ABSTRACT
OBJECTIVE:To prepare bovine serum albumin(BSA)liposomes coated with N-trimethyl chitosan(TMC) and study the factors influencing the quality of the preparation.METHODS:BSA liposomes were prepared by the method of reverse-phase evaporation.TMC polymers for coating liposomes were synthesized by quaternary amination reaction between chitosan and methyl iodide.The TMC-coated BSA liposomes were prepared.The entrapment efficiency of BSA liposomes was determined by high speed centrifugation-Coomassie brilliant blue G-250 dye method.The effects of the composition ratio of soybean lecithin(PC):cholesterol(CH):phospbatidylserine(PS),the mass ratio of TMC to total lipid and the ionic strength on particle size and entrapment efficiency were investigated.RESULTS:All the factors investigated had influences on particle size and entrapment efficiency.The optimal formulation was as follows:PC:CH:PS was 8:9:1,TMC to lipid phase ratio was 0.25:1 and ionic strength was less than 20 mmol?L~(-1).The entrapment efficiency prepared in the above conditions was (46.82?2.07)%.CONCLUSION:The TMC-coated BSA liposomes were obtained successfully and the preparation had uniform particle size and good stability.