Membrane properties of cationic liposomes composed of dipalmitoylphosphatidylcholine and dipalmityldimethylammonium bromide

Shoko Yokoyama, Akiko Inagaki, Tomohiro Imura, Takahiro Ohkubo, Nobuyuki Tsubaki, Hideki Sakai, Masahiko Abe

Research output: Contribution to journalArticle

10 Citations (Scopus)

Abstract

Cationic liposomes composed of dipalmitoylphosphatidylcholine (DPPC) and dipalmityldimethylammmonium bromide (DPAB) were prepared by the Bangham method and the effect of DPAB on the membrane properties was examined in terms of liposomal shape, particle size, trapping efficiency, surface potential and dispersibility. The dispersibility of the mixed DPPC/DPAB liposomes (the mole fraction of DPAB (XDPAB) ≧ 0.05) was excellent and the dispersibility was maintained for 6 months, since the zeta-potential of the mixed liposomes was approximately +40 mV. The trapping efficiency of the mixed DPPC/DPAB liposomes (XDPAB = 0.05) was 10 times greater than that of the DPPC liposomes, and the value was largest among the mixed liposomes (XDPAB = 0-1.0). Freeze-fracture electron micrographs indicated that the shape of the mixed DPPC/DPAB liposomes (XDPAB = 0.05) was that of large unilamellar vesicles (LUVs) with a diameter of approximately 2 μm, while the shape of the DPPC liposomes was that of multilamellar vesicles (MLVs). The mixed liposomes had, therefore, a high trapping efficiency. Furthermore, the shape of the mixed DPPC/DPAB liposomes (XDPAB = 0.75) was also that of LUVs with a diameter of approximately 2 μm and these had a high trapping efficiency. Whereas, the particle size (500 nm) of the mixed DPPC/DPAB liposomes (XDPAB = 0.25) was smaller than that of the former and had the minimum trapping efficiency. The phase transition temperature of the liposomal bilayer membranes indicated a maximum value at 0.25-0.30 mole fractions of DPAB. These facts were considered to be due to the fact that DPPC and DPAB, whose molar ratio was 7.5:2.5, were tightly packed in the liposomal bilayer membranes and that the curvature of the liposomal particle was resultantly large. Nevertheless, LUVs having a high trapping efficiency were easily obtained by mixing a small amount of DPAB with the DPPC.

Original languageEnglish
Pages (from-to)204-210
Number of pages7
JournalColloids and Surfaces B: Biointerfaces
Volume44
Issue number4
DOIs
Publication statusPublished - Sep 2005
Externally publishedYes

Fingerprint

1,2-Dipalmitoylphosphatidylcholine
Liposomes
Bromides
bromides
membranes
Membranes
trapping
Unilamellar Liposomes
Particle Size
Particle size
Transition Temperature
Phase Transition
Surface potential
Zeta potential
Superconducting transition temperature
Phase transitions
transition temperature
curvature

Keywords

  • Cationic liposomes
  • Dipalmityldimethylammonium bromide
  • Freeze-fracture electron microscopy
  • Large unilamellar vesicles
  • Trapping efficiency

ASJC Scopus subject areas

  • Biotechnology
  • Colloid and Surface Chemistry
  • Physical and Theoretical Chemistry
  • Surfaces and Interfaces

Cite this

Membrane properties of cationic liposomes composed of dipalmitoylphosphatidylcholine and dipalmityldimethylammonium bromide. / Yokoyama, Shoko; Inagaki, Akiko; Imura, Tomohiro; Ohkubo, Takahiro; Tsubaki, Nobuyuki; Sakai, Hideki; Abe, Masahiko.

In: Colloids and Surfaces B: Biointerfaces, Vol. 44, No. 4, 09.2005, p. 204-210.

