关键词: 高效凝胶渗透色谱法, 马初乳, 免疫球蛋白G

Abstract: A direct high-performance gel permeation chromatographic (HPGPC) method for the determination of immunoglobulin G in mare colostrum was established. HPGPC separation was performed on a TOSOH TSK-G4000PWXL column (300 mm×7.8 mm, 5 μm) with 0.05 mol/L phosphate buffer solution (pH 6.9) as the mobile phase at a flow rate of 0.8 mL/min, and the column temperature was maintained at 25 ℃. The injection volume was 20 μL. At the detection wavelength of 280 nm, the linear range was from 0.2 to 3.0 g/L (r2=0.9995) with a detection limit of 0.08 mg/L (S/N=10). The recovery was 97.47% with a relative standard deviation (RSD) of 1.22%. The RSDs of the peak area of stability, accuracy and reproducibility for the established method were 2.86%, 1.62% and 1.82%, respectively. Mare milk was collected from Zhaosu (China), a complete collection was stored in an ice box, then sent to a laboratory and stored in a low temperature refrigerator. The whey milk was prepared by centrifugation two times at 12000 r/min and 4 ℃ for 30 min. The whey protein was obtained from the middle layer. A 2 mL volume of the whey milk was mixed with 23 mL of mobile phase. The average contents of IgG were from 35.0 g/L to 50.0 g/L at the first lactation (2 h), and the average contents of IgG were from 2.0 g/L to 4.0 g/L after 72 h. The relatively simple analytical method was proved to be accurate and precise in its application to mare colostrum.

Key words: immunoglobulin G, mare colostrum, high-performance gel permeation chromatography (HPGPC)