[Comparison of refractometric and ultraviolet detection methods in lactulose assay by high performance liquid chromatography].

Dosage of lactulose and determination of related sugars (lactose, fructose, galactose, épilactose) were undertaken by high performance liquid chromatography (HPLC). The present note described two modes of detection used simultaneously and compared: refractive index detector (RI) and multiwavelength ultraviolet detector (UV). HPLC is performed with an aminopropylsylil phase as stationary phase and an isocratic mobile phase containing acetonitrile and aqueous sodium phosphate. The results are outlined and discussed.