USP <85>

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 is applicable to test medical devices, intravenous solutions, opthalmic products, injectable medications and other biological products.

It takes 3-4 weeks to complete the USP 85 test.

Endotoxin testing is a laboratory method employed in the identification and quantification of endotoxins that are derived from the cell walls of gram-negative bacteria, specifically lipopolysaccharides. The main objective of endotoxin testing is to ensure that the product does not contain any toxic levels of endotoxin that will harm the patient.

The Bacterial Endotoxin Test (BET) or Limulus Amebocyte Lysate (LAL) test is a routine assay that measures the endotoxins. The test employs the principle that the blood of horseshoe crabs coagulates when endotoxins are present. There are three main types of LAL tests: gel-clot, turbidimetric and chromogenic methods.

Endotoxin testing plays a vital role in eliminating the risks of use of contaminated pharmaceuticals, medical devices, and biologics. Endotoxins can act as pyrogens, which are agents that can induce fever, shock, and even death if administered into the human body through injectable medications, intravenous solutions or implantable medical devices. Testing helps manufacturers to effectively eliminate contaminated products from the market.

Endotoxin refers to a toxic substance that is present in the outer membrane of gram-negative bacteria. From the chemical point of view, endotoxins are lipopolysaccharides (LPS) containing lipid A moiety that produces a toxic effect and a polysaccharide chain. Endotoxins are known to incite strong responses from the body’s immune system when they circulate in the bloodstream or infiltrate tissues and can cause fever, inflammation, septic shock, and sometimes death.

Endotoxin testing becomes mandatory during manufacturing and quality control of products, which come in contact with blood circulation or are intravenously administered, be it a pharmaceutical product, a medical device, or a biologic product, etc. Products like dialysis solutions, surgical implants, as well as other sterile medical products, must also guarantee that their endotoxin levels do not go over a particular threshold.

One of the most common methods employed in the quantification of endotoxins in a particular sample is through the use of the turbidimetric method. In this test, the endotoxins cause a reaction, which leads to turbidity or cloudiness of the solution. The level of turbidity increases with the concentration of endotoxin and is determined through spectrophotometer value.

Endotoxin contamination is never acceptable in injectable medications due to possible severe adverse effects in patients. Endotoxins are capable of eliciting fever, chills, septic shock, as well as other fatal consequences if injected into the bloodstream. Quality control acceptance and regulatory compliance can only be accomplished when injectable medications are free from endotoxin.