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Majewska M, Zamlynny V, Pieta IS, Nowakowski R, Pieta P. Interaction of LL-37 human cathelicidin peptide with a model microbial-like lipid membrane. Bioelectrochemistry 2021; 141:107842. [PMID: 34049238 DOI: 10.1016/j.bioelechem.2021.107842] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Revised: 05/07/2021] [Accepted: 05/09/2021] [Indexed: 10/21/2022]
Abstract
The only representative of cathelicidin peptides in humans is LL-37, a multifunctional antimicrobial peptide (AMP) that is a part of the innate immune response. Details of the LL-37 direct activity against pathogens are not well understood at the molecular level. Here, we present research on the mechanism of interaction between LL-37 and a model multicomponent bilayer lipid membrane (BLM), mimicking microbial cell membrane. Electrochemical impedance spectroscopy (EIS), high-resolution atomic force microscopy (AFM) imaging, and polarization-modulation infrared reflection-absorption spectroscopy (PM-IRRAS) were applied to study the peptide influence on a model microbial-like membrane. We show that LL-37 causes changes in the phospholipid molecules conformation and orientation, leading to membrane disintegration, significantly affecting the membrane electrical parameters, such as capacitance and resistance. High-resolution AFM imaging shows topographical and mechanical effects of such disintegration, while PM-IRRAS data indicates that introduction of LL-37 causes changes in the phospholipid acyl chains from all-trans to gauche conformations. Moreover, the presence of LL-37 significantly alters the value of the phospholipid tilt angle. Altogether, our results suggest a "carpet" membrane dissolution followed by a detergent-like membrane disruption mechanism upon LL-37 activity. This research gives a novel insight into the understanding of LL-37 influence on multicomponent model membranes and a promising contribution to the development of LL-37-derived therapeutic agents against drug-resistant bacteria.
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Affiliation(s)
- Marta Majewska
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
| | - Vlad Zamlynny
- Chemistry Department, Acadia University, 6 University Avenue, Wolfville, NS B4P 2R6, Canada
| | - Izabela S Pieta
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
| | - Robert Nowakowski
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
| | - Piotr Pieta
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland.
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Majewska M, Khan F, Pieta IS, Wróblewska A, Szmigielski R, Pieta P. Toxicity of selected airborne nitrophenols on eukaryotic cell membrane models. CHEMOSPHERE 2021; 266:128996. [PMID: 33288286 DOI: 10.1016/j.chemosphere.2020.128996] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 10/26/2020] [Accepted: 11/16/2020] [Indexed: 06/12/2023]
Abstract
Nitroaromatics belong to the group of toxic components of aerosol particles and atmospheric hydrometeors that enter the atmosphere through biomass burning and fuel combustion. In the present work, we report on the cytotoxic effects of a 2-, 3- and 4-nitrophenol mixture on a model eukaryotic-like cell membrane and compared it with in vitro cellular models BEAS-2B (immortalized bronchial epithelial cells) and A549 (cancerous alveolar epithelial cells). A selected model biomembrane comprised of DMPC (1,2-dimyristoyl-sn-glycero-3-phosphocholine), DPPC (1,2-dipalmitoyl-sn-glycero-3-phosphocholine) and POPC (1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine) was studied. The electrochemical-based method, combined with atomic force microscopy (AFM) and phase-contrast microscopy imaging, allowed to get insights into the mechanism of cellular function disruption caused by airborne nitrophenols. The efficacy of the method is supported by the data obtained from in vitro experiments performed on cell models. The nitrophenol mixture exhibited cytotoxic effects at concentrations above 100 μg mL-1, as demonstrated by phase-contrast microscopy in real lung cell lines. Electrochemical impedance spectroscopy (EIS) revealed the formation of membrane defects at a nitrophenol concentration of 200 μg mL-1. AFM imaging confirmed the model membrane disintegration and phospholipids rearrangement in the presence of nitrophenols. These observations indicate that particle-bound nitrophenols induce substantial changes in cell membranes and make them more permeable to aerosol, resulting in major cellular damage in the lungs when inhaled. The study provides initial evidence of cellular membrane damage induced by three important nitrated phenols present in the environment.
