Binding of Brucella abortus whole cell and lipopolysaccharide antigens to plastics

Various buffers (0.2 M acetate, pH 4.2; 0.01 M phosphate with 0.15 M sodium chloride, pH 7.2; 0.15 M borate, pH 8.2 and 0.025 M carbonate, pH 9.6) were used as coating buffers with Brucella abortus alkali treated lipopolysaccharide on two types of plastic matrices. Maximum binding occurred using the phosphate buffer. However, as was the case with the other buffers 50 per cent or more of the antigen was removed by five washing procedures. B abortus S19 or S2308, suspended in ammonium acetate-carbonate buffer, pH 8.2, was shown to bind maximally when 10(9) cells were dried onto the plastics. Less than 20 per cent of the cells were removed by five washings.