Abstract:

To enhance the stability of salidroside liposomes, freeze-drying method was used to prepare salidroside proliposomes. The particle morphology, size distribution and encapsulation efficiency of salidroside liposomes before freezedrying and after rehydration were studied in order to evaluate the protective effects of cryoprotectants. Mannitol was the optimal cryprotectant to prepare salidroside proliposomes. Salidroside proliposomes prepared with the mass ratio of mannitol to phospholipids of 20:1 looked plumpy and compact, the encapsulation efficiency reached above 40% after rehydration, its retention rate was higher than 90%, and the average particle size of salidroside liposomes after rehydration was 223.9 nm, which was similar to that of samples before freeze-drying. Fourier transform infrared (FTIR) spectral analysis indicated that mannitol and polar group of lipid formed hydrogen bonds which could protect the integrality of liposome membrane from being destroyed during freeze-drying.

Key words: salidroside, proliposomes, freeze-drying, cryoprotectant