Determination of the Molecular Weight Distribution of Small Molecule Oligopeptide in Fish Skin Collagen Hydrolyzate

OBJECTIVE To establish a method for determining the molecular weight distribution of small molecule oligopeptide in fish skin collagen hydrolyzate. METHODS The molecular weight distribution was determined using three TSK-GEL G 2000SWXL columns (300 mm×7.8 mm, 5 μm) in series at room temperature with the mobile phase of acetonitrile-0.1% trifluoracetic acid solution (15∶85) at the flow rate of 0.6 mL·min^-1. The detection wavelength was 220 nm. RESULTS In the molecular weight range of 149-2 490 Da, there was a good linear relationship between the logarithm of molecular weight of oligopeptide and the retention time(r=0.995 6). The RSD of precision and repeatability were both less than 0.1%. CONCLUSION The method is simple, accurate and reproducible for the determination of the molecular weight distribution of small molecule oligopeptide.