Journal of Chemical Sciences

, 130:132 | Cite as

Modification of fatty acid vesicle using an imidazolium-based surface active ionic liquid: a detailed study on its modified properties using spectroscopy and microscopy techniques\(^{\S }\)

  • Shreya Roy
  • Sarthak Mandal
  • Pavel Banerjee
  • Nilmoni SarkarEmail author
Regular Article


Fatty acid vesicles have attracted views as model protocell membranes in understanding the emergence of life, but their properties can be further modified in the presence of some external molecules. In this work, we have investigated the spontaneous formation of large unilamellar vesicles (LUVs) of oleic acid in aqueous medium in presence of a popular imidazolium-based cationic surface active ionic liquid (SAIL) \([\hbox {C}_{16}\hbox {mim}]\hbox {Cl}\) and studied the micelle–vesicle transition of aqueous \([\hbox {C}_{16}\hbox {mim}]\hbox {Cl}\) solution in presence of different molar fractions (f) of oleic acid. This newly formed oleic \(\hbox {acid}/[\hbox {C}_{16}\hbox {mim}]\hbox {Cl}\) vesicles exhibit some modified properties compared to the pure fatty acid vesicles. Unlike pure fatty acid vesicles, these vesicles are stable in the pH range of 2 to 11.2. We have observed the fusion process of these oleic acid/SAIL vesicles to form giant unilamellar vesicles (GUVs) in presence of low concentration of NaCl solution. To investigate the dynamics of different oleic \(\hbox {acid}/[\hbox {C}_{16}\hbox {mim}]\hbox {Cl}\) self-assemblies, we have used fluorescence correlation spectroscopy (FCS). The translational diffusion behavior of three different dyes, Rhodamine 6G, DCM and Pyrromethene 597, which are non-covalently bound to the different regions of the oleic acid/SAIL self-assemblies, have been determined using FCS during the micelle–vesicle transition and upon varying the pH of the vesicular solution.

Graphical Abstract

Oleic acid vesicles prepared in presence of a surface active ionic liquid \([\hbox {C}_{16}\hbox {mim}]\hbox {Cl}\) have been characterized. Modified properties of these vesicles like stability towards a greater pH range as compared to pure oleic acid vesicles and fusion of vesicles in presence of low concentration of NaCl solution have been studied.


Model membrane micelle–vesicle transition single molecule spectroscopy ionic liquid fluorescence correlation spectroscopy fluorescence lifetime imaging microscopy 



N.S. gratefully acknowledges SERB, Department of Science and Technology (DST), Government of India for providing a generous research grant. S.R., S.M. and P. B. are thankful to UGC and CSIR for research fellowships. We are thankful to Dr. Niloy Kundu and Dr. Arpita Roy for helpful discussions.

Supplementary material

12039_2018_1532_MOESM1_ESM.pdf (877 kb)
Supplementary material 1 (pdf 876 KB)


