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Giona RM, Vitorazi L, Loh W. Assessing the Contribution of the Neutral Blocks in DNA/Block-Copolymer Polyplexes: Poly(acrylamide) vs. Poly(ethylene Oxide). Molecules 2023; 28:molecules28010398. [PMID: 36615592 PMCID: PMC9824764 DOI: 10.3390/molecules28010398] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Revised: 12/24/2022] [Accepted: 12/26/2022] [Indexed: 01/04/2023] Open
Abstract
The interaction of DNA with different block copolymers, namely poly (trimethylammonium chloride methacryloyoxy)ethyl)-block-poly(acrylamide), i.e., (PTEA)-b-(PAm), and poly (trimethylammonium chloride methacryloyoxy)ethyl)-block-poly(ethylene oxide), i.e., (PTEA)-b-(PEO), was studied. The nature of the cationic block was maintained fixed (PTEA), whereas the neutral blocks contained varying amounts of acrylamide or (ethylene oxide) units. According to results from isothermal titration microcalorimetry measurements, the copolymers interaction with DNA is endothermic with an enthalpy around 4.0 kJ mol−1 of charges for (PTEA)-b-(PAm) and 5.5 kJ mol−1 of charges for (PTEA)-b-(PEO). The hydrodynamic diameters of (PTEA)-b-(PEO)/DNA and (PTEA)-b-(PAm)/DNA polyplexes prepared by titration were around 200 nm at charge ratio (Z+/−) < 1. At Z+/− close and above 1, the (PTEA)50-b-(PAm)50/DNA and (PTEA)50-b-(PAm)200/DNA polyplexes precipitated. Interestingly, (PTEA)50-b-(PAm)1000/DNA polyplexes remained with a size of around 300 nm even after charge neutralization, probably due to the size of the neutral block. Conversely, for (PTEA)96-b-(PEO)100/DNA polyplexes, the size distribution was broad, indicating a more heterogeneous system. Polyplexes were also prepared by direct mixture at Z+/− of 2.0, and they displayed diameters around 120−150 nm, remaining stable for more than 10 days. Direct and reverse titration experiments showed that the order of addition affects both the size and charge of the resulting polyplexes.
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Affiliation(s)
- Renata Mello Giona
- LaMaFI—Laboratório de Materiais e Fenômenos de Interface, Chemistry Department, Universidade Tecnológica Federal do Paraná (UTFPR), Medianeira, Curitiba 85884-000, Paraná (PR), Brazil
- Institute of Chemistry, Universidade Estadual de Campinas (UNICAMP), Caixa Postal 6154, Campinas 13083-970, São Paulo State (SP), Brazil
| | - Letícia Vitorazi
- Institute of Chemistry, Universidade Estadual de Campinas (UNICAMP), Caixa Postal 6154, Campinas 13083-970, São Paulo State (SP), Brazil
- Laboratório de Materiais Poliméricos, EEIMVR, Universidade Federal Fluminense, Volta Redonda 27255-125, Rio de Janeiro (RJ), Brazil
| | - Watson Loh
- Institute of Chemistry, Universidade Estadual de Campinas (UNICAMP), Caixa Postal 6154, Campinas 13083-970, São Paulo State (SP), Brazil
- Correspondence:
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Calcium mediated DNA binding in non-lamellar structures formed by DOPG/glycerol monooleate. Chem Phys Lipids 2021; 239:105118. [PMID: 34280362 DOI: 10.1016/j.chemphyslip.2021.105118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 05/28/2021] [Accepted: 07/14/2021] [Indexed: 11/21/2022]
Abstract
In order to test an encapsulation method of short fragmented DNA (∼ 20-300 bp), we study the solubilisation in 150 mM solution of NaCl of a cubic phase formed by glycerol monooleate (GMO) with negatively charged dioleoylphosphatidylglycerol (DOPG) up to the level of unilamellar vesicles and, subsequently, the restoration of the cubic phase using Ca2+ cations. We performed small angle X-ray and neutron scattering (SAXS and SANS) to follow structural changes in DOPG/GMO mixtures induced by increasing DOPG content. The cubic phase (Pn3m space group) is preserved up to ∼ 11 mol% of DOPG in DOPG/GMO. Above 20 mol%, the SANS curves are typical of unilamellar vesicles. The thickness of the DOPG/GMO lipid bilayer (dL) decreases slightly with increasing fraction of DOPG. The addition of 15 mM of CaCl2 solution shields the electrostatic repulsions of DOPG molecules, increases slightly dL and restores the cubic structures in the mixtures up to ∼ 37 mol% of DOPG. Zeta potential shows negative surface charge. The analysis of the data provides the radius of the water nano-channels of the formed non-lamellar structures. We discuss their dimensions with respect to DNA binding. In addition, Ca2+ mediates DNA - DOPG/GMO binding. The formed hexagonal phase, HII, binds less of DNA in comparison with cubic phases (∼ 6 wt% and ∼ 20 wt% of the total amount, respectively). The studied system can be utilized as anionic QII delivery vector for genetic material.