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Affiliation(s)
- Marta Majewska
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224, Warsaw, Poland
| | - Faria Khan
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224, Warsaw, Poland
| | - Izabela S Pieta
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224, Warsaw, Poland
| | - Aleksandra Wróblewska
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224, Warsaw, Poland
| | - Rafal Szmigielski
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224, Warsaw, Poland.
| | - Piotr Pieta
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224, Warsaw, Poland.
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Gabriunaite I, Valiūnienė A, Sabirovas T, Valincius G. Mixed Silane‐based Self‐assembled Monolayers Deposited on Fluorine Doped Tin Oxide as Model System for Development of Biosensors for Toxin Detection. ELECTROANAL 2021. [DOI: 10.1002/elan.202060578] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- Inga Gabriunaite
- Department of Physical Chemistry Faculty of Chemistry and Geosciences Vilnius University Naugarduko 24 Vilnius, LT 03225 Lithuania
| | - Aušra Valiūnienė
- Department of Physical Chemistry Faculty of Chemistry and Geosciences Vilnius University Naugarduko 24 Vilnius, LT 03225 Lithuania
| | - Tomas Sabirovas
- Institute of Biochemistry Life Sciences Centre Vilnius University Sauletekio ave. 7 Vilnius, LT 10257 Lithuania
| | - Gintaras Valincius
- Institute of Biochemistry Life Sciences Centre Vilnius University Sauletekio ave. 7 Vilnius, LT 10257 Lithuania
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Raila T, Ambrulevičius F, Penkauskas T, Jankunec M, Meškauskas T, Vanderah DJ, Valincius G. Clusters of protein pores in phospholipid bilayer membranes can be identified and characterized by electrochemical impedance spectroscopy. Electrochim Acta 2020. [DOI: 10.1016/j.electacta.2020.137179] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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Gabriunaite I, Valiūnienė A, Poderyte M, Ramanavicius A. Silane-based self-assembled monolayer deposited on fluorine doped tin oxide as model system for pharmaceutical and biomedical analysis. J Pharm Biomed Anal 2020; 177:112832. [PMID: 31473480 DOI: 10.1016/j.jpba.2019.112832] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Revised: 08/09/2019] [Accepted: 08/21/2019] [Indexed: 11/28/2022]
Abstract
Recently, self-assembled monolayers (SAMs) are gaining a lot of interest due to their simplicity of preparation and wide applicability in the development of model systems used in pharmaceutical and biomedical analysis. The most efficient methods used for the investigation of SAM-based structures usually include cyclic voltammetry and electrochemical impedance spectroscopy. Scanning electrochemical microscopy (SECM) could be also used as an alternative method for SAM investigations, because this method enables to map modified surface. In this work, the surface of fluorine doped tin oxide (FTO) was modified with octadeciltrichlorosilane (OTS) based SAM and investigated using SECM. Measurements, which were carried out by SECM, lead to conclusion that highly heterogeneous and distributed monolayer has been formed on FTO surface.
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Affiliation(s)
- Inga Gabriunaite
- Department of Physical Chemistry, Faculty of Chemistry and Geosciences, Vilnius University, Naugarduko str. 24, LT- 03225 Vilnius, Lithuania
| | - Aušra Valiūnienė
- Department of Physical Chemistry, Faculty of Chemistry and Geosciences, Vilnius University, Naugarduko str. 24, LT- 03225 Vilnius, Lithuania
| | - Margarita Poderyte
- Department of Physical Chemistry, Faculty of Chemistry and Geosciences, Vilnius University, Naugarduko str. 24, LT- 03225 Vilnius, Lithuania
| | - Arunas Ramanavicius
- Department of Physical Chemistry, Faculty of Chemistry and Geosciences, Vilnius University, Naugarduko str. 24, LT- 03225 Vilnius, Lithuania; Laboratory of Nanotechnology, State Research Institute Centre of Physical Sciences and Technology, Sauletekio Ave 3, LT-10257 Vilnius, Lithuania.
