A novel spectropolarimeter for determiation of sucrose and other optically active samples.

Polarimetry and spectropolarimetry are important tools in the sugar industry and pharmaceutical research. Polarimetric measurements cannot be performed on colored samples because the presence of color interferes with the final reading. To avoid the effect of color in sugar samples, lead subacetate is added. Its use to decolorize sugar is problematic because lead is a pollutant. In this work, a novel spectropolarimeter based on an ordinary spectrophotometer is described for determination of sucrose and other optically active samples. The instrument has no moving parts, and optical rotation is encoded as apparent absorbance which makes it suitable for colored samples. Background correction before apparent absorbance measurements, combined with multivariate statistical analysis over a wide spectral range, proved efficient to avoid chemical pretreatment of the samples. The instrument showed good performance for sucrose predictions and multivariate enantiomeric discrimination.