European Biophysics Journal

, Volume 35, Issue 6, pp 477–493 | Cite as

What can we learn about the lipid vesicle structure from the small-angle neutron scattering experiment?

  • M. A. Kiselev
  • E. V. Zemlyanaya
  • V. K. Aswal
  • R. H. H. Neubert


Small-angle neutron scattering (SANS) on the unilamellar vesicle (ULV) populations (diameter 500 and 1,000 Å) in D2O was used to characterize lipid vesicles from dimyristoylphosphatidylcholine (DMPC) at three phases: gel Lβ′, ripple Pβ′ and liquid Lα. Parameters of vesicle populations and internal structure of the DMPC bilayer were characterized on the basis of the separated form factor (SFF) model. Vesicle shape changes from nearly spherical in the Lα phase to elliptical in the Pβ′ and Lβ′ phases. This is true for vesicles prepared via extrusion through pores with the diameter 500 Å. Parameters of the internal bilayer structure (thickness of the membrane and the hydrophobic core, hydration and the surface area of the lipid molecule) were determined on the basis of the hydrophobic–hydrophilic (HH) approximation of neutron scattering length density across the bilayer ρ(x) and of the step function (SF) approximation of ρ(x). DMPC membrane thickness in the Lα phase (T=30°C) demonstrates a dependence on the membrane curvature for extruded vesicles. Prepared via extrusion through 500 Å diameter pores, vesicle population in the Lα phase has the following characteristics: average value of minor semi-axis 266±2 Å, ellipse eccentricity 1.11±0.02, polydispersity 26%, thickness of the membrane 48.9±0.2 Å and of the hydrophobic core 19.9±0.4 Å, surface area 60.7±0.5 Å2 and number of water molecules 12.8±0.3 per DMPC molecule. Vesicles prepared via extrusion through pores with the diameter 1,000 Å have polydispersity of 48% and membrane thickness of 45.5±0.6 Å in the Lα phase. SF approximation was used to describe the DMPC membrane structure in Lβ′ (T=10°C) and Pβ′ (T=20°C) phases. Extruded DMPC vesicles in D2O have membrane thickness of 49.6±0.5 Å in the Lβ′ phase and 48.3±0.6 Å in the Pβ′ phase. The dependence of the DMPC membrane thickness on temperature was restored from the SANS experiment.


Phospholipids Lipid membrane Vesicles Small-angle neutron scattering 













Small-angle neutron scattering


Small-angle X-ray scattering


Step function




Separated form factor


Hollow sphere


Unilamellar vesicles


Multilamellar vesicles


Differential scanning calorimetry


Gel phase


Ripple phase


Liquid crystalline phase



This work is partly based on the experiments performed at Swiss spallation neutron source SINQ, Paul Scherrer Institute, Villigen, Switzerland. The authors are grateful to V.L. Aksenov for his support, H. Schmiedel and A.M. Balagurov for fruitful discussions and K. Schwarz for performing DSC measurements. The investigation was supported by Grant of Leading Scientific Scholl, Grant of the Federal State of Saxony-Anhalt (project no. 3482A/1102L) and RFBR (grant no. 03-01-00657). The authors would like to thank Lipoid (Moscow) for the gift of DMPC.


