Abstract:ObjectiveTo study the effects of freeze-drying on the endcapsulation and vesicles size of HB liposome with different kinds of lyoprotectents at various concentrations.MethodsSixteen formulations of HB liposome were designed.The entrapment efficiency was examined by fluorospectrophotometry.The particle size of the preparation was examined by microscope and digital imaging analysis software.The optimized lyoprotectent was selected based on the comparison of entrapment efficiency and particle size before and after freeze-drying.ResultsThe use of sucrose as a primary lyoprotectent and glycine as a supporting lyoprotectents and the use of mannitol provided the highest encapsulation rate and minimal change of HB liposomes.The results showed that the optimum formula were Man∶PC∶CH∶HB = 4∶1∶0.5∶0.2; Suc∶Gly∶PC∶CH∶HB = 4∶0.8∶1∶0.5∶0.2,the encapsulation rates were 69.91% and 66.70%.ConclusionThe lyoprotectent can protect the liposome vesicles during freeze-drying and mininal the influences of encapsulation and particle size.
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