Research output: Contribution to journalArticle

Yokoyama, Shoko ; Inagaki, Akiko ; Imura, Tomohiro ; Ohkubo, Takahiro ; Tsubaki, Nobuyuki ; Sakai, Hideki ; Abe, Masahiko. / Membrane properties of cationic liposomes composed of dipalmitoylphosphatidylcholine and dipalmityldimethylammonium bromide. In: Colloids and Surfaces B: Biointerfaces. 2005 ; Vol. 44, No. 4. pp. 204-210.
@article{a42395b2b0184ce59ce77a80430f151d,
title = "Membrane properties of cationic liposomes composed of dipalmitoylphosphatidylcholine and dipalmityldimethylammonium bromide",
abstract = "Cationic liposomes composed of dipalmitoylphosphatidylcholine (DPPC) and dipalmityldimethylammmonium bromide (DPAB) were prepared by the Bangham method and the effect of DPAB on the membrane properties was examined in terms of liposomal shape, particle size, trapping efficiency, surface potential and dispersibility. The dispersibility of the mixed DPPC/DPAB liposomes (the mole fraction of DPAB (XDPAB) ≧ 0.05) was excellent and the dispersibility was maintained for 6 months, since the zeta-potential of the mixed liposomes was approximately +40 mV. The trapping efficiency of the mixed DPPC/DPAB liposomes (XDPAB = 0.05) was 10 times greater than that of the DPPC liposomes, and the value was largest among the mixed liposomes (XDPAB = 0-1.0). Freeze-fracture electron micrographs indicated that the shape of the mixed DPPC/DPAB liposomes (XDPAB = 0.05) was that of large unilamellar vesicles (LUVs) with a diameter of approximately 2 μm, while the shape of the DPPC liposomes was that of multilamellar vesicles (MLVs). The mixed liposomes had, therefore, a high trapping efficiency. Furthermore, the shape of the mixed DPPC/DPAB liposomes (XDPAB = 0.75) was also that of LUVs with a diameter of approximately 2 μm and these had a high trapping efficiency. Whereas, the particle size (500 nm) of the mixed DPPC/DPAB liposomes (XDPAB = 0.25) was smaller than that of the former and had the minimum trapping efficiency. The phase transition temperature of the liposomal bilayer membranes indicated a maximum value at 0.25-0.30 mole fractions of DPAB. These facts were considered to be due to the fact that DPPC and DPAB, whose molar ratio was 7.5:2.5, were tightly packed in the liposomal bilayer membranes and that the curvature of the liposomal particle was resultantly large. Nevertheless, LUVs having a high trapping efficiency were easily obtained by mixing a small amount of DPAB with the DPPC.",
keywords = "Cationic liposomes, Dipalmityldimethylammonium bromide, Freeze-fracture electron microscopy, Large unilamellar vesicles, Trapping efficiency",
author = "Shoko Yokoyama and Akiko Inagaki and Tomohiro Imura and Takahiro Ohkubo and Nobuyuki Tsubaki and Hideki Sakai and Masahiko Abe",
year = "2005",
month = "9",
doi = "10.1016/j.colsurfb.2005.01.005",
language = "English",
volume = "44",
pages = "204--210",
journal = "Colloids and Surfaces B: Biointerfaces",
issn = "0927-7765",
publisher = "Elsevier",
number = "4",

}

TY - JOUR

T1 - Membrane properties of cationic liposomes composed of dipalmitoylphosphatidylcholine and dipalmityldimethylammonium bromide