  1. Armen PS, Uitto OD, Feller SE (1998) Phospholipid component volumes: determination and application to bilayer structure calculations. Biophys J 75:734–744PubMedGoogle Scholar
  2. Balgavy P, Dubnickova M, Uhrikova D, Yaradaikin S, Kiselev M, Gordeliy V (1998) Bilayer thickness in unilamellar extruded egg yolk phosphatidylcholine liposomes: a small-angle neutron scattering study. Acta Phys Slovaca 48:509–533Google Scholar
  3. Balgavy P, Dubnickova M, Kucerka N, Kiselev MA, Yaradaikin SP, Uhrikova D (2001) Bilayer thickness and lipid interface area in unilamellar extruded 1,2-diacylphosphatidylcholine liposomes: a small-angle neutron scattering study. Biochim Biophys Acta 1521:40–52Google Scholar
  4. Cevc G, Schatzlein A, Richardsen H (2002) Ultradiformable lipid vesicles can penetrate the skin and other semi-permiable barriers unfragmented. Evidence from double label SLSM experiments and direct size measurements. Biochim Biophys Acta 1564:21–30PubMedCrossRefGoogle Scholar
  5. Dymov SN, Kurbatov VS, Silin IN, Yaschenko SV (2000) Constrained minimization in C++ environment. Nucl Instrum Methods Phys Res A 440:431–437CrossRefADSGoogle Scholar
  6. Eadie WT, Dryan D (1971) Statistical methods in experimental physics. North-Holland, NetherlandszbMATHGoogle Scholar
  7. Feigin LA, Svergun DI (1987) Structure analysis by small-angle X-ray and neutron scattering. Plenum, New YorkGoogle Scholar
  8. Glatter O (1977) Data evaluation in small angle scattering: calculation of the radial electron density distribution by means of indirect Fourier transformation. Acta Phys Austriaca 47:83–102Google Scholar
  9. Glatter O (1980) Evaluation of small-angle scattering data from lamellar and cylindrical particles by the indirect transformation method. J Appl Crystallogr 13:577–584CrossRefGoogle Scholar
  10. Gordeliy VI, Kiselev MA (1995) Definition of lipid membrane structural parameters from neutronographic experiments with the help of the strip function model. Biophys J 69:1424–1428PubMedGoogle Scholar
  11. Gordeliy VI, Golubchikova LV, Kuklin AI, Syrykh AG, Watts A (1993) The study of single biological and model membranes via small angle neutron scattering. Prog Colloid Polym Sci 92:252–257CrossRefGoogle Scholar
  12. Gordeliy VI, Cherezov V, Teixeira J (2005) Strength of thermal undulations of phospholipid membranes. Phys Rev E 72:061913CrossRefADSGoogle Scholar
  13. Guinier A, Fournet G (1955) Small-angle scattering of X-rays. Wiley, New YorkGoogle Scholar
  14. Hallet FR, Watton J, Krygsman P (1991) Vesicle sizing. Number distributions by dynamic light scattering. Biophys J 59:357–362Google Scholar
  15. Ibel K, Stuhrmann HB (1975) Comparison of neutron and x-ray scattering of dilute myoglobin solutions. J Mol Biol 93:255–265CrossRefPubMedGoogle Scholar
  16. Jin AJ, Huster D, Gawrisch K, Nossal R (1999) Light scattering characterization of extruded lipid vesicles. Eur Biophys J 28:187–199CrossRefPubMedGoogle Scholar
  17. Kiselev MA, Lesieur P, Kisselev AM, Lombardo D, Killany M, Lesieur S (2001) Sucrose solutions as prospective medium to study the vesicle structure: SAXS and SANS study. J Alloys Compd 328:71–76CrossRefGoogle Scholar
  18. Kiselev MA, Lesieur P, Kisselev AM, Lombardo D, Aksenov VL (2002) Model of separated form factors for unilamellar vesicles. J Appl Phys A 74(Suppl):S1654–S1656CrossRefADSGoogle Scholar
