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研究生:吳清茂
研究生(外文):Ching-Mao Wu
論文名稱:DNA-脂質錯合體自組裝結構之研究
論文名稱(外文):Self-Assembled Architecture of DNA-Lipid Complexes
指導教授:陳信龍陳信龍引用關係
指導教授(外文):Hsin-Lung Chen
學位類別:博士
校院名稱:國立清華大學
系所名稱:化學工程學系
學門:工程學門
學類:化學工程學類
論文種類:學術論文
論文出版年:2004
畢業學年度:92
語文別:英文
論文頁數:121
中文關鍵詞:基因治療DNA/陽離子微脂粒錯合體DC-CholDOPC凝結脂質
外文關鍵詞:gene therapyDNA/cationic liposome complexesDC-CholDOPCcondensationlipids
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Polyanionic DNA can bind electrostatically with cationic liposomes (CLs) to form the complex exhibiting rich self-assembled structures at various length scales. This class of bioassembly has been considered as a nonviral gene delivery system for gene therapy or as a template for nanostructure construction. Understanding the self-assembly of DNA/CL complexes is crucial both for building the detailed nucleic acid delivery mechanism and also for application of this class of materials as nanostructural templates. This dissertation investigates the self-assemblies of the bioassemblies of DNA with (1) a cationic lipid, cholesteryl 3β-N-((dimethylamino)et-
hyl)carbamate (DC-Chol), (2) a zwitterionic lipid, 1,2-di(cis-9-octadecenoyl)-sn-glyc-
ero-3-phosphocholine (DOPC), and (3) with both DC-Chol and DOPC.
The self-assembled structure of DNA-DC-Chol complexes in excess water was first reported. Neat DC-Chol self-assembled into cylindrical micelles in aqueous media. These micelles aggregated and fused into multilamellar condensates or vesicles upon complexation with DNA, and DNA chains confined between the lipid bilayers formed closely packed arrays irrespective of overall lipid-to-base pair molar ratio. The complexation was found to be a highly cooperative process, where the complexes with nearly 1:1 stoichiometry were formed even when DNA was in excess of DC-Chol in terms of the overall ionic charge. As DC-Chol became in excess, the unbound lipid did not fully macrophase separate from the stoichiometric complex but segregated to form domains coexisting with the bound lipid domains in the lamellae. The presence of these unbound lipid domains reduced the persistence length of the membrane and consequently induced topological transformation of the multilamellar phase from platelike lamellae to circular lamellae observed by TEM at higher DC-Chol composition.
The self-assembly of DNA-DC-Chol complexes in the bulk state (i.e., solid state) has been investigated by SAXS. Two multilamellar phases, LI and LII, characterized by distinct states of lipid stacking and DNA conformation were observed. LII phase, formed when the lipid was in excess of DNA in terms of overall ionic charge, composed of B-DNA confined between the bilayers with the lipid tails aligning normal to the lamellar interface. When DNA are in excess, LI phase, in which the A-DNA bound with the titled lipid chains adopts A-form conformation, was favored as it offered more economical binding between these two components.
The aggregation of a zwitterionic liposome composed of DOPC induced by DNA without the presence of multivalent salt has been revealed. Our results demonstrate that only a small fraction (< 10%) of DNA can bind electrostatically with a portion of the liposomes. Such a low degree of binding however induces significant aggregation of these oligolamellar liposomes to yield large multilamellar particles in which the number of hydrophilic/hydrophobic layers along the lamellar stacking direction becomes sufficiently large to yield multiple diffraction peaks in the small angle X-ray scattering (SAXS) profile. Addition of monovalent salt such as NaCl tends to disrupt the multilamellar structure.
Finally, a multilamellar DNA-DC-Chol-DOPC complex was adopted to study the effect of divalent metal ions on the packing density of DNA condensed on the surfaces of the rigid DC-Chol/DOPC membrane. This study is distinguished from the previous one demonstrating that divalent metal ions can induce further condensation of DNA lying on the surfaces of fluid cationic membranes in that the membrane system adopted here is a rigid one. Our results demonstrate that the divalent cations, Ca2+ and Ni2+, only exerted an electrostatic screening effect between DNA but did not induce collapse transition of the DNA into a condensed state.
Polyanionic DNA can bind electrostatically with cationic liposomes (CLs) to form the complex exhibiting rich self-assembled structures at various length scales. This class of bioassembly has been considered as a nonviral gene delivery system for gene therapy or as a template for nanostructure construction. Understanding the self-assembly of DNA/CL complexes is crucial both for building the detailed nucleic acid delivery mechanism and also for application of this class of materials as nanostructural templates. This dissertation investigates the self-assemblies of the bioassemblies of DNA with (1) a cationic lipid, cholesteryl 3β-N-((dimethylamino)et-
hyl)carbamate (DC-Chol), (2) a zwitterionic lipid, 1,2-di(cis-9-octadecenoyl)-sn-glyc-
ero-3-phosphocholine (DOPC), and (3) with both DC-Chol and DOPC.
The self-assembled structure of DNA-DC-Chol complexes in excess water was first reported. Neat DC-Chol self-assembled into cylindrical micelles in aqueous media. These micelles aggregated and fused into multilamellar condensates or vesicles upon complexation with DNA, and DNA chains confined between the lipid bilayers formed closely packed arrays irrespective of overall lipid-to-base pair molar ratio. The complexation was found to be a highly cooperative process, where the complexes with nearly 1:1 stoichiometry were formed even when DNA was in excess of DC-Chol in terms of the overall ionic charge. As DC-Chol became in excess, the unbound lipid did not fully macrophase separate from the stoichiometric complex but segregated to form domains coexisting with the bound lipid domains in the lamellae. The presence of these unbound lipid domains reduced the persistence length of the membrane and consequently induced topological transformation of the multilamellar phase from platelike lamellae to circular lamellae observed by TEM at higher DC-Chol composition.
The self-assembly of DNA-DC-Chol complexes in the bulk state (i.e., solid state) has been investigated by SAXS. Two multilamellar phases, LI and LII, characterized by distinct states of lipid stacking and DNA conformation were observed. LII phase, formed when the lipid was in excess of DNA in terms of overall ionic charge, composed of B-DNA confined between the bilayers with the lipid tails aligning normal to the lamellar interface. When DNA are in excess, LI phase, in which the A-DNA bound with the titled lipid chains adopts A-form conformation, was favored as it offered more economical binding between these two components.
The aggregation of a zwitterionic liposome composed of DOPC induced by DNA without the presence of multivalent salt has been revealed. Our results demonstrate that only a small fraction (< 10%) of DNA can bind electrostatically with a portion of the liposomes. Such a low degree of binding however induces significant aggregation of these oligolamellar liposomes to yield large multilamellar particles in which the number of hydrophilic/hydrophobic layers along the lamellar stacking direction becomes sufficiently large to yield multiple diffraction peaks in the small angle X-ray scattering (SAXS) profile. Addition of monovalent salt such as NaCl tends to disrupt the multilamellar structure.
Finally, a multilamellar DNA-DC-Chol-DOPC complex was adopted to study the effect of divalent metal ions on the packing density of DNA condensed on the surfaces of the rigid DC-Chol/DOPC membrane. This study is distinguished from the previous one demonstrating that divalent metal ions can induce further condensation of DNA lying on the surfaces of fluid cationic membranes in that the membrane system adopted here is a rigid one. Our results demonstrate that the divalent cations, Ca2+ and Ni2+, only exerted an electrostatic screening effect between DNA but did not induce collapse transition of the DNA into a condensed state.
TABLE OF CONTENT

