Optimization of Preparation Technology of Tetracaine Hydrochloride Ethosomes / 中国药房

ABSTRACT

OBJECTIVE： To establish a method for determining the content of tetracaine hydrochloride （TCH） ethosomes， and to optimize the preparation technology. METHODS： The content of TCH was determined by HPLC. TCH ethosomes were prepared with injection-ultrasonic method. Using drug-loading amount， egg lecithin concentration and ethanol volume fraction as factor， encapsulation efficiency as index， central composite design-response surface methodology was used to optimize the prescription based on the single factor test. The prepared ethosomes were characterized and the stability was evaluated. RESULTS： The linear range of TCH was 10-100 μg/mL （r＝0.999 5）； the limit of quantification was 0.045 μg/mL， and detection limit was 0.021 μg/mL. RSD of precision， stability and repeatability tests were less than 2％. The recoveries ranged 97.80％-103.20％ （RSD＝0.36％， n＝9）. The optimal preparation technology included that the adding amount of TCH control was 1 mg； the concentration of egg lecithin was 7 mg/mL， and ethanol volume fraction was 33％. Under this technology， the average encapsulation efficiency was 64.50％ （n＝3）， the relative error of which from the predicted value （64.92％） was 0.64％. TCH ethosome was a clear blue liquid with a blue opalescence. Its appearance was spherical， its shape was round， smooth， uniform in size； the average particle size was （80.33±2.24） nm， and the average Zeta potential was （－22.6±1.33） mV. TCH ethosome was stable during 10 days under 4 ℃， sealed and protected from light. CONCLUSIONS： The optimal preparation process is stable and feasible. Established method is simple and rapid.