  19. Kiselev MA, Lombardo D, Kisselev AM, Lesieur P, Aksenov VL (2003a) Structure factor of dimyristoylphosphatidylcholine unilamellar vesicles: small-angle X-ray scattering study (in Russian). Surf X-Ray Synchrotron Neutron Res 11:20–24Google Scholar
  20. Kiselev MA, Wartewig S, Janich M, Lesieur P, Kiselev AM, Ollivon M, Neubert R (2003b) Does sucrose influence the properties of DMPC vesicles? Chem Phys Lipids 123:31–44CrossRefGoogle Scholar
  21. Kiselev MA, Zemlyanaya EV, Aswal VK (2004) SANS study of unilamellar DMPC vesicles: fluctuation model of a lipid bilayer. Crystallogr Rep 49(Suppl 1):s136–s141Google Scholar
  22. Kiselev MA, Zbytovska J, Matveev D, Wartewig S, Gapienko IV, Perez J, Lesieur P, Hoell A, Neubert R (2005a) Influence of trehalose on the structure of unilamellar DMPC vesicles. J Colloid Surf A Physicochem Eng Aspects 256:1–7CrossRefGoogle Scholar
  23. Kiselev MA, Ryabova NY, Balagurov AM, Dante S, Hauss T, Zbytovska J, Wartewig S, Neubert RHH (2005b) New insights into structure and hydration of stratum corneum lipid model membrane by neutron diffraction. Eur Biophys J 34:1030–1040CrossRefGoogle Scholar
  24. Knoll W, Haas J, Stuhrmann H, Fuldner HH, Vogel H, Sackmann E (1981) Small-angle neutron scattering of aqueous dispersions of lipids and lipid mixtures A contrast variation study. J Appl Crystallogr 14:191–202CrossRefGoogle Scholar
  25. Kobayashi Y, Fukado K (1998) The lamellar repeat distance of phospholipid bilayers in excess H2O and D2O. A small-angle X-ray scattering study. Chem Lett:1105–1106Google Scholar
  26. Korgel B, van Zanten JH, Monbouquette HG (1998) Vesicle size distributions measured by flow field-flow fractionation. Biophys J 74:3264–3272PubMedGoogle Scholar
  27. Kucerka N, Uhrikova D, Teixeira J, Balgavy P (2004a) Bilayer thickness in unilamellar phosphatidylcholine vesicles: small-angle neutron scattering using contrast variation. Physica B 350:e639–e642CrossRefADSGoogle Scholar
  28. Kucerka N, Kiselev MA, Balgavy P (2004b) Determination of bilayer thickness and lipid surface area in unilamellar dimyristoylphosphatidylcholine vesicles from small-angle neutron scattering curves: a comparison of evaluation methods. Eur Biophys J 33:328–334CrossRefGoogle Scholar
  29. Kucerka N, Nagle JF, Feller SF, Balgavy P (2004c) Models to analyze small-angle neutron scattering from unilamellar lipid vesicles. Phys Rev E 69:051903CrossRefADSGoogle Scholar
  30. Kucerka N, Liu Y, Chu N, Petrache HI, Tristram-Nagle S, Nagle JF (2005) Structure of fully hydrated fluid phase DMPC and DLPC lipid bilayers using X-ray scattering from oriented multilamellar arrays and from unilamellar vesicles. Biophys J 88:2626–2637CrossRefPubMedGoogle Scholar
  31. MacDonald RC, MacDonald RI, Menco BP, Takeshita K, Subbarao NK, Hu LR (1991) Small-volume extrusion apparatus for preparation of large, unilamellar vesicles. Biochim Biophys Acta 1061:297–303PubMedCrossRefGoogle Scholar
  32. Matsuki H, Okuno H, Sakano F, Kusube M, Kaneshina S (2005) Effect of deuterium oxide on the thermodynamic quantities associated with phase transitions of phosphatidylcholine bilayer membranes. Biochim Biophys Acta 1712:92–100PubMedCrossRefGoogle Scholar
  33. Nagayasu A, Uchiyama K, Kiwada H (1999) The size of liposomes: a factor which affects their targeting efficiency to tumors and therapeutics activity of liposomal antitumor drugs. Adv Drug Deliv Rev 40:75–87CrossRefPubMedGoogle Scholar
  34. Nagle JF, Tristram-Nagle S (2000) Structure of lipid bilayers. Biochim Biophys Acta 1469:159–195PubMedGoogle Scholar
