Abstract:

Lactoferrin–chromium complexes were prepared by complexation of lactoferrin with chromium trichloride. The optimal complexation conditions between either ferric lactoferrin or apo-lactoferrin and Cr3+ were studied. The complexes formed were structurally characterized by infrared spectroscopy and analyzed for the contents of Fe3+ and Cr3+ by flame atomic absorption spectroscopy. Results showed that a maximum chromium saturation point of more than 90% was achieved through the complexation reaction between ferric lactoferrin and Cr3+ for more than 2 h at 50－60 ℃ and pH 6.5－7.5 and the complexation reaction between apo-lactoferrin and Cr3+ for more than 2 h at 50－65 ℃ and pH 6.0－7.5 gave a maximum chromium saturation point of close to 100%. Therefore, apo-lactoferrin is more suitable for preparation of lactoferrin-chromium complex.

Key words: lactoferrin, chromium trichloride, lactoferrin-chromium complex, preparation