  1. 1.
    Tang T-Y D, Che Hak, C R, Thompson A J, Kuimova M K, Williams D S, Perriman A W and Mann S 2014 Fatty Acid Membrane Assembly on Coacervate Microdroplets As a Step Towards a Hybrid Protocell Model Nat. Chem. 6 527CrossRefGoogle Scholar
  2. 2.
    Chen I A and Szostak J W 2004 Membrane Growth can Generate a Transmembrane pH Gradient in Fatty Acid Vesicles Proc. Natl. Acad. Sci. U.S.A.  101 7965CrossRefGoogle Scholar
  3. 3.
    Morigaki K and Szostak W 2007 Fatty Acid Vesicles Curr. Opin. Colloid Interface Sci. 12 75CrossRefGoogle Scholar
  4. 4.
    Stano P and Luisi L 2010 Achievements and Open Questions in the Self-Reproduction of Vesicles and Synthetic Minimal Cells Chem. Commun46 3639CrossRefGoogle Scholar
  5. 5.
    Szostak J W, Bartel D P and Luisi P L 2001 Synthesizing Life Nature 409 387CrossRefGoogle Scholar
  6. 6.
    Mansy S S and Szostak J W 2008 Thermostability of Model Protocell Membranes Proc. Natl. Acad. Sci. U.S.A. 105 13351CrossRefGoogle Scholar
  7. 7.
    Hanczyc M M, Fujikawa S M and Szostak J W 2003 Experimental Models of Primitive Cellular Compartments: Encapsulation, Growth, and Division Science 302 618CrossRefGoogle Scholar
  8. 8.
    Walde P and Ichikawa S 2001 Enzymes inside Lipid Vesicles: Preparation, Reactivity and Applications Biomol. Eng. 18 143CrossRefGoogle Scholar
  9. 9.
    Walde P, Wick R, Fresta M, Mangone A and Luisi P L 1994 Autopoietic Self-Reproduction of Fatty Acid Vesicles J. Am. Chem. Soc. 116 11649CrossRefGoogle Scholar
  10. 10.
    Stano P, Wehrli E and Luisi P L 2006 Insights on the Oleate Vesicles Self-Reproduction J. Phys. Condens. Matter 18 S2231CrossRefGoogle Scholar
  11. 11.
    Chen I A and Szostak J W 2004 A Kinetic Study of the Growth of Fatty Acid Vesicles Biophys. 87 988Google Scholar
  12. 12.
    Cistola D P, Hamilton J A, Jackson D and Small D M 1988 Ionization and Phase Behavior of Fatty Acids in Water: Application of the Gibbs Phase Rule Biochemistry 27 1881CrossRefGoogle Scholar
  13. 13.
    Apel C L, Deamer D W and Mautner M N 2002 Self-Assembled Vesicles of Monocarboxylic Acids and Alcohols: Conditions for Stability and for the Encapsulation of Biopolymers Biochim. Biophys. Acta Biomembr.  1559 1CrossRefGoogle Scholar
  14. 14.
    Markvoort A, Pfleger N, Staffhorst R, Hillbers P, Santen R ven, Killian J and Kruijff B de 2010 Electron Spin Resonance Study of the pH-Induced Transformation of Micelles to Vesicles in an Aqueous Oleic Acid/Oleate System Biophys. J. 99 1520Google Scholar
  15. 15.
    Morigaki K and Walde P 2002 Giant Vesicle Formation from Oleic Acid/Sodium Oleate on Glass Surfaces Induced by Adsorbed Hydrocarbon Molecules Langmuir 18 10509CrossRefGoogle Scholar
  16. 16.
    Dejanović B, Noethig-Laslo V, Šentjurc M and Walde P 2011 On the Surface Properties of Oleate Micelles and Oleic Acid/ Oleate Vesicles Studied by Spin Labeling Chem. Phys. Lipids  164 83CrossRefGoogle Scholar
  17. 17.
    Morrow B H, Koenig P H and Shen J K 2013 Self-Assembly and Bilayer-Micelle Transition of Fatty Acids Studied by Replica-Exchange Constant pH Molecular Dynamics Langmuir 29 14823CrossRefGoogle Scholar
  18. 18.
    Bachmann P A, Luisi P L and Lang J 1992 Physical Catalysis Driven by a Bond-Forming Thiol-Ene Reaction Nature 357 57CrossRefGoogle Scholar
  19. 19.
    Bachmann P A, Walde P, Luisi P L and Lang J 1990 Self-Replicating Reverse Micelles and Chemical Autopoiesis J. Am. Chem. Soc. 112 8200CrossRefGoogle Scholar
  20. 20.
    Kanicky J R and Shah D O 2003 Effect of Premicellar Aggregation on the pKa of Fatty Acid Soap Solutions Langmuir 19 2034CrossRefGoogle Scholar
  21. 21.