ACKNOWLEDGEMENTS............................................................................................I
ABSTRACT.................................................................................................................III
TABLE OF CONTENT……………………………………………………………….V
LIST OF TABLES.....................................................................................................VIII
LIST OF FIGURES…………………………………………………………..………IX

CHAPTER

1. INTRODUCTION AND LITERATURE SURVEY....................................1

1.1 Background............................................................................................1
1.2 Literature Survey………………………………………………………4

1.2.1 A Brief Overview of Cationic Liposomes……………………….4

A. Chemical Structure and Polymorphism of Lipids…………..6
B. Mechanism of Liposome Formation………………………..6
C. Gel-Liquid Crystalline Phase Transition of Lipid Bilayers…9

1.2.2 Progress in the Finding of Self-Assembled Structures of
DNA-Cationic Liposome Complex……………………………10

A. Self-Assembled Structures of DNA-Cationic Liposome
Complexes………………………………………………10
B. DNA-CL Complex Formation and Thermodynamic
Driving Force……………………………………………...15
C. Condensation of DNA onto Lipid Bilayers and Effect of
Divalent Cations………………………………………19
D. DNA-Zwitterionic Lipid-divalent Cation (DNA-ZL-Me2+)
Complexes...........................................................................24

1.3 Motivations of Study and Overview of the Dissertation....................25
1.4 References............................................................................................30


2. SELF-ASSEMBLED STRUCTURE OF THE BINARY COMPLEX OF DNA WITH CATIONIC LIPID…………………………………………..33

2.1 Introduction.........................................................................................33
2.2 Experimental Section………………………………………………...35

2.2.1 Materials and Complex Preparations………………………...35
2.2.2 Ultraviolet-Visible (UV-Vis) Spectroscopy Experiment……. 35
2.2.3 Small-Angle X-ray Scattering (SAXS) Measurements……... 36
2.2.4 Transmission Electron Microscopy (TEM) Experiment……. 36

2.3 Results and Discussion……………………………………………….37
2.4 Conclusions…………………………………………………………..51
2.5 References and Notes………………………………………………...52

3. A TWO-STATE MODEL FOR THE MULTILAMELLAR STRUCTURE OF DNA/CATIONIC LIPID COMPLEX IN THE BULK
…………………………………………………………………………… ...55

3.1 Introduction…………………………………………………………..55
3.2 Experimental Section……………………………………………….56

3.2.1 Materials and Complex Preparations………………………..56
3.2.2 X-Ray Measurements………………………………………...56
3.3 Results and Discussion…………………………………………57
3.4 Conclusions………………………………………………………66
3.5 References and Notes………………………………………………...68

4. DNA-INDUCED AGGREGATION OF ZWITTERIONIC OLIGOLAMELLAR LIPOSOME ………………………………………70

4.1 Introduction…………………………………………………………70
4.2 Experimental Section……………………………………………72

4.2.1 Materials and Methods……………………………………72
4.2.2 SAXS Measurements………………………………………..72
4.2.3 TEM Observations.............................................................73
4.2.4 Ultraviolet-Visible (UV-Vis) Spectroscopy Experiment..........74

4.3 Results and Discussion…………………………………………74
4.4 Conclusions………………………………………………………84
4.5 References………………………………………………………85

5. EFFECT OF DIVALENT METAL IONS ON DNA CONDENSED ON THE SURFACES OF RIGID CATIONIC MEMBRANES………………87

5.1 Introduction……………………………………………………87
5.2 Experimental Section……………………………………………….88

5.2.1 Materials and Sample Preparations........................................88
5.2.2 TEM Experiments.................................................................89
5.2.3 SAXS Measurements…………………………………90
5.2.4 Differential Scanning Calorimeter (DSC)……………90

5.3 Results and Discussion…………………………………………91
5.4 Conclusions……………………………………………………104
5.5 References………………………………………………………106


















LIST of TABLES

Tables

1.1. The most key findings of self-assembled structures of DNA-CL complexes...12

5.1. DSC characterization of the phase transition exhibited by DOPC and DC-Chol
/DOPC mixtures……………………………………………………………….100





























