Endotoxin Removal

What is Endotoxin?

Endotoxin or lipopolysaccharides (LPS) are highly toxic components of the outer cell membrane of Gram-negative bacteria. The general structure of all endotoxins is a polar polysaccharide chain, with three defined domains: The O-antigen region, a core oligosaccharide region and a Lipid A region.

What is the function of Endotoxin?

Endotoxins are often present in significant amounts in bacterial cell expression systems such as E. coli, which are widely used in the biotechnology industry for recombinant protein bio-therapeutics where endotoxin contamination can occur at any point within the processes. Endotoxin contamination in protein bio-therapeutic production processes generally occur when it is released from within the process or introduced by non-sterile process conditions.

The removal of endotoxin is extremely important prior to administration into human and animal tissues/ bodies to avoid any adverse side effects, such as causing fever and shivering, hypotension, adult respiratory distress syndrome, disseminated intravascular coagulation and toxic shock. Endotoxins are surprising difficult to remove as they interact with biomolecule containing positively charged and/ hydrophobic regions. Several downstream methods have been used including ‘historic’ affinity ligands such as polymixin B and L-histidine as well as anion exchange chromatography and membranes. These methods can work effectively but have distinct limitations including toxicity, cost and non-selectivity.


Etoxiclear™ is a high performance, non-ion-exchange, synthetic affinity chromatography adsorbent allowing cost effective and efficient endotoxin removal. Available as an adsorbent slurry for column packing and in an extensive range of disposable columns to suit your process. Etoxiclear™ adsorbent comprises a novel synthetic chemical bi-dentate ligand derived from Astrea’s Mimetic Ligand™ technology and is coupled to our proprietary PuraBead® 6XL base matrix which binds in a spatially selective and optimal manner to the LPS molecule. EtoxiClear™ can also remove endotoxin from a range of buffer solutions including PBS and other balanced salt solutions used in cell culture.

Key features of Etoxiclear™:

  • Specifically designed for Endotoxin removal
  • Cost effective and scalable solution
  • Suitable for use in GMP environments
  • High endotoxin dynamic binding capacity (> 1,000,000 EU/ml)
  • Compatible with wide range of proteins
  • Low protein binding (typically >90% recovery)
  • Highly stable, synthetic, non-toxic affinity ligand

Etoxiclear™ for Endotoxin Removal