[Preparation of interferon-alpha-containing liposomes by the powder bed grinding method]

OBJECTIVE: To investigate a nwe, simple technique for preparation of interferon-alpha-liposomes, which may be suitable for industrial use. METHODS The uniform design coupled with computerized optimization was utilized to screen the formulation and preparation procedure of interferon-alpha-liposomes. Pro-liposomes were prepared by the powder bed grinding method and combined with interferon-alpha-solution to form interferon-alpha-liposomes. Liposome size was determined by the particle size analyzer. Free interferon-alpha and interferon-alpha-liposome were separated by gel filtration. Then the recovered activity of interferon-alpha was analyzed by enzyme-linked immunosorbent assay. RESULTS The result demonstrated that the best interferon-alpha-liposome formulation was as follows: the protectant was sorbitol; weight ratio of protectant to lipid was 5:1; weight ratio of octadecytamin to lipid was 1:9; weight ratio of sobey phosphatidylcholine to cholesterol was 9:1 respectively. Interferon-alpha-liposome size determined by the particle size analyzer was 80.8+/-36 nm and the encapsulation efficiency was 59.0+/-3.3%. CONCLUSION The powder bed grinding method can be used to prepare pro-liposomes which can be easily combined with interferon-alpha-solution to form interferon-alpha-liposomes.