LIST OF FIGURES

Figures

1.1 Simplified schematic presentation of the transfection…………………………3
1.2 The schematic presentations of liposomes……………………………………….5
1.3 Schematic representations of lipid-water phase: (a) lamellar gel; (b) lamellar liquid crystalline; (c) hexagonal type II; (d) hexagonal type I. Various dimensions that can be measured by X-ray diffraction are indicated…………………………7
1.4 A schematic view of the geometric considerations for forming micelles and bilayers…………………………………………………………………………...8
1.5 (A) Differential scanning calorimetry profiles of three phospholipids. (B) Schematic showing the molecular organization of phosphatidylcholine and phosphatidylethanolamine as a function of temperature………………………11
1.6 Schematic of two distinct pathways from the lamellar phase to the columnar inverted hexagonal phase of CL-DNA complexes……………..14
1.7 Cationic lipid-DNA complexes embedded in vitreous ice and imaged by cryo-el- ectron microscopy………………………………………………………………16
1.8 Two typical images of the condensed DNA molecules on DPDAP in 20 mM NaCl and the corresponding Fourier transforms………………………………..17
1.9a An abundance of DNA-coated unilamellar vesicles are evident in samples with higher DNA/lipid charge ratio = 0.9. Multilamellar complexes are present in low amounts. These complexes often possess unclosed outer bilayers. The white arrows indicate the edges of unclosed bilayers. The dark spots near the edges in (B) are believed to be caused by DNA accumulating or coiling at the edges. Black arrows indicate unilamellar vesicles on which the pattern caused by the parallel DNA helices is particularly well-visible……………………………….18
1.9b Clusters of DNA-coated unilamellar vesicles at DNA/lipid charge ratio = 0.9. As in Fig. 1.9a, the black arrows indicate locations where the pattern caused by adsorbed DNA is best visible. Flattening of the bilayers at the contact regions of adjacent vesicles is evident……………………………………………………..18
1.10 Proposed mechanism for the reorganization of lipid bilayers in the presence of DNA…………………………………………………………………………….20
1.11 (a) Synchrotron XRD measurements of the powder isoelectric [ρ= (weight lipid)/(weight DNA) = 2.2, ΦDOPC = (weight DOPC)/(weight lipid) =mole fraction of DOPC = 0.6] CL-DNA complex samples in the presence of MgCl2. dDNA abruptly changes from 47 Å (set by ΦDOPC) at low MgCl2 concentrations (M) to 28.9 Å above M = M* = 48.2 mM. Also, the complex periodicity d increases to 70 ± 1 Å for M > M*. (b) Similar XRD measurements in the presence of CoCl2 show that Co2+ ions also cause a condensation transition of the 2D DNA arrays but at smaller M* ≈ 24 mM. The (003) peak appears for M > M* in a and b, while the (004) is visible below and above M*. This is because the (003) peak in the lipid-DNA lamellar structure factor is near a zero crossing of the form factor. For M > M*, the screening of the head groups in the presence of the trapped counterions leads to a decrease in the area per charged head group. To match the change in the area per head, the area per tail decreases through chain stretching, which leads to a different position for the zero-crossing of the form factor. (c) Variation of the dDNA with the concentrations of four different divalent salts…………………………………………………………………….22
1.12 Schematic illustration of the force reversal between DNA chains adsorbed on cationic membrane surfaces within the lamellar LαC phase. For divalent counterion concentrations M < M* the electrostatic forces (Fe) are repulsive. For M < M* the forces become attractive, which leads to the DNA condensation transition on a surface. In contrast, the electrostatic forces between DNA chains in bulk aqueous solution with divalent counterions are purely repulsive. During the transition, the spacing between the DNA double helices rapidly decreases to a separation of order the diameter of the condensing ions (shown as red spheres). In the condensed state (M > M*) there are ≈ 0.63 ions/base pair along the DNA……………………………………………………………………………23
1.13 Chemical structures of lipids used in the present work…………………………27
2.1 (a) Representative UV spectra of the supernatants for the samples with x = 0.75, 1.5 and 2.0. The existence of free DNA is clearly demonstrated by the DNA absorption peak near 260 nm. (b) The actual complex composition xa obtained from eq. 2.1 versus the corresponding prescribed composition. It can be seen that xa is about 2.2 irrespective of x…………………………………………………39
2.2 Lorentz-corrected SAXS profiles of neat DC-Chol as a function of weight fraction of water (Ww)…………………………………………………………..40
2.3 TEM micrograph of neat DC-Chol showing the formation of worm-like cylindrical micelles with the diameter of ca. 5.4 nm……………………………42
2.4 Representative Lorentz-corrected SAXS profiles of DNA/DC-Chol complexes in excess water. For x = 10.0 the multilamellar peaks in the corresponding SAXS profile appear to superpose on a broad halo (represented by the legend of filled circle) due to the presence of unbound DC-Chol micelles……………………..43
2.5 A series of TEM micrographs showing the multilamellar phases of DNA/DC-Chol complexes: (a) x = 10.0; (b) x = 3.6; (c) x = 2.4; (d) x = 0.5. In (a) the arrow marks the presence of unbound DC-Chol micelles…………………..45
2.6 Enlarged plots of the SAXS profiles showing the presence of a DNA-DNA correlation peak at ca. 2.5 nm-1 (marked by the arrows) for DNA/DC-Chol complexes………………………………………………………………………46
2.7 Relative electron density profiles of DNA/DC-Chol complexes in excess water. For x = 10 the corresponding �歋(z) profile was obtained by subtracting the broad halo associated with unbound DC-Chol from the overall scattering profile……48
2.8 Schematic model showing the coexistence of closely packed DNA arrays and water domains in the hydrophilic layer for the complexes at x > 2…………….50
3.1 X-ray scattering profiles of DNA/DC-Chol complexes in the bulk state: (a) Lorentz-corrected SAXS profiles. The multilamellar phase found below the stoichiometric composition is denoted by LI, while that observed at x > 2 is denoted by LII. The scattering pattern of the complex with x = 3.6 in excess water is also displayed for comparison; (b) wide-angle profiles; (c) enlarged plots of the SAXS profiles showing the presence of a DNA-DNA correlation peak at 2.61 nm-1 (marked by qDNA) at x > 2……………………………………58
3.2 The relative electron density profiles of DNA/DC-Chol complexes in the bulk state……………………………………………………………………………..62
3.3 Schematic illustrations of the packing modes of DC-Chol and DNA packing in (a) LI and (b) LII phases. The DNA conformations are B-form and A-form in LII and LI phases, respectively……………………………………………………..64
4.1 Lorentz-corrected SAXS profile of neat DOPC liposomes. The scattering pattern is characterized by a broad diffuse halo, indicating that the liposomes do not exhibit an ordered multilamellar structure……………………………………..75
4.2 The representative TEM micrograph of neat DOPC liposomes. Oligolamellar vesicles (consisting of 3 ~ 8 hydrophilic/hydrophobic layers per vesicle) with the dark and gray striations corresponding to the hydrophilic and hydrophobic layers, respectively are predominantly observed……………………………………….76
4.3 Photographs showing the appearances of neat DOPC (left) and DNA/DOPC (�� = 2.0) suspensions. Precipitate of DNA/DOPC (indicated by the arrow) is clearly observed at the bottom of the container, indicating aggregation of the oligolamellar liposomes into large particles upon binding with DNA…………77
