Enhanced protein loading into liposomes by the multiple crossflow injection technique.
Methods for encapsulation of a drug into liposomes should preferably result in a high encapsulation efficiency and a high encapsulation capacity. Our studies were focussed on the establishment of an efficient encapsulation procedure of the radical scavenging protein, rh-Cu/Zn-SOD, into liposomes with the cross flow injection method. Limitations to increase the encapsulation efficiency are caused by the enclosed aqueous volume, by the lipid concentration, the aspired vesicle size and the final ethanol concentration. Our research was performed to maximize the encapsulation following several strategies of injecting higher lipid concentrations into the aqueous phase. The one way triple technique, a sophisticated preparation procedure is presented, which enables three times higher encapsulation rates in comparison to standard procedures. Additionally, scalability studies demonstrate reproducibility independent of the preparation volume. Vesicle size distribution and encapsulation efficiency remain constant. Furthermore, special attention is paid on reproducibility of prepared liposomes, scale-up and on long term stability of the lipid vesicles.
Wagner
Andreas
A
Institute of Applied Microbiology, University of Agricultural Sciences, A-1190 Vienna, Austria. wagner@edv2.boku.ac.at
Vorauer-Uhl
Karola
K
Kreismayr
Günther
G
Katinger
Hermann
H
D015060:1,2-Dipalmitoylphosphatidylcholine / Q000737:chemistry; D000588:Amines / Q000737:chemistry; D002021:Buffers; D002626:Chemistry, Pharmaceutical; D002784:Cholesterol / Q000737:chemistry; D003300:Copper / Q000737:chemistry; D004337:Drug Carriers / Q000737:chemistry; D004355:Drug Stability; D004867:Equipment Design; D004926:Escherichia coli / Q000235:genetics; D006801:Humans; D008081:Liposomes / Q000032:analysis / Q000737:chemistry*; D011994:Recombinant Proteins / Q000737:chemistry; D015203:Reproducibility of Results; D013482:Superoxide Dismutase / Q000032:analysis / Q000737:chemistry*; D013678:Technology, Pharmaceutical; D015032:Zinc / Q000737:chemistry
D000588:Amines; D002021:Buffers; D004337:Drug Carriers; D008081:Liposomes; D011994:Recombinant Proteins; D015060:1,2-Dipalmitoylphosphatidylcholine; D003300:Copper; D002784:Cholesterol; D013482:Superoxide Dismutase; C009317:stearylamine; D015032:Zinc