PREPARATION OF VINORELBINE TARTRATE THERMOSENSITIVE LIPOSOMES AND MEASUREMENT OF ITS ENCAPSULATION EFFICIENCY

LIXIN LAN, QUAN ZHOU, XIAOHUI YANG

Department of Pharmaceutical and Biological Engineering, Hunan Chemical Vocational Technology College, Zhuzhou, 412004, China

Objective: This paper aims to explore the preparation of vinorelbine tartrate (VRT) thermosensitive liposomes and determine its encapsulation efficiency.

Methods: Preparation of VRT thermosensitive liposomes was carried out by pH gradient method. The VRT content in liposomes was determined by high performance liquid chromatograph (HPLC). Separation of liposomes and free drugs was done with microcolumn centrifugation method. The influence on type of dextrangel and elution solvent as well as eluted volume of vinorelbine tartrate and free drug was closely observed.

Results: The average particle size and average content of vinorelbine tartrate were (94.8 ± 1.5) nm,(1.84±0.04)mg/mL respectively. The dextrangel G-25 was used for preparation of microcolumn, in which 4 cm was the best column height. The elution solvent used was PBS buffer and gradient elution volume method was employed in separation of liposomes and free drugs. The enca- psulation efficiency of three batches vinorelbine tartrate were recorded as (95.76 ± 1.43)%, (91.13 ± 1.24)% and (94.13 ± 2.05)%, with respective elution recovery rate at (98.5 ± 2.41)%, (93.6 ± 1.85)% and 96.8 ± 1.67)%.

Conclusion: Preparation of vinorelbine tartrate is relatively a stable process technology with large drug loading, which resulted in high encapsulation efficiency. Moreover, there are accurate and convenient methods for measurements of content and encapsulation efficiency.