4.4 Lorentz-corrected SAXS profiles showing two diffraction peaks for the DNA/DOPC precipitates in the samples with various overall lipid-to-base pair molar ratios. Also shown here is the SAXS profile of multilamellar DOPC liposomes prepared without imposing sonication to the liposome suspension. It can be seen that the SAXS patterns of the DNA/DOPC precipitates and of neat DOPC liposomes are essentially the same in terms of the positions and relative intensities of the scattering peaks……………………………………………….79
4.5 A representative TEM micrograph showing the morphology of the DNA/DOPC precipitate particles. It can be seen that the particles are simply formed by the aggregation of a number of the oligolamellar DOPC liposomes, while these liposomes did not fuse and reorganize further to form the compact multilamellar particles found in the DNA/CL complexes……………………………………..82
4.6 SAXS profiles of DNA/DOPC with �� = 2.0 dispersed in NaCl aqueous solutions with various NaCl concentrations………………………………………………83
5.1 TEM micrographs of isoelectric DNA/DC-Chol/DOPC complexes with (a) n=0.25; (b) n=1…………………………………………………………………92
5.2 (a) SAXS profiles of isoelectric DNA/DC-Chol/DOPC complexes with distinct n in excess water. (b) Variation of d and dDNA as a function of n…………………93
5.3 Comparative SAXS profiles of isoelectric DNA/DC-Chol/DOPC complex with n=3 in excess water and pure DOPC with weight fraction of water (Ww = 0.7)..95
5.4 (a) SAXS profiles of isoelectric DNA/DC-Chol/DOPC complexes with n = 2.5 dispensed in CaCl2 aqueous solutions with different CaCl2 concentrations. (b) Variation of d and dDNA as a function of CaCl2 concentrations…………………96
5.5 (a) SAXS profiles of isoelectric DNA/DC-Chol/DOPC complexes with n = 2.5 dispensed in NiCl2 aqueous solutions with different NiCl2 concentrations. (b) Variation of d and dDNA as a function of NiCl2 concentrations…………………98
5.6 Representative DSC thermograms of pure DOPC and DC-Chol/DOPC mixture with various ratios………………………………………………………………99
5.7 Schematic possible model illustrating (a) inclusion of DC-Chol into DOPC bilayers results in the formation of liquid-ordered domains composed of DC-Chol/DOPC lipid mixtures (denoted as lo) and liquid-disordered domains composed only of DOPC (denoted as ld). DNA in the complex selectively binds to lo domains because of the electrostatic attractions and long-range repulsions exist between DNA molecules. When divalent metal ions (indicated by small red spheres) are added into DNA-CL complex suspensions, they get adsorbed onto the surfaces of bilayers and situate around DNA rods to mediate the interhelical repulsions. (b) At the critical ionic concentration (C*), charge reversal between DNA molecules occurs and hence they approach each other (as depicted by arrow on DNA), leading to the reduction of interhelical spacing and release of DOPC lipids between lo domains by lateral diffusion. The lo domains behave like rigid barrier walls and reduce the lateral diffusive rates of DOPC lipids so that they cannot immediately diffuse out at corresponding ionic concentrations…102
Chapter 1
(1) Huang, L.; Hung, M. C.; Wagner, E. Nonviral Vectors for Gene Therapy. Academic Press: New York, 1999.
(2) Lasic, D. D.; Templeton, N. S. Adv. Drug Delivery Rev. 1996, 20, 221.
(3) Miller A. D. Angew. Chem. Int. Ed. 1998, 37, 1768.
(4) Chesnoy, S.; Huang, L. Annu. Rev. Biophs. Biomol. Struct. 2000, 29, 27.
(5) Amos, H. Biochem. Biophys. Res. Comm. 1961, 5, 1.
(6) Dimitriadis, D. Nucleic Acid Res. 1979, 6, 2697.
(7) Fraley, P.; Subramani, S.; Berg, P.; Papahadjopoulos, D. J. Biol. Chem. 1980, 255, 10431.
(8) Felgner, P. L.; Gadek, T. R.; Holm, M.; Roman, R.; Chan, H. W.; Wenz, M., Northrop, J. P.; Ringold, G. M.; Danielsen, M. Proc. Natl. Acad. Sci. U.S.A. 1987, 84, 7413.
(9) Fraley, P.; Papahadjopoulos, D. Curr. Top. Microbial. Immunol. 1982, 96, 171.
(10) Hoffmam, R. M.; Margolis, L. B.; Bergelson, L. D. FEBS Lett. 1978, 93, 365.
(11) Budker, V. G..; Godvikov, A. A.; Naumova, L. P.; Slepneva, I. A. Nucleic Acid
Res. 1980, 8, 2499.
(12) Behr, J. P. Tetrahedron Lett. 1986, 27, 5861.
(13) Xu, Y., Szoka, F. C. Biochemistry 1996, 35, 5616.
(14) Rädler, J. O.; Koltover, I.; Salditt, T.; Safinya, C. R. Science 1997, 275, 810.
(15) Koltover, I.; Salditt, T.; Rädler, J. O.; Safinya, C. R. Science 1998, 281, 78.
(16) Zhou, S.; Chu, B. Adv. Mater. 2000, 12, 545.
(17) Antonietti, M.; Burger, C.; Effing, J. Adv. Mater. 1995, 7, 751.
(18) Ober, C. K.; Wegner, G. Adv. Mater. 1997, 8, 17.
(19) Liang, H.; Angelini, T. E.; Ho, J.; Braun, P. V.; Wong, G. C. L. J. Am. Chem.
Soc. 2003, 125, 11786.
(20) Gennis, R. B. Biomembranes: Molecular Structure and Function.
Springer-Verlag Press: New York, 1989.
(21) Israelachvili, J. Innermolcular and Surface Forces. Academic Press: New York,
1985.
(22) Kreuter, J. Colloidal Drug Delivery Systems. Marcel Dekker Press: New York,
1994.
(23) New, R. R. C. Liposomes A Practical Approach. Oxford University Press: New
York, 1990.
(24) Ruocco, M. J.; Shipley, G. G. Biochim. Biophys. Acta. 1982, 684, 59.
(25) Slater, J. L.; Huang, C. Biophys. J. 1987, 52, 667.
(26) Safinya, C. R. Curr. Opinion Struct. Biol. 2001, 11, 440.
(27) Felgner, P. L. Nature 1991, 349, 351.
(28) Sternberg, B.; Sorgi, F. L.; huang, L. FEBS Lett. 1994, 356, 361.
(29) Gustafsson, J.; Arvidson, G..; Karlsson, G.; Almgren, M. Biochim. Biophys. Acta.
1995, 1235, 305.
(30) Lasic, D. D.; Strey, H.; Stuart, M. C. A.; Podgornik, R.; Frederik, P. M. J. Am.
Chem. Soc. 1997, 119, 832.
(31) Koltover, I.; Salditt, T.; Safinya, C. R. Biophys. J. 1999, 77, 915.
(32) Rädler, J.O.; Koltover, I.; Jamieson, A.; Salditt, T.; Safinya, C. R. Langmuir
1998, 14, 4272.
(33) Subramanian, G.; Hjelm, R. P.; Deming, T. J.; Smith, G. S.; Li, Y.; Safinya, C. R.
J. Am. Chem. Soc. 2000, 122, 26.
(34) Wong, G. C. L.; Tang, J. X.; Lin, A.; Li, Y.; Janmey, P. A.; Safinya, C. R. Science
2000, 288, 2035.
(35) Battersby, B. J.; Grimm, R.; Huebner, S.; Cevc, G. Biochim. Biophys. Acta. 1998,
1235, 379.
(36) Huebner, S.; Battersby, B. J.; Grimm, R.; Cevc, G. Biophys J. 1999, 76, 3158.
(37) Kennedy, M.; Pozharski, E. V.; Rakhmanova, V. A.; MacDonald R.C. Biophys. J.
2000, 78, 1620.
(38) Wagner, K.; Harries, D.; May. S.; Kahl, V.; Rädler, J. O.; Ben-Shaul, A.
Langmuir 2000, 16, 303.
(39) Bloomfield, V. A. Biopolymers 1991, 31, 1471.
(40) Bloomfield, V. A. Curr. Opinion Struct. Biol. 1996, 6, 334.
(41) Bloomfield, V. A. Biopolymers 1997, 44, 269.
(42) Fang, Y.; Yang, J. J. Phys. Chem. B 1997, 101, 441.
(43) Fang, Y.; Yang, J. J. Phys. Chem. B 1997, 101, 3453.
(44) Fang, Y.; Hoh, J. H. J. Am. Chem. Soc. 1998, 120, 8903.
(45) Koltover, I.; Wagner, K.; Safinya, C. R. Proc. Natl. Acad. Sci. U.S.A. 2000, 97,
14046.
(46) Lin, A. J.; Slack, N. L.; Ahmad, A.; George, C. X.; Samuel, C. E.; Safinya, C. R.
Biophys. J. 2003, 84, 3307.
(47) Pott, T.; Roux, D. FEBS Lett. 2002, 511, 150.
(48) Monnard, P.; Berclaz, N.; Conde-Frieboes, K.; Oberholzer, T. Langmuir
1999, 15, 7504.
(49) Tarahovsky, Y. S.; Khusainova, R. S.; Gorelov, A. V.; Nicolaeva, T. I.;
Deev, A. A.; Dawson, A. K.; Ivanitsky, G. R. FEBS Lett. 1996, 390, 133.
(50) Kharakoz, D. P.; Khusainova, R. S.; Gorelov, A. V.; Dawson, K. A.
FEBS Lett. 1999, 446, 27.
(51) Hayes, M. E.; Gorelov, A. V.; Dawson, K. A. Progr. Colloid. Polym. Sci.
2001, 118, 243.
(52) Francescangeli, O.; Stanic, V.; Gobbi, L.; Bruni, P.; Iacussi, M.; Tosi, G.
Phys. Rev. E 2003, 67, 011904.
(53) McManus, J. J.; Rädler, J. O.; Dawson, K. A. J. Phys. Chem. B 2003, 107, 9869.
(54) O’Hern, C. S.; Lubensky, T. C. Phys. Rev. Lett. 1998, 80, 4345.
(55) Schmutz, M.; Durand, D.; Debin, A.; Palvadeau, Y.; Etienne, A.; Thierry, A. R.
Proc. Natl. Acad. Sci. U.S.A. 1999, 96, 12293.