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Ramirez RER, Orth ES, Pires C, Zawadzki SF, de Freitas RA. DODAB-DOPE liposome surface coating using in-situ acrylic acid polymerization. J Mol Liq 2021. [DOI: 10.1016/j.molliq.2021.115689] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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4
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Lipid-Nucleic Acid Complexes: Physicochemical Aspects and Prospects for Cancer Treatment. Molecules 2020; 25:molecules25215006. [PMID: 33126767 PMCID: PMC7662579 DOI: 10.3390/molecules25215006] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Revised: 10/26/2020] [Accepted: 10/27/2020] [Indexed: 12/11/2022] Open
Abstract
Cancer is an extremely complex disease, typically caused by mutations in cancer-critical genes. By delivering therapeutic nucleic acids (NAs) to patients, gene therapy offers the possibility to supplement, repair or silence such faulty genes or to stimulate their immune system to fight the disease. While the challenges of gene therapy for cancer are significant, the latter approach (a type of immunotherapy) starts showing promising results in early-stage clinical trials. One important advantage of NA-based cancer therapies over synthetic drugs and protein treatments is the prospect of a more universal approach to designing therapies. Designing NAs with different sequences, for different targets, can be achieved by using the same technologies. This versatility and scalability of NA drug design and production on demand open the way for more efficient, affordable and personalized cancer treatments in the future. However, the delivery of exogenous therapeutic NAs into the patients’ targeted cells is also challenging. Membrane-type lipids exhibiting permanent or transient cationic character have been shown to associate with NAs (anionic), forming nanosized lipid-NA complexes. These complexes form a wide variety of nanostructures, depending on the global formulation composition and properties of the lipids and NAs. Importantly, these different lipid-NA nanostructures interact with cells via different mechanisms and their therapeutic potential can be optimized to promising levels in vitro. The complexes are also highly customizable in terms of surface charge and functionalization to allow a wide range of targeting and smart-release properties. Most importantly, these synthetic particles offer possibilities for scaling-up and affordability for the population at large. Hence, the versatility and scalability of these particles seem ideal to accommodate the versatility that NA therapies offer. While in vivo efficiency of lipid-NA complexes is still poor in most cases, the advances achieved in the last three decades are significant and very recently a lipid-based gene therapy medicine was approved for the first time (for treatment of hereditary transthyretin amyloidosis). Although the path to achieve efficient NA-delivery in cancer therapy is still long and tenuous, these advances set a new hope for more treatments in the future. In this review, we attempt to cover the most important biophysical and physicochemical aspects of non-viral lipid-based gene therapy formulations, with a perspective on future cancer treatments in mind.
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Feng J, Xu L, Wang H, Liu S. Interaction between Gemini Dodecyl O-Glucosides-Based Multilayer Vesicles and β-Lactoglobulin: The Dominant Role of Surface Charge. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2019; 67:844-855. [PMID: 30607932 DOI: 10.1021/acs.jafc.8b03180] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Novel Gemini dodecyl O-glucoside-based primary, secondary, and tertiary vesicles were developed in this work utilizing layer-by-layer deposition of polysaccharides (e.g., sodium carboxymethyl cellulose and chitosan), and their interaction with β-lactoglobulin (BLG) was carefully investigated. The increase of polysaccharide layers on primary vesicles led to a monotonic increase in size and consecutive reversal of surface charge. Polysaccharide deposition significantly retarded the vesicle aggregation and degradation of entrapped catechin laurate during storage. Steady-state fluorescence, isothermal titration calorimetry, and protein precipitation analyses revealed the surface charge dependence of the interactions between vesicles and a model milk protein BLG, which were much stronger when they were charged oppositely than when they presented the same type of surface charge. It was highlighted that the surface charge of vesicles could be tuned by differently charged coatings to accommodate to that of the milk proteins in the food matrix. This work will contribute to the practical application of niosomal vesicles loaded with bioactive compounds to fortify dairy products.
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Affiliation(s)
- Jin Feng
- Department of Food Science and Nutrition, Fuli Institute of Food Science, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang R&D Center for Food Technology and Equipment , Zhejiang University , 866 Yuhangtang Road , Hangzhou 310058 , China
- Department of Functional Food and Bio-active Compounds, Institute of Agro-food Processing , Jiangsu Academy of Agricultural Sciences , Nanjing 210014 , Jiangsu , China
| | - Lujing Xu
- Department of Food Science and Nutrition, Fuli Institute of Food Science, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang R&D Center for Food Technology and Equipment , Zhejiang University , 866 Yuhangtang Road , Hangzhou 310058 , China
| | - Hua Wang
- Center of Analysis and Measurement , Zhejiang University , 866 Yuhangtang Road , Hangzhou 310058 , China
| | - Songbai Liu
- Department of Food Science and Nutrition, Fuli Institute of Food Science, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang R&D Center for Food Technology and Equipment , Zhejiang University , 866 Yuhangtang Road , Hangzhou 310058 , China
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6
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Lounis FM, Chamieh J, Leclercq L, Gonzalez P, Geneste A, Prelot B, Cottet H. Interactions between Oppositely Charged Polyelectrolytes by Isothermal Titration Calorimetry: Effect of Ionic Strength and Charge Density. J Phys Chem B 2017; 121:2684-2694. [DOI: 10.1021/acs.jpcb.6b11907] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
- Feriel Meriem Lounis
- Institut
des Biomolécules Max Mousseron (IBMM), UMR 5247 CNRS, Université de Montpellier, Ecole Nationale Supérieure de Chimie de Montpellier, Place Eugène Bataillon, CC
1706, 34095 Montpellier
Cedex 5, France
| | - Joseph Chamieh
- Institut
des Biomolécules Max Mousseron (IBMM), UMR 5247 CNRS, Université de Montpellier, Ecole Nationale Supérieure de Chimie de Montpellier, Place Eugène Bataillon, CC
1706, 34095 Montpellier
Cedex 5, France
| | - Laurent Leclercq
- Institut
des Biomolécules Max Mousseron (IBMM), UMR 5247 CNRS, Université de Montpellier, Ecole Nationale Supérieure de Chimie de Montpellier, Place Eugène Bataillon, CC
1706, 34095 Montpellier
Cedex 5, France
| | - Philippe Gonzalez
- Institut
des Biomolécules Max Mousseron (IBMM), UMR 5247 CNRS, Université de Montpellier, Ecole Nationale Supérieure de Chimie de Montpellier, Place Eugène Bataillon, CC
1706, 34095 Montpellier
Cedex 5, France
| | - Amine Geneste
- Institut
Charles Gerhardt de Montpellier, UMR 5253 CNRS-UM-ENSCM, Université de Montpellier, CC1502, Place Eugène Bataillon, 34095 Montpellier, France
| | - Benedicte Prelot
- Institut
Charles Gerhardt de Montpellier, UMR 5253 CNRS-UM-ENSCM, Université de Montpellier, CC1502, Place Eugène Bataillon, 34095 Montpellier, France
| | - Hervé Cottet
- Institut
des Biomolécules Max Mousseron (IBMM), UMR 5247 CNRS, Université de Montpellier, Ecole Nationale Supérieure de Chimie de Montpellier, Place Eugène Bataillon, CC
1706, 34095 Montpellier
Cedex 5, France
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Decoration of gemini alkyl O-glucosides based vesicles by electrostatic deposition of sodium carboxymethyl cellullose: Mechanism, structure and improved stability. Food Hydrocoll 2016. [DOI: 10.1016/j.foodhyd.2016.03.012] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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8
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Rozenfeld JHK, Duarte EL, Barbosa LRS, Lamy MT. The effect of an oligonucleotide on the structure of cationic DODAB vesicles. Phys Chem Chem Phys 2015; 17:7498-506. [PMID: 25706300 DOI: 10.1039/c4cp05652c] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The effect of a small single-stranded oligonucleotide (ODN) on the structure of cationic DODAB vesicles was investigated by means of differential scanning calorimetry (DSC), small angle X-ray scattering (SAXS) and electron spin resonance (ESR) spectroscopy. ODN adsorption induced coalescence of vesicles and formation of multilamellar structures with close contact between lamellae. It also increased the phase transition temperature by 10 °C but decreased transition cooperativity. The ODN rigidified and stabilized the gel phase. In the fluid phase, a simultaneous decrease of ordering close to the bilayer surface and increase in bilayer core rigidity was observed in the presence of the ODN. These effects may be due not only to electrostatic shielding of DODAB head groups but also to superficial dehydration of the bilayers. The data suggest that oligonucleotides may induce the formation of a multilamellar poorly hydrated coagel-like phase below phase transition. These effects should be taken into account when planning ODN delivery employing cationic bilayer carriers.