    Suga K, Kondo D, Otsuka Y, Okamoto Y and Umakoshi H 2016 Characterization of Aqueous Oleic Acid/Oleate Dispersions by Fluorescent Probes and Raman Spectroscopy Langmuir 32 7606CrossRefGoogle Scholar
  22. 22.
    Kamp F, Zakim D, Zhang F, Noy N and Hamilton J A 1995 Fatty Acid Flip-Flop in Phospholipid Bilayers is Extremely Fast Biochemistry 34 11928CrossRefGoogle Scholar
  23. 23.
    Monnard P A and Deamer D W 2003 Preparation of Vesicles from Nonphospholipid Amphiphiles Methods Enzymol. 372 133CrossRefGoogle Scholar
  24. 24.
    Kuchlyan J, Kundu N and Sarkar N 2016 Ionic Liquids in Microemulsions: Formulation and Characterization Curr. Opin. Colloid Interface Sci. 25 27CrossRefGoogle Scholar
  25. 25.
    Pandey S, Trivedi S, Mishra S K, Pandey P S and Pandey S 2015 Effect of a Surface-Active Lonic Liquid on Calixarenes In Ionic Liquid-Based Surfactant Science: Formulation, Characterization and Applications Bidyut K Paul and Satya P Moulik (Eds.) (John Wiley & Sons.) Ch. 9 p. 193Google Scholar
  26. 26.
    Galgano P D and El Seoud O A 2011 Surface Active Ionic Liquids: Study of the Micellar Properties of 1-(1-Alkyl)-3-methylimidazolium Chlorides and Comparison With Structurally Related Surfactants J. Colloid Interface Sci. 361 186CrossRefGoogle Scholar
  27. 27.
    Gu Y, Shi L, Cheng X, Lu F and Zheng L 2013 Aggregation Behavior of 1-Dodecyl-3-methylimidazolium Bromide in Aqueous Solution: Effect of Ionic Liquids with Aromatic Anions Langmuir 29 6213CrossRefGoogle Scholar
  28. 28.
    Wang H, Wang J, Zhang S B and Xuan X P 2008 Structural Effects of Anions and Cations on the Aggregation Behavior of Ionic Liquids in Aqueous Solutions J. Phys. Chem. B 112 16682CrossRefGoogle Scholar
  29. 29.
    Brown P, Butts C P, Eastoe J, Fermin D, Grillo I, Lee H, Parker D, Plana D and Richardson R M 2012 Anionic Surfactant Ionic Liquids with 1-Butyl-3-methyl-imidazolium Cations: Characterization and Application Langmuir 28 2502CrossRefGoogle Scholar
  30. 30.
    Yuan J, Bai X, Zhao M and Zheng L 2010 C\(_{12}\)mimBr Ionic Liquid/SDS Vesicle Formation and Use As Template for the Synthesis of Hollow Silica Spheres Langmuir 26 11726CrossRefGoogle Scholar
  31. 31.
    Mandal S, Kuchlyan J, Ghosh S, Banerjee C, Kundu N, Banik D and Sarkar N 2014 Vesicles Formed in Aqueous Mixtures of Cholesterol and Imidazolium Surface Active Ionic Liquid: A Comparison with Common Cationic Surfactant by Water Dynamics J. Phys. Chem. B 118 5913CrossRefGoogle Scholar
  32. 32.
    Zettl H, Portnoy Y, Gottlieb M and Khaisch G 2005 Investigation of Micelle Formation by Fluorescence Correlation Spectroscopy J. Phys. Chem. B 109 13397CrossRefGoogle Scholar
  33. 33.
    Orte A, Ruedas-Rama M J, Paredes J M, Crovetto L and Alvarez-Pez J M 2011 Dynamics of Water-in-Oil Nanoemulsions Revealed by Fluorescence Lifetime Correlation Spectroscopy Langmuir 27 12792CrossRefGoogle Scholar
  34. 34.
    Korlach J, Schwille P, Webb W W and Feigenson G W 1999 Characterization of Lipid Bilayer Phases by Confocal Microscopy and Fluorescence Correlation Spectroscopy Proc. Natl. Acad. Sci. U.S.A. 96 8461CrossRefGoogle Scholar
  35. 35.
    Benda A, Benes M, Merecek V, Lhotsky A, Hermens W Th and Hof M 2003 How To Determine Diffusion Coefficients in Planar Phospholipid Systems by Confocal Fluorescence Correlation Spectroscopy Langmuir 19 4120CrossRefGoogle Scholar
  36. 36.
    Humpolickova J, Gielen E, Benda A, Fagulova J, Vercammen J, Vandeven M, Hof M, Ameloot M and Engelborghs Y 2006 Probing Diffusion Laws within Cellular Membranes by Z-Scan Fluorescence Correlation Spectroscopy Biophys. J. 91 L23Google Scholar
  37. 37.
