate and reproducible results within the designated time frame.

Need further assistance with USP 85 testing services, contact our experts here.


USP 85 provides methods for the detection and quantification of endotoxin contamination in pharmaceutical products, medical devices, and similar materials. In USP 85, product samples are screened for endotoxins by using Limulus Amebocyte Lysate (LAL) test. LAL test can be performed using three techniques: Gel-clot, Turbidimetric, and Chromogenic Standard Endotoxin Stock Solution.

USP 85 test can be carried out for biologics, medical devices, injectable medications, ophthalmic products and intravenous solutions etc.

USP 85 test 3-4 weeks to complete.

Contact us for more information

    Explore Other Tests

    Leaving Already?

    Did not find the information you were looking for or need something specific!

      Sign up with Us! Enter your email address for a 10% discount!