Abstract:

A HPLC method was developed for the determination of lactoferrin in dairy products. Lactoferrin was easier to precipitate by the introduction of additional ferrous ion and 60% ethanol solution was added to precipitate proteins for removing carbohydrates. The precipitate, whose main composition was lactoferrin, was extracted with acetic acid buffer to remove casein impurity prior to HPLC analysis. The chromatographic separation was achieved on a LiChrosorb RP-C18 column using single 0.1 g/100 mL TFA as mobile phase A and a mixture of 98% methanol and 0.1 g/100 mL TFA as mobile phase B and linear gradient elution mode was used. This method exhibited a good linearity over the concentration range of 0.4 to 2 mg/mL for lactoferrin in dairy products (R2 = 0.9980), and the average recovery for lactoferrin at five spike levels was 95.4%.

Key words: lactoferrin, milk products, HPLC