Counterimmunoelectrophoresis of pneumococcal antigens:improved sensitivity for the detection of types VII and XIV

Rapid identification of Streptococcus pneumoniae has been reported using counterimmunoelectrophoresis for the detection of specific capsular antigens in serum, cerebrospinal fluid, and urine. Previous clinical studies have failed to detect type VII or XIV pneumococcal antigen. These two types, however, account for a significant portion of pneumococcal disease. The incorporation of a sulfonated derivative of phenylboronic acid in the buffer system provides a method for the sensitive detection of these types in artificial mixtures without greatly reducing the sensitivity for the detection of other pneumococcal types. A problem with false positives encountered using human serum and barbitalbuffer was reduced by the use of buffer containing sulfonated phenylboronic acid.