Chapter 2
(1) Zhou, S.; Chu, B. Adv. Mater. 2000, 12, 545.
(2) Antonietti, M.; Burger, C.; Effing, J. Adv. Mater. 1995, 7, 751.
(3) Ober, C. K.; Wegner, G. Adv. Mater. 1997, 8, 17.
(4) Rädler, J. O.; Koltover, I.; Salditt, T.; Safinya, C. R. Science 1997, 275, 810.
(5) Lasic, D. D.; Templeton, N. S. Adv. Drug Delivery Rev. 1996, 20, 221.
(6) Miller, A. D. Angew. Chem. Int. Ed. 1998, 37, 1768.
(7) Chesnoy, S.; Huang, L. Annu. Rev. Biophys. Biomol. Struct. 2000, 29, 27.
(8) Rädler, J. O.; Koltover, I.; Jamieson, A.; Salditt, T.; Safinya, C. R. Langmuir 1998, 14, 4272.
(9) Sternberg, B.; Sorgi, F. L.; Huang, L. FEBS Lett. 1994, 356, 361.
(10) Huang, L.; Hung, M. C.; Wagner, E. Nonviral Vectors for Gene Therapy;
Academic Press: New York, 1999.
(11) Gustafsson, J.; Arvidson, G.; Karlsson, G.; Almgren, M. Biochim. Biophys. Acta
1995, 1235, 305.
(12) Pitard, B.; Aguerre, O.; Airiau, M.; Lachages, A. M.; Boukhnikachvili, T.; Byk,
G.; Dubertret, C.; Herviou, C.; Scherman, D.; Mayaux, J. F.; Crouzet, J. Proc.
Natl. Acad. Sci. U.S.A. 1997, 94, 14412.
(13) Lasic, D. D.; Strey, H.; Stuart, M. C. A.; Podgornik, R.; Frederik, P. M. J. Am.
Chem. Soc. 1997, 119, 832.
(14) Koltover, I.; Salditt, T.; Safinya, C. R. Biophys. J. 1999, 77, 915.
(15) Koltover, I.; Salditt, T.; Rädler, J. O.; Safinya, C. R. Science 1998, 281, 78.
(16) Koltover, I.; Wagner, K.; Safinya, C. R. Proc. Natl. Acad. Sci. U.S.A.
2000, 97, 14046.
(17) Fang, Y.; Yang, J. J. Phys. Chem. B 1997, 101, 441.
(18) Fang, Y.; Yang, J. J. Phys. Chem. B 1997, 101, 3453.
(19) Malghani, M. S.; Yang, J. J. Phys. Chem. B 1998, 102, 8930.
(20) Fang, Y.; Hoh, J. H. J. Am. Chem. Soc. 1998, 120, 8903.
(21) Ono. M. Y.; Spain, E. M. J. Am. Chem. Soc. 1999, 121, 7330.
(22) Leonenko, Z. V.; Merkle, D.; Lees-Miller, S. P.; Cramb, D. T. Langmuir
2002, 18, 4873.
(23) Battersby, B. J.; Grimm, R.; Huebner, S.; Ceve, G. Biochim. Biophys. Acta
1998, 1372, 379.
(24) Huebner, S.; Battersby, B. J.; Grimm, R.; Cevc, G. Biophys. J. 1999, 76, 3158.
(25) Schmutz, M.; Durand, D.; Debin, A.; Palvadeau, Y.; Etienne, A.; Thierry, A. R.
Proc. Natl. Acad. Sci. U.S.A. 1999, 96, 12293.
(26) Pitard, B.; Oudrhiri, N.; Vigneron, J. P.; Hauchecorne, M.; Aguerre, O.; Toury,
R.; Airiau, M.; Ramasawmy, R.; Scherman, D.; Crouzet, J.; Lehn, J. M.; Lehn, P.
Proc. Natl. Acad. Sci. U.S.A. 1999, 96, 2621.
(27) Raspaud, E.; Pitard, B.; Durand, D.; Aguerre-Chariol, O.; Pelta, J.; Byk, G.;
Scherman, D.; Livolant, F. J. Phys. Chem. B 2001, 105, 5291.
(28) Zantl, R.; Baicu, L.; Artzner, F.; Sprenger, I.; Rapp, G.; Rädler, J. O.
J. Phys. Chem. B 1999, 103, 10300.
(29) Liang, H.; Angelini, T. E.; Ho, J.; Braun, P. V.; Wong, G. C. L. J. Am. Chem.
Soc. 2003, 125, 11786.
(30) Gao, X.; Huang, L. Biochem. Biophys. Res. Commun. 1991, 179, 280.
(31) Dias, R.; Mel’nikov, S.; Lindman, B.; Miguel, M. G. Langmuir 2000, 16, 9577.
(32) Medellin-Rodriguez, F. J.; Phillips, P. J.; Lin, J. S. Macromolecules
1996, 29, 7491.
(33) Liou, W.; Geuze, H. J.; Slot, J. W. Histochem. Cell Biol. 1996, 106, 4.
(34) Hayagawa, K.; Santerre, J. P.; Kwak, J. C. T. Macromolecules 1983, 16, 1642.
(35) Chandar, P.; Somasundaran, P.; Turro, N. J. Macromolecules 1988, 21, 950.
(36) Philips, B.; Dawydoff, W.; Linow, K. J. Z. Chem. 1982, 22, 1.
(37) Bakturov, E. A.; Bimendina, L. A. Adv. Polym. Sci. 1982, 41, 99.
(38) Kabanov, V. A.; Zezin, A. B. Makromol. Chem. Suppl. 1984, 6, 259.
(39) Jones, A. A. L. Soft Condensed Matter; Oxford University Press:
New York, 2002.
(40) Podgornik, R.; Rau, D. C.; Parsegian, V. A. Macromolecules 1989, 22, 1780.
(41) Wachtel, E.; Borochov, N.; Bach, D.; Miller, I. R. Chem. Phys. Lipids
1998, 92, 127.
(42) Heller,W. T.;Waring, A. J.; Lehrer, R. I.; Harroun, T. A.;Weiss, T. M.; Yang, L.;
Huang, H. W. Biochemistry 2000, 39, 139.
(43) Pott, T.; Roux, D. FEBS Lett. 2002, 511, 150.
(44) Lewis, R. N. A. H.; Winter, I.; Kriechbaum, M.; Lohner, K.; McElhaney, R. N.
Biophys. J. 2001, 80, 1329.