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9
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de Jesus MB, Zuhorn IS. Solid lipid nanoparticles as nucleic acid delivery system: Properties and molecular mechanisms. J Control Release 2015; 201:1-13. [DOI: 10.1016/j.jconrel.2015.01.010] [Citation(s) in RCA: 88] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2014] [Revised: 01/06/2015] [Accepted: 01/07/2015] [Indexed: 01/19/2023]
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10
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Synthesis, Micellization Behaviour, DNA/RNA Binding and Biological Studies of a Surfactant Cobalt(III) Complex With Dipyrido[3,2-a:2′,4′-c](6,7,8,9-tetrahydro)phenazine. J Fluoresc 2014; 24:1701-14. [DOI: 10.1007/s10895-014-1457-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2014] [Accepted: 09/08/2014] [Indexed: 11/25/2022]
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11
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Janich C, Wölk C, Taßler S, Drescher S, Meister A, Brezesinski G, Dobner B, Langner A. Composites of malonic acid diamides and phospholipids - Structural parameters for optimal transfection efficiency in A549 cells. EUR J LIPID SCI TECH 2014. [DOI: 10.1002/ejlt.201300405] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Christopher Janich
- Martin Luther University (MLU) Halle-Wittenberg; Institute of Pharmacy; Halle (Saale) Germany
| | - Christian Wölk
- Martin Luther University (MLU) Halle-Wittenberg; Institute of Pharmacy; Halle (Saale) Germany
| | - Stephanie Taßler
- Max Planck Institute of Colloids and Interfaces; Potsdam Germany
| | - Simon Drescher
- Martin Luther University (MLU) Halle-Wittenberg; Institute of Pharmacy; Halle (Saale) Germany
| | - Annette Meister
- Centre for Structure and Dynamics of Proteins (MZP); MLU Halle-Wittenberg; Halle (Saale) Germany
| | | | - Bodo Dobner
- Martin Luther University (MLU) Halle-Wittenberg; Institute of Pharmacy; Halle (Saale) Germany
| | - Andreas Langner
- Martin Luther University (MLU) Halle-Wittenberg; Institute of Pharmacy; Halle (Saale) Germany
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12
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Wölk C, Pawlowska D, Drescher S, Auerswald A, Meister A, Hause G, Blume A, Langner A, Brezesinski G, Dobner B. New micellar transfection agents. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2014; 30:4905-4915. [PMID: 24697720 DOI: 10.1021/la404860w] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Two novel micelle-forming amino-functionalized lipids (OT6 and TT6) bearing two alkyl chains connected to a large positively charged hexavalent headgroup, which might be interesting polynucleotide transferring agents with the advantage of an easy and reproducible production of micelle dispersions, have been characterized. The critical micelle concentration (cmc) of both lipids has been determined by two different methods, namely, isothermal titration calorimetry (ITC) and 1,6-diphenyl-1,3,5-hexatriene (DPH) fluorescence experiments. In addition, the lipid dispersions were studied as a function of temperature using differential scanning calorimetry (DSC), dynamic light scattering (DLS), Fourier-transform infrared (FT-IR) spectroscopy, and cryo-transmission electron microscopy (cryo-TEM). The OT6 and TT6 micelles effectively complex DNA as determined by ITC and DSC measurements. In addition, DLS and ζ-potential measurements were performed to determine lipoplex formulations that exhibit colloidal stability. Finally, the structures of OT6/DNA complexes were investigated by means of X-ray scattering and TEM.