AU - Yokoyama, Shoko

AU - Inagaki, Akiko

AU - Imura, Tomohiro

AU - Ohkubo, Takahiro

AU - Tsubaki, Nobuyuki

AU - Sakai, Hideki

AU - Abe, Masahiko

PY - 2005/9

Y1 - 2005/9

N2 - Cationic liposomes composed of dipalmitoylphosphatidylcholine (DPPC) and dipalmityldimethylammmonium bromide (DPAB) were prepared by the Bangham method and the effect of DPAB on the membrane properties was examined in terms of liposomal shape, particle size, trapping efficiency, surface potential and dispersibility. The dispersibility of the mixed DPPC/DPAB liposomes (the mole fraction of DPAB (XDPAB) ≧ 0.05) was excellent and the dispersibility was maintained for 6 months, since the zeta-potential of the mixed liposomes was approximately +40 mV. The trapping efficiency of the mixed DPPC/DPAB liposomes (XDPAB = 0.05) was 10 times greater than that of the DPPC liposomes, and the value was largest among the mixed liposomes (XDPAB = 0-1.0). Freeze-fracture electron micrographs indicated that the shape of the mixed DPPC/DPAB liposomes (XDPAB = 0.05) was that of large unilamellar vesicles (LUVs) with a diameter of approximately 2 μm, while the shape of the DPPC liposomes was that of multilamellar vesicles (MLVs). The mixed liposomes had, therefore, a high trapping efficiency. Furthermore, the shape of the mixed DPPC/DPAB liposomes (XDPAB = 0.75) was also that of LUVs with a diameter of approximately 2 μm and these had a high trapping efficiency. Whereas, the particle size (500 nm) of the mixed DPPC/DPAB liposomes (XDPAB = 0.25) was smaller than that of the former and had the minimum trapping efficiency. The phase transition temperature of the liposomal bilayer membranes indicated a maximum value at 0.25-0.30 mole fractions of DPAB. These facts were considered to be due to the fact that DPPC and DPAB, whose molar ratio was 7.5:2.5, were tightly packed in the liposomal bilayer membranes and that the curvature of the liposomal particle was resultantly large. Nevertheless, LUVs having a high trapping efficiency were easily obtained by mixing a small amount of DPAB with the DPPC.

AB - Cationic liposomes composed of dipalmitoylphosphatidylcholine (DPPC) and dipalmityldimethylammmonium bromide (DPAB) were prepared by the Bangham method and the effect of DPAB on the membrane properties was examined in terms of liposomal shape, particle size, trapping efficiency, surface potential and dispersibility. The dispersibility of the mixed DPPC/DPAB liposomes (the mole fraction of DPAB (XDPAB) ≧ 0.05) was excellent and the dispersibility was maintained for 6 months, since the zeta-potential of the mixed liposomes was approximately +40 mV. The trapping efficiency of the mixed DPPC/DPAB liposomes (XDPAB = 0.05) was 10 times greater than that of the DPPC liposomes, and the value was largest among the mixed liposomes (XDPAB = 0-1.0). Freeze-fracture electron micrographs indicated that the shape of the mixed DPPC/DPAB liposomes (XDPAB = 0.05) was that of large unilamellar vesicles (LUVs) with a diameter of approximately 2 μm, while the shape of the DPPC liposomes was that of multilamellar vesicles (MLVs). The mixed liposomes had, therefore, a high trapping efficiency. Furthermore, the shape of the mixed DPPC/DPAB liposomes (XDPAB = 0.75) was also that of LUVs with a diameter of approximately 2 μm and these had a high trapping efficiency. Whereas, the particle size (500 nm) of the mixed DPPC/DPAB liposomes (XDPAB = 0.25) was smaller than that of the former and had the minimum trapping efficiency. The phase transition temperature of the liposomal bilayer membranes indicated a maximum value at 0.25-0.30 mole fractions of DPAB. These facts were considered to be due to the fact that DPPC and DPAB, whose molar ratio was 7.5:2.5, were tightly packed in the liposomal bilayer membranes and that the curvature of the liposomal particle was resultantly large. Nevertheless, LUVs having a high trapping efficiency were easily obtained by mixing a small amount of DPAB with the DPPC.

KW - Cationic liposomes

KW - Dipalmityldimethylammonium bromide

KW - Freeze-fracture electron microscopy

KW - Large unilamellar vesicles

KW - Trapping efficiency

UR - http://www.scopus.com/inward/record.url?scp=26944472875&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=26944472875&partnerID=8YFLogxK

U2 - 10.1016/j.colsurfb.2005.01.005

DO - 10.1016/j.colsurfb.2005.01.005

M3 - Article

C2 - 16087320

AN - SCOPUS:26944472875

VL - 44

SP - 204

EP - 210

JO - Colloids and Surfaces B: Biointerfaces

JF - Colloids and Surfaces B: Biointerfaces

SN - 0927-7765

IS - 4

ER -