Chapter 3
(1) Ikkala, O.; Brinke, G. ten. Science 2002, 295, 2407.
(2) Rädler, J. O.; Koltover, I.; Salditt, T.; Safinya, C. R. Science 1997, 275, 810.
(3) Koltover, I.; Salditt, T.; Rädler, J. O.; Safinya, C. R. Science 1998, 281, 78.
(4) Wong, G. C. L.; Tang, J. X.; Lin, A.; Li, Y.; Janmey, P. A.; Safinya, C. R. Science 2000, 288, 2035.; Subramanian, G.; Hjelm, R. P.; Deming, T. J.; Smith, G. S.; Li, Y.; Safinya, C. R. J. Am. Chem. Soc. 2000, 122, 26.
(5) Huang, H. W. Biochemistry 2000, 39, 8347.
(6) Huebner, S.; Battersby, B. J.; Grimm, R.; Cevc, G. Biophys. J. 1999, 76, 3158.; Lasic, D. D.; Strey, H.; Stuart, M. C. A.; Podgornik, R.; Frederik, P. M. J. Am. Chem. Soc. 1997, 119, 832.; Rädler, J. O.; Koltover, I.; Jamieson, A.; Salditt, T.; Safinya, C. R. Langmuir 1998, 14, 4272.; Battersby, B. J.; Grimm, R.; Huebner, S.; Ceve, G. Biochim. Biophys. Acta. 1998, 1372, 379.
(7) Miller, A. D. Angew. Chem. Int. Ed. 1998, 37, 1768.
(8) Salditt, T.; Koltover, I.; Rädler, J. O.; Safinya, C. R. Phys. Rev. Lett. 1997, 79, 2582.
(9) Neat DNA tends to adopt A conformation when the water activity is reduced for the sake of more economical hydration [16].
(10) Gao, X.; Huang, L. Biochem. Biophys. Res. Commun. 1991, 179, 280.
(11) Sinden, R. R. DNA Structure and Function, Academic Press: New York, 1994.
(12) Wu, C. M.; Liou, W.; Chen, H. L.; Lin, T. L.; Jeng, U. S. Macromolecules 2004, 37, 4974.
(13) Wachtel, E.; Borochov, N. Bach, D.; Miller, I. R. Chem. Phys. of Lipids 1998, 92, 127.
(14) Pott, T.; Roux, D. FEBS Lett. 2002, 511, 150.
(15) The cross sectional area of DNA-bound DC-Chol was measured from the surface pressure-area (��-A) isotherm using a Langmuir-Blodgett trough (Nima Technology Model 622D1). We spread 22 �尳 of DC-Chol solution in chloroform (2.5 mg/mL) on a water solution of 1.0 �嵱 DNA, and the monolayer was compressed for recording the ��-A isotherm after 1 hr. The cross sectional area per DC-Chol molecule was estimated from the region where �� started to rise sharply. (The data were kindly provided by Prof. Lin)
(16) Saenger, W.; Hunter, W. N.; Kennard, O. Nature 1986, 324, 385.
(17) Franklin, R. E.; Gosling, R. G. Nature 1953, 172, 156.
(18) Liang, H.; Angelini, T. E.; Ho, J.; Braun, P. V.; Wong, G. C. L. J. Am. Chem. Soc. 2003, 125, 11786.