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Chen R, Huang H, Liu H, Xi J, Ning J, Zeng W, Shen C, Zhang T, Yu G, Xu Q, Chen X, Wang J, Lu F. Friend or Foe? Evidence Indicates Endogenous Exosomes Can Deliver Functional gRNA and Cas9 Protein. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2019; 15:e1902686. [PMID: 31271518 DOI: 10.1002/smll.201902686] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Indexed: 06/09/2023]
Abstract
The clustered regularly interspaced short palindromic repeats (CRISPR)/associated nuclease (Cas) system is an efficient gene editing tool. In this study, it is found that both single guide RNA (gRNA) and Cas9 protein could be exported from the CRISPR/Cas9-expressing cells by endogenous exosomes independently. Further experiments demonstrate that these naturally produced endogenous exosomes could be used as a vehicle to deliver the functional Cas9 and hepatitis B virus (HBV)-specific gRNA to cut HBV DNA transfected in HuH7 cells or human papilloma virus (HPV)-specific gRNA to cut the integrated HPV DNA in HeLa cells, respectively. In conclusion, this study indicates the potential of endogenous exosomes as a safe and effective delivery vehicle of the functional gRNA and Cas9 protein. Meanwhile, the endogenous exosomes-mediated delivery of gene editing activity to adjacent and distant cells or tissues may further complicate the off-target and safety concerns about the CRISPR/Cas9 system.
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Affiliation(s)
- Ran Chen
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Microbiology & Infectious Disease Center, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, 100191, China
| | - Hongxin Huang
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Microbiology & Infectious Disease Center, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, 100191, China
| | - Hui Liu
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Microbiology & Infectious Disease Center, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, 100191, China
| | - Jingyuan Xi
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Microbiology & Infectious Disease Center, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, 100191, China
| | - Jing Ning
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Microbiology & Infectious Disease Center, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, 100191, China
| | - Wanjia Zeng
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Microbiology & Infectious Disease Center, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, 100191, China
| | - Congle Shen
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Microbiology & Infectious Disease Center, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, 100191, China
| | - Ting Zhang
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Microbiology & Infectious Disease Center, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, 100191, China
| | - Guangxin Yu
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Microbiology & Infectious Disease Center, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, 100191, China
| | - Qiang Xu
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Microbiology & Infectious Disease Center, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, 100191, China
| | - Xiangmei Chen
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Microbiology & Infectious Disease Center, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, 100191, China
| | - Jie Wang
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Microbiology & Infectious Disease Center, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, 100191, China
| | - Fengmin Lu
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Microbiology & Infectious Disease Center, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, 100191, China
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Electrochemical impedance of randomly distributed defects in tethered phospholipid bilayers: Finite element analysis. Electrochim Acta 2019. [DOI: 10.1016/j.electacta.2018.12.148] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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Gabriunaite I, Valiūnienė A, Valincius G. Formation and properties of phospholipid bilayers on fluorine doped tin oxide electrodes. Electrochim Acta 2018. [DOI: 10.1016/j.electacta.2018.04.160] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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Karageorgos I, Silin VI, Zvonok N, Marino J, Janero DR, Makriyannis A. The role of human monoacylglycerol lipase (hMAGL) binding pocket in breakup of unsaturated phospholipid membranes. Anal Biochem 2017; 536:90-95. [PMID: 28822686 DOI: 10.1016/j.ab.2017.08.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Revised: 07/24/2017] [Accepted: 08/14/2017] [Indexed: 11/18/2022]
Abstract
Human monoacylglycerol lipase (hMAGL) plays a key role in homeostatic tuning of the endocannabinoid signaling system and supports aggressive tumorogenesis, making this enzyme a promising therapeutic target. hMAGL features a membrane-associated lid domain that regulates entry of endocannabinoid lipid substrates into the hydrophobic channel accessing the active site, likely from the membrane bilayer. The present work applied simultaneous surface plasmon resonance and electrochemical impedance spectroscopy measurements to show that, in absence of the substrate, hMAGL can remove phospholipid molecules from the membrane and, thereby, disintegrate pre-formed, intact, tethered phospholipid bilayer membrane mimetics (tBLMs) composed of unsaturated phosphatidylcholines. To probe the mechanism of hMAGL-induced on tBLMs compromise, we investigated the effect of wild type and mutant hMAGLs and hMAGL rendered catalytically inactive, as a function of concentration and in the presence of chemically distinct active-site inhibitors. Our data show that hMAGL's lid domain and hydrophobic substrate-binding pocket play important roles in hMAGL-induced bilayer lipid mobilization, whereas hydrolytic activity of the enzyme does not appear to be a factor.
