1993 Volume 16 Issue 11 Pages 1065-1068
We describe a method for the removal of endotoxins from various crude antigen solutions originating from gram-negative bacteria using aminated poly(γ-methyl L-glutamate) (PMLG) spherical particles. The aminated PMLG adsorbents showed high affinity for various purified endotoxins at an ionic strength of μ=0.1. The endotoxin-adsorbing capacity of the adsorbent increased with increase in the amino-group content of the adsorbent. The adsorbent (3.2 meq/g amino-group content) showed the highest affinity for endotoxin at ionic strengths ranging from μ=0.025-0.8. The adsorption of Bordetella pertussis antigen to the adsorbent decreased with increasing amino-group content of the adsorbent at an ionic strength of μ=0.2. The adsorption of B. bronchiseptica protein to the adsorbent increased with increasing amino-group content of the adsorbent, but decreased with increasing ionic strength. The adsorbent (3.2 meq/g of amino-group content) selectively reduced endotoxin in crude antigen solutions originating from gram-negative bacteria, B. pertussis, B. bronchiseptica and Pasteurella multocida, even at a high ionic strength (μ=0.2-0.4) without affecting the recovery of the protective antigens.