Chapter 4
(1) Lasic, D. D.; Templeton, N. S. Adv. Drug Delivery Rev. 1996, 20, 221.
(2) Miller, A. D. Angew. Chem. Int. Ed. 1998, 37, 1768.
(3) Chesnoy, S.; Huang, L. Annu. Rev. Biophys. Biomol. Struct. 2000, 29, 27.
(4) Rädler, J. O.; Koltover, I.; Salditt, T.; Safinya, C. R. Science 1997, 275, 810.
(5) Lasic, D. D.; Strey, H.; Stuart, M. C. A.; Podgornik, R.; Frederik, P. M. J. Am. Chem. Soc. 1997, 119, 832.
(6) Koltover, I.; Salditt, T.; Rädler, J. O.; Safinya, C. R. Science 1998, 281, 78.
(7) Rädler, J. O.; Koltover, I.; Jamieson, A.; Salditt, T.; Safinya, C. R. Langmuir 1998, 14, 4272.
(8) Sternberg, B.; Sorgi, F. L.; Huang, L. FEBS Lett. 1994, 356, 361.
(9) Huang, L; Hung, M. C.; Wagner, E. Nonviral Vectors for Gene Therapy, Academic Press: New York, 1999.
(10) Gustafsson, J.; Arvidson, G.; Karlsson, G.; Almgren, M. Biochim. Biophys. Acta.
1995, 1235, 305.
(11) Pitard, B.; Aguerre, O.; Airiau, M.; Lachages, A. M.; Boukhnikachvili, T.; Byk,
G.; Dubertret, C.; Herviou, C.; Scherman, D.; Mayaux, J. F.; Crouzet, J. Proc.
Natl. Acad. Sci. U.S.A. 1997, 94, 14412.
(12) Koltover, I.; Salditt, T.; Safinya, C. R. Biophys. J. 1999, 77, 915.
(13) Koltover, I.; Wagner, K.; Safinya, C. R. Proc. Natl. Acad. Sci. U.S.A. 2000, 97,
14046.
(14) Fang, Y.; Yang, J. J. Phys. Chem. B 1997, 101, 441.
(15) Fang, Y.; Yang, J. J. Phys. Chem. B 1997, 101, 3453.
(16) Fang, Y.; Hoh, J. H. J. Am. Chem. Soc. 1998, 120, 8903.
(17) Ono. M. Y.; Spain, E. M. J. Am. Chem. Soc. 1999, 121, 7330.
(18) Leonenko, Z. V.; Merkle, D.; Lees-Miller, S. P.; Cramb, D. T. Langmuir 2002,
18, 4873.
(19) Battersby, B. J.; Grimm, R.; Huebner, S.; Cevc, G. Biochim. Biophys. Acta.
1998, 1372, 379.
(20) Huebner, S.; Battersby, B. J.; Grimm, R.; Cevc, G. Biophys. J. 1999, 76, 3158.
(21) Schmutz, M.; Durand, D.; Debin, A.; Palvadeau, Y.; Etienne, A.; Thierry, A. R.
Proc. Natl. Acad. Sci. U.S.A. 1999, 96, 12293.
(22) Pitard, B.; Oudrhiri, N.; Vigneron, J. P.; Hauchecorne, M.; Aguerre, O.; Toury,
R.; Airiau, M.; Ramasawmy, R.; Scherman, D.; Crouzet, J.; Lehn, J. M.; Lehn,
P. Proc. Natl. Acad. Sci. U.S.A. 1999, 96, 2621.
(23) Raspaud, E.; Pitard, B.; Durand, D.; Aguerre-Chariol, O.; Pelta, J.; Byk,
G.; Scherman, D.; Livolant, F. J. Phys. Chem. B 2001, 105, 5291.
(24) Zantl, R.; Baicu, L.; Artzner, F.; Sprenger, I.; Rapp, G.; Rädler, J. O.
J. Phys. Chem. B 1999, 103, 10300.
(25) Pott, T.; Roux, D. FEBS Lett. 2002, 511, 150.
(26) Monnard, P.; Berclaz, N.; Conde-Frieboes, K.; Oberholzer, T. Langmuir 1999,
15, 7504.
(27) Malghani, M. S.; Yang, J. J. Phys. Chem. B 1998, 102, 8930.
(28) Tarahovsky, Y. S.; Khusainova, R. S.; Gorelov, A. V.; Nicolaeva, T. I.; Deev,
A. A.; Dawson, A. K.; Ivanitsky, G. R. FEBS Lett. 1996, 390, 133.
(29) Kharakoz, D. P.; Khusainova, R. S.; Gorelov, A. V.; Dawson, K. A.
FEBS Lett. 1999, 446, 27.
(30) Hayes, M. E.; Gorelov, A. V.; Dawson, K. A. Progr. Colloid Polym. Sci.
2001, 118, 243.
(31) Francescangeli, O.; Stanic, V.; Gobbi, L.; Bruni, P.; Iacussi, M.; Tosi, G.
Phys. Rev. E 2003, 67, 011904.
(32) McManus, J. J.; Rädler, J. O.; Dawson, K. A. J. Phys. Chem. B 2003, 107, 9869.
(33) Dias, R.; Mel’nikov, S.; Lindman, B.; Miguel, M. G. Langmuir 2000, 16, 9577.
(34) Medellin-Rodriguez, F. J.; Phillips, P. J.; Lin, J. S. Macromolecules 1996,
29, 7491.
(35) Liou, W.; Geuze, H. J.; Slot, J. W. Histochem. Cell Biol. 1996, 106, 41.
(36) Wu, C. M.; Liou, W.; Chen, H. L.; Lin, T. L.; Jeng, U. S. Macromolecules
2004, 37, 4974.