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Affiliation(s)
- Christian Wölk
- Institute of Pharmacy, Martin-Luther-Universitaet (MLU) Halle-Wittenberg , Wolfgang-Langenbeck-Strasse 4, 06120 Halle (Saale), Germany
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13
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Priftis D, Megley K, Laugel N, Tirrell M. Complex coacervation of poly(ethylene-imine)/polypeptide aqueous solutions: Thermodynamic and rheological characterization. J Colloid Interface Sci 2013; 398:39-50. [DOI: 10.1016/j.jcis.2013.01.055] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2012] [Revised: 01/25/2013] [Accepted: 01/28/2013] [Indexed: 10/27/2022]
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14
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How cationic lipids transfer nucleic acids into cells and across cellular membranes: Recent advances. J Control Release 2013; 166:46-56. [DOI: 10.1016/j.jconrel.2012.12.014] [Citation(s) in RCA: 152] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2012] [Revised: 12/06/2012] [Accepted: 12/10/2012] [Indexed: 12/16/2022]
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15
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Dabkowska AP, Barlow DJ, Campbell RA, Hughes AV, Quinn PJ, Lawrence MJ. Effect of Helper Lipids on the Interaction of DNA with Cationic Lipid Monolayers Studied by Specular Neutron Reflection. Biomacromolecules 2012; 13:2391-401. [DOI: 10.1021/bm300639n] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- A. P. Dabkowska
- Institute of Pharmaceutical
Science, School of Biomedical Sciences, King’s College London, 150 Stamford Street, London, SE1 9NH,
U.K
| | - D. J. Barlow
- Institute of Pharmaceutical
Science, School of Biomedical Sciences, King’s College London, 150 Stamford Street, London, SE1 9NH,
U.K
| | - R. A. Campbell
- Institut Laue-Langevin, B.P. 156, 38042 Grenoble Cedex, France
| | - A. V. Hughes
- ISIS, Rutherford Appleton Laboratory, Chilton, Didcot, OX11 OQX, U.K
| | - P. J. Quinn
- Institute of Pharmaceutical
Science, School of Biomedical Sciences, King’s College London, 150 Stamford Street, London, SE1 9NH,
U.K
| | - M. J. Lawrence
- Institute of Pharmaceutical
Science, School of Biomedical Sciences, King’s College London, 150 Stamford Street, London, SE1 9NH,
U.K
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16
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Alves FR, Loh W. Vesicles prepared with the complex salts dioctadecyldimethylammonium polyacrylates. J Colloid Interface Sci 2012; 368:292-300. [DOI: 10.1016/j.jcis.2011.11.020] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2011] [Revised: 11/09/2011] [Accepted: 11/09/2011] [Indexed: 11/25/2022]
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17
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Fluorescence methods for lipoplex characterization. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2011; 1808:2694-705. [DOI: 10.1016/j.bbamem.2011.07.020] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2011] [Revised: 06/29/2011] [Accepted: 07/15/2011] [Indexed: 11/24/2022]
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18
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Interaction of cationic bilayer fragments with a model oligonucleotide. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2011; 1808:649-55. [DOI: 10.1016/j.bbamem.2010.11.036] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2010] [Revised: 11/26/2010] [Accepted: 11/30/2010] [Indexed: 11/15/2022]
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19
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Li F, Luan Y, Liu X, Xu G, Li X, Li X, Wang J. Investigation on the aggregation behaviors of DDAB/NaDEHP catanionic vesicles in the absence and presence of a negatively charged polyelectrolyte. Phys Chem Chem Phys 2011; 13:5897-905. [DOI: 10.1039/c0cp01365j] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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20
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Tarahovsky YS. Cell transfection by DNA-lipid complexes — Lipoplexes. BIOCHEMISTRY (MOSCOW) 2010; 74:1293-304. [DOI: 10.1134/s0006297909120013] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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21
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Michanek A, Kristen N, Höök F, Nylander T, Sparr E. RNA and DNA interactions with zwitterionic and charged lipid membranes - a DSC and QCM-D study. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2009; 1798:829-38. [PMID: 20036213 DOI: 10.1016/j.bbamem.2009.12.009] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2009] [Revised: 11/12/2009] [Accepted: 12/15/2009] [Indexed: 10/20/2022]
Abstract
The aim of the present study is to establish under which conditions tRNA associates with phospholipid bilayers, and to explore how this interaction influences the lipid bilayer. For this purpose we have studied the association of tRNA or DNA of different sizes and degrees of base pairing with a set of model membrane systems with varying charge densities, composed of zwitterionic phosphatidylcholines (PC) in mixtures with anionic phosphatidylserine (PS) or cationic dioctadecyl-dimethyl-ammoniumbromide (DODAB), and with fluid or solid acyl-chains (oleoyl, myristoyl and palmitoyl). To prove and quantify the attractive interaction between tRNA and model-lipid membrane we used quartz crystal microbalance with dissipation (QCM-D) monitoring to study the tRNA adsorption to deposit phospholipid bilayers from solutions containing monovalent (Na(+)) or divalent (Ca(2+)) cations. The influence of the adsorbed polynucleic acids on the lipid phase transitions and lipid segregation was studied by means of differential scanning calorimetry (DSC). The basic findings are: i) tRNA adsorbs to zwitterionic liquid-crystalline and gel-phase phospholipid bilayers. The interaction is weak and reversible, and cannot be explained only on the basis of electrostatic attraction. ii) The adsorbed amount of tRNA is higher for liquid-crystalline bilayers compared to gel-phase bilayers, while the presence of divalent cations show no significant effect on the tRNA adsorption. iii) The adsorption of tRNA can lead to segregation in the mixed 1,2-dimyristoyl-sn-glycerol-3-phosphatidylcholine (DMPC)-1,2-dimyristoyl-sn-glycero-3-phosphatidylserine (DMPS) and DMPC-DODAB bilayers, where tRNA is likely excluded from the anionic DMPS-rich domains in the first system, and associated with the cationic DODAB-rich domains in the second system. iv) The addition of shorter polynucleic acids influence the chain melting transition and induce segregation in a mixed DMPC-DMPS system, while larger polynucleic acids do not influence the melting transition in these system. The results in this study on tRNA-phospholipid interactions can have implications for understanding its biological function in, e.g., the cell nuclei, as well as in applications in biotechnology and medicine.
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Affiliation(s)
- Agnes Michanek
- Physical Chemistry 1, Lund University, P.O. Box 124, 22100 Lund, Sweden.