  35. Ostanevich YuM (1988) Time-of-flight small-angle scattering spectrometers on pulsed neutron sources. Macromol Chem Macromol Symp 15:91–103Google Scholar
  36. Patty PJ, Frisken BJ (2003) The pressure-dependence of the size of extruded vesicles. Biophys J 85:996–1004PubMedGoogle Scholar
  37. Pedersen JS, Posselt D, Mortensen K (1990) Analytical treatment of the resolution function for small-angle scattering. J Appl Crystallogr 23:321–333CrossRefGoogle Scholar
  38. Pencer J, Hallet R (2000) Small-angle neutron scattering from large unilamellar vesicles: an improved method for membrane thickness determination. Phys Rev E 61:3003–3008CrossRefADSGoogle Scholar
  39. Pencer J, White GF, Hallet FR (2001) Osmotically induced shape changes of large unilamellar vesicles measured by dynamic light scattering. Biophys J 81:2716–2728PubMedGoogle Scholar
  40. Rappolt M, Pabst G, Rapp G, Kriechbaum M, Amenitsch H, Krenn C, Bernstorff S, Laggner P (2000) New evidence for gel–liquid crystalline phase coexistence in the ripple phase of phosphatidylcholines. Eur Biophys J 29:125–133CrossRefPubMedGoogle Scholar
  41. Ruocco MJ, Shipley GG (1982) Characterization of the sub-transitions of hydrated dipalmitoylphosphatidylcholine bilayers. Kinetics, hydration and structural study. Biochim Biophys Acta 691:309–320CrossRefGoogle Scholar
  42. Schalke M, Kruger P, Weygand M, Losche M (2000) Submolecular organization of DMPA in surface monolayers: beyond the two-layer model. Biochim Biophys Acta 1464:113–126PubMedCrossRefGoogle Scholar
  43. Schmiedel H, Joerchel P, Kiselev M, Klose G (2001) Determination of structural parameters and hydration of unilamellar POPC/C12E4 vesicles at high water excess from neutron scattering curves using a novel method of evaluation. J Phys Chem B 105:111–117CrossRefGoogle Scholar
  44. Schmiedel H, Almasy L, Klose G (2005) Multilamellarity, structure and hydration of extruded POPC vesicles by SANS. Eur Biophys J:s00249-005-0015-9, online firstGoogle Scholar
  45. Sun WJ, Tristram-Nagle S, Suter RM, Nagle JF (1996) Structure of the ripple phase in lecithin bilayers. Proc Natl Acad Sci USA 93:7008–7012CrossRefPubMedADSGoogle Scholar
  46. Tokutake N, Jing B, Regen SL (2004) Probing the hydration of lipid bilayers using a solvent isotope effect on phospholipid mixing. Langmuir 20:8958–8960CrossRefPubMedGoogle Scholar
  47. Tristram-Nagle S, Liu Y, Legleiter J, Nagle JF (2002) Structure of gel phase DMPC determined by X-ray diffraction. Biophys J 83:3324–3335PubMedGoogle Scholar
  48. Weiss TM, Narayanan T, Wolf C, Gradzielski M, Panine P, Finet S, Helsby WI (2005) Dynamics of the self-assembly of unilamellar vesicles. Phys Rev Lett 94:038303CrossRefPubMedADSGoogle Scholar
  49. Wiener MC, White SH (1991) Fluid bilayer structure determination by the combined use of X-ray and neutron diffraction. Biophys J 59:162–173PubMedCrossRefGoogle Scholar

Copyright information

© EBSA 2006

Authors and Affiliations

  • M. A. Kiselev
    • 1
  • E. V. Zemlyanaya
    • 2
  • V. K. Aswal
    • 3
  • R. H. H. Neubert
    • 4
  1. 1.Frank Laboratory of Neutron PhysicsJoint Institute for Nuclear ResearchDubnaRussia
  2. 2.Laboratory of Information TechnologiesJoint Institute for Nuclear ResearchDubnaRussia
  3. 3.Solid State Physics DivisionBhabha Atomic Research CentreMumbaiIndia
  4. 4.Institute of Pharmaceutical Technology and BiopharmacyMartin-Luther-UniversityHalle (Saale)Germany

Personalised recommendations