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Affiliation(s)
- Ioannis Karageorgos
- Biomolecular Measurement Division, National Institute of Standards and Technology, Gaithersburg, MD, 20899, United States; Institute for Bioscience and Biotechnology Research, Rockville, MD, 20850, United States.
| | - Vitalii I Silin
- Institute for Bioscience and Biotechnology Research, Rockville, MD, 20850, United States
| | - Nikolai Zvonok
- Center for Drug Discovery, Northeastern University, Boston, MA, 02115, United States; Department of Chemistry and Chemical Biology, Northeastern University, Boston, MA, 02115, United States; Pharmaceutical Sciences Department, Northeastern University, Boston, MA, 02115, United States
| | - John Marino
- Biomolecular Measurement Division, National Institute of Standards and Technology, Gaithersburg, MD, 20899, United States; Institute for Bioscience and Biotechnology Research, Rockville, MD, 20850, United States
| | - David R Janero
- Center for Drug Discovery, Northeastern University, Boston, MA, 02115, United States; Department of Chemistry and Chemical Biology, Northeastern University, Boston, MA, 02115, United States; Pharmaceutical Sciences Department, Northeastern University, Boston, MA, 02115, United States
| | - Alexandros Makriyannis
- Center for Drug Discovery, Northeastern University, Boston, MA, 02115, United States; Department of Chemistry and Chemical Biology, Northeastern University, Boston, MA, 02115, United States; Pharmaceutical Sciences Department, Northeastern University, Boston, MA, 02115, United States
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Divya KP, Dharuman V. Supported binary liposome vesicle-gold nanoparticle for enhanced label free DNA and protein sensing. Biosens Bioelectron 2017; 95:168-173. [DOI: 10.1016/j.bios.2017.04.022] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Revised: 04/11/2017] [Accepted: 04/18/2017] [Indexed: 01/05/2023]
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12
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Durrani-Kolarik S, Pool CA, Gray A, Heyob KM, Cismowski MJ, Pryhuber G, Lee LJ, Yang Z, Tipple TE, Rogers LK. miR-29b supplementation decreases expression of matrix proteins and improves alveolarization in mice exposed to maternal inflammation and neonatal hyperoxia. Am J Physiol Lung Cell Mol Physiol 2017; 313:L339-L349. [PMID: 28473324 PMCID: PMC5582933 DOI: 10.1152/ajplung.00273.2016] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Revised: 04/28/2017] [Accepted: 04/30/2017] [Indexed: 02/06/2023] Open
Abstract
Even with advances in the care of preterm infants, chronic lung disease or bronchopulmonary dysplasia (BPD) continues to be a significant pulmonary complication. Among those diagnosed with BPD, a subset of infants develop severe BPD with disproportionate pulmonary morbidities. In addition to decreased alveolarization, these infants develop obstructive and/or restrictive lung function due to increases in or dysregulation of extracellular matrix proteins. Analyses of plasma obtained from preterm infants during the first week of life indicate that circulating miR-29b is suppressed in infants that subsequently develop BPD and that decreased circulating miR-29b is inversely correlated with BPD severity. Our mouse model mimics the pathophysiology observed in infants with severe BPD, and we have previously reported decreased pulmonary miR-29b expression in this model. The current studies tested the hypothesis that adeno-associated 9 (AAV9)-mediated restoration of miR-29b in the developing lung will improve lung alveolarization and minimize the deleterious changes in matrix deposition. Pregnant C3H/HeN mice received an intraperitoneal LPS injection on embryonic day 16 and newborn pups were exposed to 85% oxygen from birth to 14 days of life. On postnatal day 3, AAV9-miR-29b or AAV9-control was administered intranasally. Mouse lung tissues were then analyzed for changes in miR-29 expression, alveolarization, and matrix protein levels and localization. Although only modest improvements in alveolarization were detected in the AAV9-miR29b-treated mice at postnatal day 28, treatment completely attenuated defects in matrix protein expression and localization. Our data suggest that miR-29b restoration may be one component of a novel therapeutic strategy to treat or prevent severe BPD in prematurely born infants.