Chapter 5
(1) Lasic, D. D.; Templeton, N. S. Adv. Drug Delivery Rev. 1996, 20, 221.
(2) Miller, A. D. Angew. Chem. Int. Ed. 1998, 37, 1768.
(3) Chesnoy, S.; Huang, L. Annu. Rev. Biophs. Biomol. Struct. 2000, 29, 27.
(4) Rädler, J. O.; Koltover, I.; Salditt, T.; Safinya, C. R. Science 1997, 275, 810.
(5) Lasic, D. D.; Strey, H.; Stuart, M. C. A.; Podgornik, R.; Frederik, P. M. J. Am. Chem. Soc. 1997, 119, 832.
(6) Koltover, I.; Salditt, T.; Rädler, J. O.; Safinya, C. R. Science 1998, 281, 78.
(7) Rädler, J. O.; Koltover, I.; Jamieson, A.; Salditt, T.; Safinya, C. R. Langmuir 1998, 14, 4272.
(8) Sternberg, B.; Sorgi, F. L.; Huang, L. FEBS Lett. 1994, 356, 361.
(9) Huang, L; Hung, M. C.; Wagner, E. Nonviral Vectors for Gene Therapy, Academic Press: New York, 1999.
(10) Gustafsson, J.; Arvidson, G.; Karlsson, G.; Almgren, M. Biochim. Biophys.
Acta 1995, 1235, 305.
(11) Pitard, B.; Aguerre, O.; Airiau, M.; Lachages, A. M.; Boukhnikachvili, T.;
Byk, G.; Dubertret, C.; Herviou, C.; Scherman, D.; Mayaux, J. F.; Crouzet, J.
Proc. Natl. Acad. Sci. U.S.A. 1997, 94, 14412.
(12) Koltover, I.; Salditt, T.; Safinya, C. R. Biophys. J. 1999, 77, 915.
(13) Koltover, I.; Wagner, K.; Safinya, C. R. Proc. Natl. Acad. Sci. U.S.A. 2000,
97, 14046.
(14) Fang, Y.; Yang, J. J. Phys. Chem. B 1997, 101, 441.
(15) Fang, Y.; Yang, J. J. Phys. Chem. B 1997, 101, 3453.
(16) Fang, Y.; Hoh, J. H. J. Am. Chem. Soc. 1998, 120, 8903.
(17) Ono. M. Y.; Spain, E. M. J. Am. Chem. Soc. 1999, 121, 7330.
(18) Leonenko, Z. V.; Merkle, D.; Lees-Miller, S. P.; Cramb, D. T. Langmuir
2002, 18, 4873.
(19) Battersby, B. J.; Grimm, R.; Huebner, S.; Cevc, G. Biochim. Biophys. Acta
1998, 1372, 379.
(20) Huebner, S.; Battersby, B. J.; Grimm, R.; Cevc, G. Biophys. J.
1999, 76, 3158.
(21) Schmutz, M.; Durand, D.; Debin, A.; Palvadeau, Y.; Etienne, A.; Thierry, A. R.
Proc. Natl. Acad. Sci. U.S.A.1999, 96, 12293.
(22) Pitard, B.; Oudrhiri, N.; Vigneron, J. P.; Hauchecorne, M.; Aguerre, O.;
Toury, R.; Airiau, M.; Ramasawmy, R.; Scherman, D.; Crouzet, J.;
Lehn, J. M.; Lehn, P. Proc. Natl. Acad. Sci. U.S.A. 1999, 96, 2621.
(23) Raspaud, E.; Pitard, B.; Durand, D.; Aguerre-Chariol, O.; Pelta, J.;
Byk, G.; Scherman, D.; Livolant, F. J. Phys. Chem. B 2001, 105, 5291.
(24) Zantl, R.; Baicu, L.; Artzner, F.; Sprenger, I.; Rapp, G.; Rädler, J. O.
J. Phys. Chem. B 1999, 103, 10300.
(25) Lin, A. J.; Slack, N. L.; Ahmad, A.; George, C. X.; Samuel, C. E.;
Safinya, C. R. Biophys. J. 2003, 84, 3307.
(26) Bloomfield, V. A. Curr. Opinion Struct. Biol. 1996, 6, 334.
(27) Bloomfield, V. A. Biopolymers 1997, 44, 269.
(28) Rau, D. C.; Parsegian V. A. Biophys. J. 1992, 51, 246.
(29) Dias, R.; Mel’nikov, S.; Lindman, B.; Miguel, M. G. Langmuir
2000, 16, 9577.
(30) Liou, W.; Geuze, H. J.; Slot, J. W. Histochem. Cell Biol. 1996, 106, 41.
(31) Medellin-Rodriguez, F. J.; Phillips, P. J.; Lin, J. S. Macromolecules
1996, 29, 7491.
(32) Podgornik, R.; Rau, D. C.; Parsegian, V. A. Macromolecules 1989, 22, 1780.
(33) Strey, H. H.; Parsegian, V. A.; Podgornik, R.; Phys. Rev. Lett. 1997, 78, 895.
(34) Ghosh, Y. K.; Indi, S. S.; Bhattacharya, S. J. Phys. Chem. B 2001,
105, 10257.
(35) Paré, C.; Lafleur, M. Langmuir 2001, 17, 5587.
(36) Linseisen, F. M.; Thewalt, J. L.; Bloom, M.; Bayerl, T. M. Chem. Phys.
Lipids 1993, 65, 141.
(37) Binder, W. H.; Barragan, V.; Menger, F. M. Angew. Chem. Int. Ed.
2003, 42, 5802.
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