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22
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Giatrellis S, Nikolopoulos G, Sideratou Z, Nounesis G. Calorimetric study of the interaction of binary DMTAP/DOTAP cationic liposomes with plasmid DNA. J Liposome Res 2009; 19:220-30. [DOI: 10.1080/08982100902746596] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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23
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Bernardes JS, Loh W. Structure and phase equilibria of mixtures of the complex salt hexadecyltrimethylammonium polymethacrylate, water and different oils. J Colloid Interface Sci 2008; 318:411-20. [DOI: 10.1016/j.jcis.2007.10.030] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2007] [Revised: 10/16/2007] [Accepted: 10/18/2007] [Indexed: 10/22/2022]
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24
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Grueso E, Sanchez F. DNA−Surfactant Interactions: A Procedure for Determination Group Contributions. J Phys Chem B 2007; 112:698-702. [DOI: 10.1021/jp0738457] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Elia Grueso
- The Department of Physical Chemistry, University of Seville, C/Profesor García González s/n, 41012, Seville, Spain
| | - Francisco Sanchez
- The Department of Physical Chemistry, University of Seville, C/Profesor García González s/n, 41012, Seville, Spain
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25
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Arsac F, Hidaka H. DNA damage photoinduced by titanium dioxide in the presence of anionic vesicles under uv illumination: influence of sodium chloride concentration. J Oleo Sci 2007; 56:595-601. [PMID: 17938550 DOI: 10.5650/jos.56.595] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The DNA damage caused by TiO2 under in vitro conditions by UV-A exposure in the presence of anionic vesicles of Aerosol OT (AOT) was investigated. The supercoiled form (S) in DNA plasmids was converted to the linear form (L) via the relaxed form (R). The DNA damage was slower in the presence of AOT vesicles prepared in aqueous NaCl solution. Moreover, the presence of AOT vesicles in solution after 6 h of UV irradiation was confirmed with an optical microscope. Probably, a fraction of the DNA was protected by random trapping during sonication. However, the addition of NaCl needed for the vesicle formation can decrease the TiO2 activity. On the other hand, in the absence of vesicles the NaCl concentration led to a profound influence on the adsorption of DNA onto the TiO2 surface. During UV irradiation, the degradation rate of DNA increased with increasing the salt concentration. Solutions containing vesicles were prepared at various NaCl concentrations between 10 mM and 75 mM. Consequently, the salt concentration had no significant effect on the DNA damage. The presence of NaCl can play a deleterious role during the photoinduced process. However, the encapsulation of a fraction of DNA is not excluded. In such conditions, the DNA could be protected against the reactive oxygen species.
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Affiliation(s)
- Fabrice Arsac
- Frontier Research Center for the Global Environment Science, Meisei University, Hino, Tokyo, Japan
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26
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Saunders M, Taylor KMG, Craig DQM, Palin K, Robson H. High Sensitivity Differential Scanning Calorimetry Study of DNA-Cationic Liposome Complexes. Pharm Res 2007; 24:1954-61. [PMID: 17551810 DOI: 10.1007/s11095-007-9325-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2007] [Accepted: 04/23/2007] [Indexed: 11/28/2022]
Abstract
PURPOSE To investigate plasmid DNA interactions with liposomes prepared from dimyristoylglyceroethylphosphocholine (EDMPC) and DOPE using high sensitivity differential scanning calorimetry (HSDSC). MATERIALS AND METHODS Large unilamellar liposomes of EDMPC with DOPE (mol ratio 0-50%) were prepared. Plasmid DNA was added to give a final DNA/lipid (-/+) charge ratio of 0.5. Samples were placed into an HSDSC and cooled to 3 degrees C, held isothermally for 30 min and then the temperature was ramped to 120 degrees C at a rate of 1 degree C/min. RESULTS On heating EDMPC liposomes, the main phase transition occurred at 21.2 degrees C, with a low temperature shoulder on the endothermic peak. At low DOPE concentrations the main phase transition temperatures and enthalpies of transition were lower than for pure EDMPC, with a peak corresponding to a pure EDMPC phase occurring at DOPE concentrations of 12-17 mol%. At 50 mol%, no main transition endotherm was observed. DNA solution produced two endothermic peaks with numerous 'satellite' peaks indicating thermal denaturation. DNA binding to EDMPC changed the shape of the thermogram, indicating alteration in lipid packing within the bilayer. DNA induced demixing in the bilayers of DOPE-containing liposomes. CONCLUSION HSDSC provided information for characterizing liposome formulations and DNA interactions with such vesicles.
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Affiliation(s)
- Mark Saunders
- School of Pharmacy, University of London, 29-39 Brunswick Square, London, UK
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27
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Wang C, Li X, Wettig SD, Badea I, Foldvari M, Verrall RE. Investigation of complexes formed by interaction of cationic gemini surfactants with deoxyribonucleic acid. Phys Chem Chem Phys 2007; 9:1616-28. [PMID: 17429555 DOI: 10.1039/b618579g] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Cationic gemini surfactants, N,N-bis(dimethylalkyl)-alpha,omega-alkanediammonium dibromide [C(m)H(2m+1)(CH(3))(2)N(+)(CH(2))(s)N(+)(CH(3))(2)C(m)H(2m+1) x 2 Br(-), or m-s-m], have proven to be effective synthetic vectors for gene delivery (transfection). Complexes (lipoplexes) of gemini compounds, where m = 12, s = 3, 12 and m = 18 : 1(oleyl), s = 2, 3, 6, with DNA have been investigated using isothermal titration calorimetry (ITC), dynamic light scattering (DLS), zeta potential, atomic force microscopy (AFM) and circular dichroism (CD) techniques. The results show that lipoplex properties depend on the structural properties of the gemini surfactants, the presence of the helper lipid dioleoylphosphatidylethanolamine (DOPE), and the titration sequence. ITC data show that the interaction between DNA and gemini surfactants is endothermic and the observed enthalpy vs. charge ratio profile depends upon the titration sequence. Isoelectric points (IP) of lipoplex formation were estimated from the zeta potential measurements and show good agreement with the reaction endpoints (RP) obtained from ITC. DLS data indicate that DNA is condensed in the lipoplex. AFM images suggest that the lipoplex morphology changes from isolated globular-like aggregated particles to larger-size aggregates with great diversity in morphology. This change is further accentuated by the presence of DOPE in the lipoplexes. The results are interpreted in terms of some current models of lipoplex formation.
