title: Solidification of liposomes by freeze-drying: the importance of incorporating gelatin as interior support on enhanced physical stability.
abstract: The main purpose of this study was to investigate the effect of gelatin as interior support on the physical stability of freeze-dried liposomes. Anticancer agent paclitaxel (PTX) was selected as a model drug. Freeze-dried liposomes containing interior gelatin support (GLs) were prepared by thin-film dispersion/freeze-drying method. Several properties of the GLs, including entrapment efficiency, particle size and gelation temperature, were extensively characterized. Encapsulation efficiency of conventional liposomes (CLs) and liposomes containing lyoprotectants as interior support dropped to lower than 20% after reconstitution, while GLs still maintained an entrapment efficiency of over 84%. Scanning electron microscopy revealed well preserved liposomal structure of GLs after reconstitution. Meanwhile, the particle size and entrapment efficiency of GLs were also well preserved after reconstitution. In contrary, deformation of CLs and recrystallization of PTX were observed, as well as significant changes in particle size and entrapment efficiency. Taken together, interior gelatin support obviously enhanced the physical stability of liposomes against the lyophilization stress.
authors.affiliation: School of Pharmacy, Fudan University, Shanghai 201203, PR China; College of Life and Health Sciences, Northeastern University, Shenyang 100819, PR China.
authors.forename: Peipei
authors.initials: P
authors.lastname: Guan
authors.affiliation: School of Pharmacy, Fudan University, Shanghai 201203, PR China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Lu
authors.affiliation: School of Pharmacy, Fudan University, Shanghai 201203, PR China.
authors.forename: Jianping
authors.initials: J
authors.lastname: Qi
authors.affiliation: School of Pharmacy, Fudan University, Shanghai 201203, PR China.
authors.forename: Mengmeng
authors.initials: M
authors.lastname: Niu
authors.affiliation: School of Pharmacy, Fudan University, Shanghai 201203, PR China.
authors.forename: Ruyue
authors.initials: R
authors.lastname: Lian
authors.affiliation: School of Pharmacy, Fudan University, Shanghai 201203, PR China. Electronic address: wuwei@shmu.edu.cn.
authors.forename: Wei
authors.initials: W
authors.lastname: Wu
mesh_terms: D000972:Antineoplastic Agents, Phytogenic / Q000737:chemistry; D004339:Drug Compounding; D065546:Drug Liberation; D004355:Drug Stability; D005612:Freeze Drying; D005780:Gelatin / Q000737:chemistry*; D008081:Liposomes / Q000737:chemistry*; D017239:Paclitaxel / Q000737:chemistry; D050257:Tubulin Modulators / Q000737:chemistry
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D008081:Liposomes; D050257:Tubulin Modulators; D005780:Gelatin; D017239:Paclitaxel
keywords: Freeze-drying; Gelatin; Gelliposomes; Liposomes; Paclitaxel; Stability