    Kirkeminde A W, Torres T, Ito T and Higgins D A 2011 Multiple Diffusion Pathways in Pluronic F127 Mesophases Revealed by Single Molecule Tracking and Fluorescence Correlation Spectroscopy J. Phys. Chem. B 115 12736CrossRefGoogle Scholar
  38. 38.
    Patra S and Samanta A 2012 Microheterogeneity of Some Imidazolium Ionic Liquids As Revealed by Fluorescence Correlation Spectroscopy and Lifetime Studies J. Phys. Chem. B 116 12275CrossRefGoogle Scholar
  39. 39.
    Wang D, Yuan Y, Mardiyati Y, Bubeck C and Koynov K 2013 From Single Chains to Aggregates, How Conjugated Polymers Behave in Dilute Solutions Macromolecules 46 6217CrossRefGoogle Scholar
  40. 40.
    Wu D and Schanze K S 2014 Protein Induced Aggregation of Conjugated Polyelectrolytes Probed with Fluorescence Correlation Spectroscopy: Application to Protein Identification ACS Appl. Mater. Interfaces 6 7643CrossRefGoogle Scholar
  41. 41.
    Sahoo B, Balaji J, Nag S, Kaushalya K and Maiti S 2008 Protein Aggregation Probed by Two-Photon Fluorescence Correlation Spectroscopy of Native Tryptophan J. Chem. Phys129 075103CrossRefGoogle Scholar
  42. 42.
    Pal N, Verma S D, Singh M K and Sen S 2011 Fluorescence Correlation Spectroscopy: an Efficient Tool for Measuring Size, Size-Distribution and Polydispersity of Microemulsion Droplets in Solution Anal. Chem83 7736CrossRefGoogle Scholar
  43. 43.
    Müller C B, Loman A, Richtering W and Enderlein J 2008 Dual-Focus Fluorescence Correlation Spectroscopy of Colloidal Solutions: Influence of Particle Size J. Phys. Chem. B 112 8236CrossRefGoogle Scholar
  44. 44.
    Ishii K and Tahara T 2013 Two-Dimensional Fluorescence Lifetime Correlation Spectroscopy. 2. Application J. Phys. Chem. B 117 11432Google Scholar
  45. 45.
    Schubert F, Zettl H, Hafner W, Krauss G and Krausch G 2003 Comparative Thermodynamic Analysis of DNA–Protein Interactions Using Surface Plasmon Resonance and Fluorescence Correlation Spectroscopy Biochemistry 42 10288Google Scholar
  46. 46.
    Burnett G R, Rees G D, Styetler D C and Robinson B H 2004 Fluorescence Correlation Spectroscopy of Water-in-Oil Microemulsions: an Application in Specific Characterization of Droplets Containing Biomolecules Colloids Surf. A 250 171Google Scholar
  47. 47.
    Mojumdar S S, Chowdhury R, Chattoraj S and Bhattacharyya K 2012 Role of Ionic Liquid on the Conformational Dynamics in the Native, Molten Globule, and Unfolded States of Cytochrome C: A Fluorescence Correlation Spectroscopy Study J. Phys. Chem. B 116 12189CrossRefGoogle Scholar
  48. 48.
    Dey S, Mandal U, Mojumdar S S, Mandal A K and Bhattacharyya K 2010 Diffusion of Organic Dyes in Immobilized and Free Catanionic Vesicles J. Phys. Chem. B 114 15506CrossRefGoogle Scholar
  49. 49.
    Israelachvili J N, Mitchell D J and Ninham B W 1976 Theory of Self-Assembly of Hydrocarbon Amphiphiles into Micelles and Bilayers J. Chem. Soc., Faraday Trans. 2  72 1525CrossRefGoogle Scholar
  50. 50.
    Ferrer-Tasies L, Moreno-Calvo E, Cano-Sarabia M, Aguilella-Arzo M, Angelova A, Lesieur S, Ricart S, Faraudo J, Ventosa N and Veciana J 2013 Quatsomes: Vesicles Formed by Self-Assembly of Sterols and Quaternary Ammonium Surfactants Langmuir 29 6519CrossRefGoogle Scholar
  51. 51.
    Karatekin E and Rothman J E 2012 Fusion of Single Proteoliposomes with Planar, Cushioned Bilayers in Microfluidic Flow Cells Nat. Protoc. 7 903PubMedGoogle Scholar
  52. 52.
    Terasawa E, Nishimura K, Suzuki H, Matsuura T and Yomo T 2012 Coupling of the Fusion and Budding of Giant Phospholipid Vesicles Containing Macromolecules Proc. Natl. Acad. Sci. U.S.A. 109 5942CrossRefGoogle Scholar
  53. 53.