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Affiliation(s)
- Chuanzhong Wang
- Central Equipment Laboratory, University of Northern British Columbia, 3333 University Way, Prince George, Canada, BC V2N 4Z9.
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28
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Leal C, Bilalov A, Lindman B. Phase Behavior of a DNA-Based Surfactant Mixed with Water and n-Alcohols. J Phys Chem B 2006; 110:17221-9. [PMID: 16928021 DOI: 10.1021/jp062151f] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The self-assembly behavior of a cationic surfactant (dodecyltrimethylammonium, DTA) with DNA as counterion in mixtures of water and n-alcohols (decanol, octanol, hexanol, butanol, and ethanol) was investigated. The phase diagrams were established and the different regions of the phase diagram characterized with respect to microstructure by (2)H NMR, small-angle X-ray scattering (SAXS), and other techniques. The DNA-DTA surfactant is soluble in all of the studied alcohols, showing increased solubility from decanol down to ethanol. All of the phase diagrams are analogous with respect to the occurrence of liquid crystalline (LC) regions, but the area of the LC region increases as one goes from decanol to ethanol. In all phase diagrams, hexagonal phases (of the reversed type) for the alcohol-rich side and lamellar phases for the other side were detected. For balanced proportions of the components, there is a coexistence of the lamellar and the hexagonal phase, here detected with a double quadrupole splitting in the (2)H NMR spectra. The correctness of the phase diagrams is confirmed by the fact that along the tie-lines the splitting magnitude remains nearly constant. All of the alcohols except for ethanol act as cosurfactants penetrating the DNA-DTA film. Adding salt to the ternary mixtures causes an increase in the unit cell dimension of the lamellar and the hexagonal phases. The phase diagram becomes more complicated when butanol is used for the alcohol phase. Here, there is the occurrence of a new isotropic phase with some properties analogous to those of the disordered sponge (L3) phase obtained for simple surfactant systems.
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Affiliation(s)
- Cecilia Leal
- Physical Chemistry 1, Center of Chemistry and Chemical Engineering, University of Lund, POB 124, Lund 22100, Sweden.
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29
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Interaction of DODAB with neutral phospholipids and cholesterol studied using fluorescence anisotropy. J Photochem Photobiol A Chem 2006. [DOI: 10.1016/j.jphotochem.2005.11.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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30
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Liang H, Harries D, Wong GCL. Polymorphism of DNA-anionic liposome complexes reveals hierarchy of ion-mediated interactions. Proc Natl Acad Sci U S A 2005; 102:11173-8. [PMID: 16061807 PMCID: PMC1183553 DOI: 10.1073/pnas.0502416102] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Self-assembled DNA delivery systems based on anionic lipids (ALs) complexed with DNA mediated by divalent cations have been recently introduced as an alternative to cationic lipid-DNA complexes because of their low cytotoxicity. We investigate AL-DNA complexes induced by different cations by using synchrotron small angle x-ray scattering and confocal microscopy to show how different ion-mediated interactions are expressed in the self-assembled structures and phase behavior of AL-DNA complexes. The governing interactions in AL-DNA systems are complex: divalent ions can mediate strong attractions between different combinations of the components (such as DNA-DNA and membrane-membrane). Moreover, divalent cations can coordinate non-electrostatically with lipids and modify the resultant membrane structure. We find that at low membrane charge densities AL-DNA complexes organize into a lamellar structure of alternating DNA and membrane layers crosslinked by ions. At high membrane charge densities, a new phase with no analog in cationic lipid-DNA systems is observed: DNA is expelled from the complex, and a lamellar stack of membranes and intercalated ions is formed. For a subset of the ionic species, high ion concentrations generate an inverted hexagonal phase comprised of DNA strands wrapped by ion-coated lipid tubes. A simple theoretical model that takes into account the electrostatic and membrane elastic contributions to the free energy shows that this transition is consistent with an ion-induced change in the membrane spontaneous curvature, c0. Moreover, the crossover between the lamellar and inverted hexagonal phases occurs at a critical c0 that agrees well with experimental values.
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Affiliation(s)
- Hongjun Liang
- Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
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31
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Patel MM, Anchordoquy TJ. Contribution of hydrophobicity to thermodynamics of ligand-DNA binding and DNA collapse. Biophys J 2005; 88:2089-103. [PMID: 15653734 PMCID: PMC1305261 DOI: 10.1529/biophysj.104.052100] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The importance of understanding the dynamics of DNA condensation is inherent in the biological significance of DNA packaging in cell nuclei, as well as for gene therapy applications. Specifically, the role of ligand hydrophobicity in DNA condensation has received little attention. Considering that only multivalent cations can induce true DNA condensation, previous studies exploring monovalent lipids have been unable to address this question. In this study we have elucidated the contribution of the hydrophobic effect to multivalent cation- and cationic lipid-DNA binding and DNA collapse by studying the thermodynamics of cobalt hexammine-, spermine-, and lipospermine-plasmid DNA binding at different temperatures. Comparable molar heat capacity changes (DeltaC(p)) associated with cobalt hexammine- and spermine-DNA binding (-23.39 cal/mol K and -17.98 cal/mol K, respectively) suggest that upon binding to DNA, there are insignificant changes in the hydration state of the methylene groups in spermine. In contrast, the acyl chain contribution to the DeltaC(p) of lipospermine-DNA binding (DeltaC(p ) = DeltaC(p lipospermine) - DeltaC(p spermine)) is significant (-220.94 cal/mol K). Although lipopermine induces DNA ordering into "tubular" suprastructures, such structures do not assume toroidal dimensions as observed for spermine-DNA complexes. We postulate that a steric barrier posed by the acyl chains in lipospermine precludes packaging of DNA into dimensions comparable to those found in nature.
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Affiliation(s)
- Mayank M Patel
- Department of Pharmaceutical Sciences, C238 University of Colorado Health Sciences Center, 4200 E. Ninth Ave., Denver, CO 80262, USA.