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Affiliation(s)
- Shaheen Durrani-Kolarik
- Center for Perinatal Research, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio
- Department of Pediatrics, The Ohio State University, Columbus, Ohio
| | - Caylie A Pool
- Center for Perinatal Research, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio
| | - Ashley Gray
- Center for Perinatal Research, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio
| | - Kathryn M Heyob
- Center for Perinatal Research, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio
| | - Mary J Cismowski
- Center for Cardiovascular Research, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio
- Department of Pediatrics, The Ohio State University, Columbus, Ohio
| | - Gloria Pryhuber
- Department of Pediatrics, University of Rochester Medical Center, Rochester, New York
| | - L James Lee
- The Center for Affordable Nanoengineering of Polymeric Biomedical Devices, The Ohio State University, Columbus, Ohio
| | - Zhaogang Yang
- The Center for Affordable Nanoengineering of Polymeric Biomedical Devices, The Ohio State University, Columbus, Ohio
| | - Trent E Tipple
- Division of Neonatology, Department of Pediatrics, University of Alabama at Birmingham, Birmingham, Alabama; and
| | - Lynette K Rogers
- Center for Perinatal Research, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio;
- Department of Pediatrics, The Ohio State University, Columbus, Ohio
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Andersson J, Knobloch JJ, Perkins MV, Holt SA, Köper I. Synthesis and Characterization of Novel Anchorlipids for Tethered Bilayer Lipid Membranes. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2017; 33:4444-4451. [PMID: 28387116 DOI: 10.1021/acs.langmuir.7b00778] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Tethered bilayer lipid membranes are versatile solid-supported model membrane systems. Core to these systems is an anchorlipid that covalently links a lipid bilayer to a support. The molecular structure of these lipids can have a significant impact on the properties of the resulting bilayer. Here, the synthesis of anchorlipids containing ester groups in the tethering part is described. The lipids are used to form bilayer membranes, and the resulting structures are compared with membranes formed using conventional anchorlipids or sparsely tethered membranes. All membranes showed good electrical sealing properties; the disulphide-terminated anchorlipids could be used in a sparsely tethered system without significantly reducing the sealing properties of the lipid bilayers. The sparsely tethered systems also allowed for higher ion transport across the membrane, which is in good correlation with higher hydration of the spacer region as seen by neutron scattering.
