Determination of o-toluenesulfonamide in artificial sweeteners containing saccharin.

A gas-liquid chromatographic (GLC) procedure with p-toluenesulfonamide (p-TS) as an internal standard is used to determine o-toluenesulfonamide (o-TS), a major impurity in artificial sweetening substances containing saccharin. Although p-TS can itself occur as an impurity in samples, it is usually absent or present in very small amounts; the highest quantity found in 13 samples analyzed was about 1 ppm. The presence of appreciable amounts, however, would not pose a problem with the GLC procedure. Recoveries of standard o-TS added at various levels were approximately 90%.