    Ohki S and Arnold K 2000 A Mechanism for Ion-Induced Lipid Vesicle Fusion Colloids Surf. B 18 83Google Scholar
  54. 54.
    Kantor H L and Prestegard J H 1978 Fusion of Phosphatidylcholine Bilayer Vesicles: Role of Free Fatty Acid Biochemistry  17 3592CrossRefGoogle Scholar
  55. 55.
    Henderson I M and Paxton W F 2014 Salt, Shake, Fuse–Giant Hybrid Polymer/Lipid Vesicles through Mechanically Activated Fusion Angew. Chem. Int. Ed53 3372Google Scholar
  56. 56.
    Carmona-Ribeiro A M and Chaimovich H 1986 Salt-Induced Aggregation and Fusion of Dioctadecyldimethylammonium Chloride and Sodium Dihexadecylphosphate Vesicles Biophys. J. 50 621Google Scholar
  57. 57.
    Roy A, Banerjee P, Dutta R, Kundu S and Sarkar N 2016 Probing the Interaction between a DNA Nucleotide (Adenosine-\(5^\prime \)-Monophosphate Disodium) and Surface Active Ionic Liquids by Rotational Relaxation Measurement and Fluorescence Correlation Spectroscopy Langmuir  32 10946Google Scholar
  58. 58.
    Berezin M Y and Achilefu S 2010 Fluorescence Lifetime Measurements and Biological Imaging Chem. Rev110 2641CrossRefGoogle Scholar
  59. 59.
    Lin H J, Herman P and Lakowicz J R 2003 Fluorescence Lifetime-Resolved pH Imaging of Living Cells Cytometry Part A 52 77CrossRefGoogle Scholar
  60. 60.
    Setiawan I and Blanchard G J 2014 Ethanol-Induced Perturbations to Planar Lipid Bilayer Structures J. Phys. Chem. B 118 537CrossRefGoogle Scholar
  61. 61.
    Setiawan I and Blanchard G J 2014 Structural Disruption of Phospholipid Bilayers over a Range of Length Scales by n-Butanol J. Phys. Chem. B 118 3085CrossRefGoogle Scholar
  62. 62.
    Suga K, Yokoi T, Kondo D, Hayashi K, Morita S, Okamoto Y, Shimanouchi T and Umakoshi H 2014 Systematical Characterization of Phase Behaviors and Membrane Properties of Fatty Acid/Didecyldimethylammonium Bromide Vesicles Langmuir 30 12721CrossRefGoogle Scholar
  63. 63.
    Kundu N, Banerjee P, Kundu S, Dutta R and Sarkar N 2017 Sodium Chloride Triggered the Fusion of Vesicle Composed of Fatty Acid Modified Protic Ionic Liquid: A New Insight into the Membrane Fusion Monitored through Fluorescence Lifetime Imaging Microscopy J. Phys. Chem. B 121 24CrossRefGoogle Scholar
  64. 64.
    Sasmal D K, Mandal A K, Mondal T and Bhattacharyya K 2011 Diffusion of Organic Dyes in Ionic Liquid and Giant Micron Sized Ionic Liquid Mixed Micelle: Fluorescence Correlation Spectroscopy J. Phys. Chem. B  115 7781CrossRefGoogle Scholar
  65. 65.
    Ghosh S, Adhikary A, Sen Mojumdar S and Bhattacharyya K 2010 A Fluorescence Correlation Spectroscopy Study of the Diffusion of an Organic Dye in the Gel Phase and Fluid Phase of a Single Lipid Vesicle J. Phys. Chem. B 114 5736CrossRefGoogle Scholar
  66. 66.
    Roy A, Dutta R, Banerjee P, Kundu S and Sarkar N 2016 5-Methyl Salicylic Acid-Induced Thermo Responsive Reversible Transition in Surface Active Ionic Liquid Assemblies: A Spectroscopic Approach Langmuir 32 7127CrossRefGoogle Scholar
  67. 67.
    Zakir F, Vaidya B, Goyal A K, Malik B and Vyas S P 2010 Development and Characterization of Oleic Acid Vesicles for the Topical Delivery of Fluconazole Drug Deliv. 17 238CrossRefGoogle Scholar
  68. 68.
    Verma S, Bharadwaj A, Vij M, Bajpai P, Goutam N and Kumar L 2013 Oleic Acid Vesicles: A New Approach for Topical Delivery of Antifungal Agent Artif. Cells Nanomed. Biotechnol. 42 95CrossRefGoogle Scholar

Copyright information

© Indian Academy of Sciences 2018

Authors and Affiliations

  1. 1.Department of ChemistryIndian Institute of TechnologyKharagpurIndia
  2. 2.Centre for Innovations in MedicineArizona State UniversityTempeUnited States

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