According to JP, analysis of lactulose should be done using a HPLC column filled with strong acid cation exchange resins. The system suitability requires to obtain their elution order to be lactulose and then the internal standard (mannitol); the resolution between them to be ≥ 8 (injection volume 10 μL); and relative standard deviation (RSD) of peak height ratios against the internal standard to be ≤ 2.0% for lactose, lactulose, and galactose (injection volume 20 μL).
SUGAR SP0810 was confirmed to satisfy all required conditions for the analysis.
Sample : 10 µL
1. Lactose 0.8 mg/mL
2. Lactulose 10 mg/mL
3. Galactose 1.6 mg/mL
4. Mannitol 10 mg/mL
*dissolved in H2O
Column : Shodex SUGAR SP0810 (8.0 mm I.D. x 300 mm) Eluent : H2O Flow rate : 0.5 mL/min Detector : Shodex RI Column temp. : 75 °C