Removal of gram-negative endotoxin from solutions by affinity chromatography

Area of Science:

• Microbiology
• Biochemistry
• Analytical Chemistry

Background:

• Endotoxins from gram-negative bacteria contaminate aqueous and physiological solutions.
• These endotoxins possess potent biological effects, necessitating their removal.
• Minute quantities of endotoxin can significantly impact experimental results and biological systems.

Purpose of the Study:

• To develop an efficient method for removing endotoxins from solutions.
• To utilize the specific binding affinity of polymyxin B for endotoxin removal.
• To establish a chromatography-based technique for endotoxin purification.

Main Methods:

• Chromatography using polymyxin B Sepharose 4B was employed.
• The method exploits the high binding affinity of polymyxin B for the lipid A component of endotoxins.
• Solutions were processed under mild, physiological conditions.

Main Results:

• The described method demonstrated high effectiveness in endotoxin removal.
• Essentially complete removal of several types of endotoxins was achieved.
• The process was effective for solutions contaminated with 1-10 micrograms/ml of endotoxin, as assessed by Limulus amoebocyte lysate assay.

Conclusions:

• Polymyxin B Sepharose 4B chromatography is a simple and highly effective technique for endotoxin removal.
• This method is suitable for purifying aqueous and physiological solutions contaminated with endotoxins.
• The process operates under mild physiological conditions, preserving solution integrity.