Submicrogram quantitation of an acidic polysaccharide by rocket immunoelectrophoresis and rocket affinoelectrophoresis

Rocket immunoelectrophoresis has been used to quantitate an acidic polysaccharide (a succinylated lipomannan) isolated from the membranes of the bacterium, Micrococcus lysodeikticus. This procedure is superior in sensitivity to standard colorimetric assays for carbohydrate and allows the detection of as little as 10 ng of mannan. The observed relationships between rocket height and both antibody and antigen concentrations follow those described by Weeke for protein antigens Weeke, B. (1973)Scand. J. Immunol.2, Suppl. 1, 37–46]. Furthermore, the lectin concanavalin A could be used as an alternative to immune serum in the quantitation of this polysaccharide by rocket electrophoresis. However, this modification (rocket affinoelectrophoresis) appeared to be less sensitive than rocket immunoelectrophoresis, allowing the detection of about 25 ng of mannan.