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32
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Cárdenas M, Campos-Terán J, Nylander T, Lindman B. DNA and cationic surfactant complexes at hydrophilic surfaces. An ellipsometry and surface force study. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2004; 20:8597-8603. [PMID: 15379480 DOI: 10.1021/la0363581] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The adsorption and formation of DNA and cationic surfactant complexes at the silica-aqueous interface have been studied by ellipsometry. The interaction between the DNA-surfactant complexes at the mica-aqueous interface has been determined by the interferometric surface force apparatus. Adsorption was as expected not observed on negatively charged hydrophilic surfaces for DNA and when DNA-cationic surfactant complexes were negatively charged. However, adsorption was observed when there is an excess of cationic surfactant, just below the point of phase separation. The adsorption process requires hours to reach steady state. The adsorbed layer thickness is large at low surface coverage but becomes more compact and thinner at high coverage. A long-range repulsive force was observed between adsorbed layers of DNA-cationic surfactant complexes, which was suggested to be of both electrostatic and steric origin. The forces were found to be dependent on the equilibration time and the experimental pathway.
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Affiliation(s)
- Marité Cárdenas
- Center for Chemistry and Chemical Engineering, Physical Chemistry 1, University of Lund, PO Box 124, SE-221 00, Sweden.
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33
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Affiliation(s)
- Azat Bilalov
- Physical Chemistry 1, Center of Chemistry and Chemical Engineering, University of Lund, POB 124, Lund 22100, Sweden
| | - Cecilia Leal
- Physical Chemistry 1, Center of Chemistry and Chemical Engineering, University of Lund, POB 124, Lund 22100, Sweden
| | - Björn Lindman
- Physical Chemistry 1, Center of Chemistry and Chemical Engineering, University of Lund, POB 124, Lund 22100, Sweden
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34
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Pozharski E, MacDonald RC. Lipoplex thermodynamics: determination of DNA-cationic lipoid interaction energies. Biophys J 2004; 85:3969-78. [PMID: 14645086 PMCID: PMC1303698 DOI: 10.1016/s0006-3495(03)74811-5] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
An experimental study of the cationic lipid-DNA binding affinity is presented. The binding free energy was determined by monitoring lipoplex dissociation under conditions of increasing salt concentration. The primary procedure was based on the extent of quenching by energy transfer of fluorophores on DNA molecules by fluorophore on a lipid as these molecules came into close association in the lipoplex. Titration calorimetry on the Dickerson dodecamer was also done, with results that were in agreement with the fluorescence data. Measurements on short oligonucleotides allowed estimation of the binding energy per nucleotide. The binding free energy is approximately 0.6 kcal/mole nucleotide for the Dickerson dodecamer and declines for longer oligonucleotides. The entropy gained upon complex formation is approximately 1 entropy unit per released counterion. The method was applied to long DNA molecules (herring and lambda-phage DNA) and revealed that complete dissociation occurs at 750 mM NaCl. Likely contributions of macromolecular desolvation and DNA flexibility to the binding energy are discussed.
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Affiliation(s)
- Edwin Pozharski
- Department of Biochemistry, Molecular Biology and Cell Biology, Northwestern University, Evanston, Illinois 60208-3500, USA
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35
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Ow Sullivan MM, Green JJ, Przybycien TM. Development of a novel gene delivery scaffold utilizing colloidal gold–polyethylenimine conjugates for DNA condensation. Gene Ther 2003; 10:1882-90. [PMID: 14502217 DOI: 10.1038/sj.gt.3302083] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
We have developed a novel gene delivery scaffold based on DNA plasmid condensation with colloidal gold/polyethylenimine conjugates. This scaffold system was designed to enable systematic study of the relationships between DNA complex physical properties and transfection efficiency. Using an enhanced green fluorescent protein-coding reporter plasmid and a Chinese hamster ovary cell line, we have measured the transfection efficiencies of our complexes using flow cytometry and their cytotoxicities using the trypan blue assay. We have also assayed complex particle morphologies using atomic force microscopy, photon correlation spectroscopy, and a novel plasmon absorbance peak position analysis. We achieved comparable rates of transfection relative to the commonly used polycationic condensation agents calcium phosphate and LipofectAMINE, with comparably low cytotoxicities. In addition, by manipulating colloidal gold concentration, we could partially decouple complex physical properties including charge ratio, size, DNA loading, and polyethylenimine concentration. Our morphological analyses showed that complexes with a diameter of a few hundred nanometers and a charge ratio of approximately 8 perform best in our transfection efficiency assays. The use of colloidal gold as a component in our delivery system provides a versatile system for manipulating complex properties and morphology as well as a convenient scaffold for planned ligand conjugation studies.
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Affiliation(s)
- M M Ow Sullivan
- Department of Chemical Engineering, Carnegie Mellon University, Pittsburgh, PA 15213, USA
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36
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Barreleiro PCA, May RP, Lindman B. Mechanism of formation of DNA-cationic vesicle complexes. Faraday Discuss 2003; 122:191-201; discussion 269-82. [PMID: 12555857 DOI: 10.1039/b200796g] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Cationic vesicles and DNA form complexes that are promising gene delivery systems. Despite the increasing number of publications on their morphology and structure, the mechanism leading to their formation is not yet understood due to a lack of kinetic data. In the present study the kinetics of the interaction between DNA and cationic vesicles were followed using stopped-flow turbidity and small-angle neutron scattering techniques. The neutron real-time experiments were performed on a high-flux diffractometer, the D22 at the ILL, using a stopped-flow set-up. Extruded mixed vesicles of dimethyldioctadecylammonium bromide (DODAB) with various amounts of dioleoylphosphatidylethanolamine (DOPE) were investigated at 25 degrees C. The results show that the transition from unilamellar vesicles to a multilamellar structure upon DNA addition occurs in three steps. The first step, on the millisecond time scale, is currently not accessible to neutron scattering but was observed by stopped-flow turbidity and fluorescence experiments. The second step, on a time scale of seconds, corresponds to the formation of an intermediate with a locally cylindrical structure. As time progresses this unstable intermediate evolves to a multilamellar structure, on a time scale of minutes. An understanding of the mechanisms behind the DNA-cationic vesicle complex formation event will allow the production of more homogeneous, efficient delivery systems in pharmaceutically acceptable forms.
