메뉴 건너뛰기




Volumn 100, Issue 32, 1996, Pages 13844-13856

Interaction, lipid exchange, and effect of vesicle size in systems of oppositely charged vesicles

Author keywords

[No Author keywords available]

Indexed keywords


EID: 0000460872     PISSN: 00223654     EISSN: None     Source Type: Journal    
DOI: 10.1021/jp960327f     Document Type: Article
Times cited : (47)

References (64)
  • 1
    • 85033051749 scopus 로고    scopus 로고
    • note
    • Abbreviations: CC, charged component; Chol, cholesterol; DOD-AB, dioctadecylammonium bromide; DPA, dipicolinic acid; EPC, egg yolk lecithin; LUV, large unilamellar vesicles; NBD-PE, N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl) phosphatidylethanolamine; RET, resonance energy transfer; REV, vesicles prepared by the reverse phase method; Rh-PE, N-(Lissamine rhodamine B sulfonyl)phosphatidylethanolamine; TNS, 2-(p-toluidino)-naphthalene-6-sulfonic acid.
  • 26
    • 0345765248 scopus 로고
    • New, R. R. C., Ed.; Oxford University Press: New York
    • Liposomes, A Practical Approach; New, R. R. C., Ed.; Oxford University Press: New York, 1990.
    • (1990) Practical Approach
    • Liposomes, A.1
  • 37
    • 85033069888 scopus 로고    scopus 로고
    • note
    • α was introduced as a measure of the titration extent. Initially, α = 0, and at equivalence, α = 1.
  • 39
    • 85033063897 scopus 로고    scopus 로고
    • note
    • A relatively high ionic strength ensures that the pH sensed close to charged membrane surfaces is similar to the pH in the bulk solution.
  • 43
    • 85033046551 scopus 로고    scopus 로고
    • note
    • This simulation is based on emission measured after addition of aliquots of Rh-PE-containing vesicles to isoosmolar glucose solutions.
  • 52
    • 85033065149 scopus 로고    scopus 로고
    • note
    • By taking into account average vesicular diameters and the respective internal cesium concentrations of initially negatively and positively charged vesicles, one should expect by fusion a new NMR peak at about 1.4 ppm. For the purpose of clarity, the interpretation of the peak at 1.18 ppm will be given in the following paragraphs.
  • 56
    • 85033069926 scopus 로고    scopus 로고
    • note
    • Some remaining detergent should have played a role in the exchange process. In fact, we did not detect any significant amount of octylglucopyranoside, if any, during analysis of membrane composition. Furthermore, we reproduced Rh-PE and TNS titrations with REV prepared in the absence of detergent and DD LUV-like observations were made.
  • 58
    • 85033051884 scopus 로고    scopus 로고
    • note
    • The following discussion assumes that fluorescent probes do not induce any change of the mechanism of vesicle interaction. All experiments are thus expected to provide a coherent picture.
  • 59
    • 0020481608 scopus 로고
    • Reported results on PE fluorescent probes suggest that the surface charge of bilayers does not introduce dramatic changes of partition coefficients. See: Nichols, J. W.; Pagano, R. E. Biochemistry 1982, 21, 1720.
    • (1982) Biochemistry , vol.21 , pp. 1720
    • Nichols, J.W.1    Pagano, R.E.2
  • 61
    • 85033035623 scopus 로고    scopus 로고
    • note
    • Indeed, phosphate lipids are expected to transport cations through bilayers by flip-flop of the neutral ion pair. The difference in behavior between positively and negatively charged vesicles in the leakage rate is explained since it is known that cation exit constitutes the rate-limiting step of passive leakage of salts contained in vesicles.
  • 62
    • 85033048216 scopus 로고    scopus 로고
    • note
    • The ratio of compartmented volumes is proportional to the ratio of vesicle diameters since lipid concentrations and vesicle structures are identical for both populations of vesicles.
  • 64
    • 85033058861 scopus 로고    scopus 로고
    • note
    • The decreasing branch of the titration curve is explained by considering that already one-time neutralized vesicles become neutral after subsequent collisions with the positively charged titrating vesicles. Figure 4 suggests the Rh-PE fluorescence emission in EPC or negatively charged vesicles to be similar. Nevertheless, one cannot exclude some marginal EPC hydrolysis to yield a negatively charged surface. In a true neutral environment, Rh-PE should give an intermediate signal between positively and negatively charged vesicles.


* 이 정보는 Elsevier사의 SCOPUS DB에서 KISTI가 분석하여 추출한 것입니다.