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Affiliation(s)
- Paula C A Barreleiro
- Centre for Chemistry and Chemical Engineering, Physical Chemistry 1, University of Lund, P. O. Box 124, S-221 00, Lund, Sweden.
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37
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Affiliation(s)
- P. C. A. Barreleiro
- Center for Chemistry and Chemical Engineering, Physical Chemistry 1, University of Lund, P.O. Box 124, 221 00 Lund, Sweden
| | - B. Lindman
- Center for Chemistry and Chemical Engineering, Physical Chemistry 1, University of Lund, P.O. Box 124, 221 00 Lund, Sweden
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38
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Lobo BA, Koe GS, Koe JG, Middaugh CR. Thermodynamic analysis of binding and protonation in DOTAP/DOPE (1:1): DNA complexes using isothermal titration calorimetry. Biophys Chem 2003; 104:67-78. [PMID: 12834828 DOI: 10.1016/s0301-4622(02)00339-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
A better understanding of the nature of the interaction between various cationic lipids used for gene delivery and DNA would lend insight into their structural and physical properties that may modulate their efficacy. We therefore separated the protonation and binding events which occur upon complexation of 1:1 DOTAP (1,2-dioleoyl-3-trimethylammonium propane):DOPE (1,2-dioleoylphosphatidylethanolamine) liposomes to DNA using proton linkage theory and isothermal titration calorimetry (ITC). The enthalpy of DOPE protonation was estimated as -45.0+/-0.7 kJ/mol and the intrinsic binding enthalpy of lipid to DNA as +2.8+/-0.3 kJ/mol. The pK(a) of DOPE was calculated to shift from 7.7+/-0.1 in the free state to 8.8+/-0.1 in the complex. At physiological ionic strength, proton linkage was not observed upon complex formation and the buffer-independent binding enthalpy was +1.0+/-0.4 kJ/mol. These studies indicate that the intrinsic interaction between 1:1 DOTAP/DOPE and DNA is an entropy-driven process and that the affinities of cationic lipids that are formulated with and without DOPE for DNA are controlled by the positive entropic changes that occur upon complex formation.
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Affiliation(s)
- Brian A Lobo
- Department of Pharmaceutical Chemistry, University of Kansas, 2095 Constant Ave., Lawrence, KS 66047, USA
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39
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Pozharski E, MacDonald RC. Thermodynamics of cationic lipid-DNA complex formation as studied by isothermal titration calorimetry. Biophys J 2002; 83:556-65. [PMID: 12080142 PMCID: PMC1302169 DOI: 10.1016/s0006-3495(02)75191-6] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
The detailed analysis of the cationic lipid-DNA complex formation by means of isothermal titration calorimetry is presented. Most experiments were done using 1,2-dioleyl-sn-glycero-3-ethylphosphocholine (EDOPC), but basic titrations were also done using DOTAP, DOTAP:DOPC, and DOTAP:DOPE mixtures. Complex formation was endothermic with less than 1 kcal absorbed per mole of lipid or DNA charge. This enthalpy change was attributed to DNA-DNA mutual repulsion within the lamellar complex. The exception was DOTAP:DOPE-containing lipoplex for which the enthalpy of formation was exothermic, presumably because of DOPE amine group protonation. Experimental conditions, namely, direction and titration increment as well as concentration of titrant, which dictate the structure of resulting lipoplex (whether lamellar complex or DNA-coated vesicle), were found to affect the apparent thermodynamics of complex formation. The structure, in turn, influences the biological properties of the lipoplex. If the titration of lipid into DNA was carried out in large increments, the DeltaH was larger than when the injection increments were smaller, a finding that is consistent with increased vesicle disruption under large increments and which is expected theoretically. Cationic lipid-DNA binding was weak in high ionic strength solutions, however, the effective binding constant is within micromolar range because of macromolecular nature of the interaction.
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Affiliation(s)
- Edwin Pozharski
- Department of Biochemistry, Molecular Biology and Cell Biology, Northwestern University, Evanston, Illinois 60208-3500, USA
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40
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Lobo BA, Rogers SA, Choosakoonkriang S, Smith JG, Koe G, Middaugh CR. Differential scanning calorimetric studies of the thermal stability of plasmid DNA complexed with cationic lipids and polymers. J Pharm Sci 2002; 91:454-66. [PMID: 11835205 DOI: 10.1002/jps.10025] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The thermal stabilities of supercoiled (SC) and linear/open circular (LIN/OC) forms of plasmid DNA when complexed with cationic lipids or cationic polymers used for cellular transfection were assessed using differential scanning calorimetry. Differences in the stability of SC DNA produced by the cationic lipids DOTAP (1,2-dioleoyltrimethyl ammoniumpropane chloride), DSTAP (1,2-distearyltrimethyl ammoniumpropane chloride), and DDAB (dimethyldioctadecylammonium bromide) upon complexation suggest possible effects of headgroup structure on the stability of SC DNA and minimal effects of lipid acyl chain saturation/unsaturation. Complexation of DNA with the cationic polymers polyethylenimine (PEI) or poly-L-lysine (PLL) (but not poly-L-arginine) resulted in a decreased stability of SC DNA when the DNA was in charge excess, although all polymers stabilized SC DNA when the polymer was in charge excess. The effects of these cationic polymers on the stability of SC DNA can be explained by changes produced in the tertiary structure of SC DNA upon binding and may reflect the importance of the topological constraint of supercoiling upon the stability of the resulting complexes.
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Affiliation(s)
- Brian A Lobo
- Department of Pharmaceutical Chemistry, University of Kansas, Lawrence, Kansas 66047, USA
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