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Affiliation(s)
- Jakob Andersson
- Flinders Centre for Nanoscalce Science and Technology and School of Chemical and Physical Sciences, Flinders University , Adelaide 5042, Australia
| | - Jacqueline J Knobloch
- Flinders Centre for Nanoscalce Science and Technology and School of Chemical and Physical Sciences, Flinders University , Adelaide 5042, Australia
| | - Michael V Perkins
- Flinders Centre for Nanoscalce Science and Technology and School of Chemical and Physical Sciences, Flinders University , Adelaide 5042, Australia
| | - Stephen A Holt
- Australian Centre for Neutron Scattering, Australian Nuclear Science and Technology Organisation , Locked Bag 2001, Kirrawee DC, New South Wales 2234, Australia
| | - Ingo Köper
- Flinders Centre for Nanoscalce Science and Technology and School of Chemical and Physical Sciences, Flinders University , Adelaide 5042, Australia
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Ragaliauskas T, Mickevicius M, Rakovska B, Penkauskas T, Vanderah DJ, Heinrich F, Valincius G. Fast formation of low-defect-density tethered bilayers by fusion of multilamellar vesicles. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2017; 1859:669-678. [PMID: 28088448 DOI: 10.1016/j.bbamem.2017.01.015] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2016] [Revised: 12/19/2016] [Accepted: 01/10/2017] [Indexed: 10/20/2022]
Abstract
A facile and reproducible preparation of surface-supported lipid bilayers is essential for fundamental membrane research and biotechnological applications. We demonstrate that multilamellar vesicles fuse to molecular-anchor-grafted surfaces yielding low-defect-density, tethered bilayer membranes. Continuous bilayers are formed within 10min, while the electrically insulating bilayers with <0.1μm-2 defect density can be accomplished within 60min. Surface plasmon resonance spectroscopy indicates that an amount of lipid material transferred from vesicles to a surface is inversely proportional to the density of an anchor, while the total amount of lipid that includes tethered and transferred lipid remains constant within 5% standard error. This attests for the formation of intact bilayers independent of the tethering agent density. Neutron reflectometry (NR) revealed the atomic level structural details of the tethered bilayer showing, among other things, that the total thickness of the hydrophobic slab of the construct was 3.2nm and that the molar fraction of cholesterol in lipid content is essentially the same as the molar fraction of cholesterol in the multilamellar liposomes. NR also indicated the formation of an overlayer with an effective thickness of 1.9nm. These overlayers may be easily removed by a single rinse of the tethered construct with 30% ethanol solution. Fast assembly and low residual defect density achievable within an hour of fusion makes our tethered bilayer methodology an attractive platform for biosensing of membrane damaging agents, such as pore forming toxins.
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Affiliation(s)
- Tadas Ragaliauskas
- Institute of Biochemistry, Vilnius University, Sauletekio 7, Vilnius LT-10257 , Lithuania
| | - Mindaugas Mickevicius
- Institute of Biochemistry, Vilnius University, Sauletekio 7, Vilnius LT-10257 , Lithuania
| | - Bozena Rakovska
- Institute of Biochemistry, Vilnius University, Sauletekio 7, Vilnius LT-10257 , Lithuania
| | - Tadas Penkauskas
- Institute of Biochemistry, Vilnius University, Sauletekio 7, Vilnius LT-10257 , Lithuania
| | - David J Vanderah
- Institute for Bioscience and Biotechnology Research, Rockville, MD 20850, USA
| | - Frank Heinrich
- Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA; Department of Physics, Carnegie Mellon University, Pittsburgh, PA 15213, USA
| | - Gintaras Valincius
- Institute of Biochemistry, Vilnius University, Sauletekio 7, Vilnius LT-10257 , Lithuania.
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Valiūnienė A, Petrulionienė T, Balevičiūtė I, Mikoliūnaitė L, Valinčius G. Formation of hybrid bilayers on silanized thin-film Ti electrode. Chem Phys Lipids 2016; 202:62-68. [PMID: 27964891 DOI: 10.1016/j.chemphyslip.2016.12.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Revised: 12/01/2016] [Accepted: 12/05/2016] [Indexed: 11/29/2022]
Abstract
Phospholipid bilayer membranes are essential elements of living organisms as they form boundaries between the intracellular cytoplasm and the extracellular environment, as well as organelles. In this work we report on our attempts to assemble artificial phospholipid bilayer model membranes on Ti surface. To provide hydrophobic cushion for phospholipids, the surface of a thin-film Ti electrode was initially functionalized with trichloro(octadecyl)silane (OTS). Increased hydrophobicity of the solid support allowed vesicle fusion and the formation of a hybrid 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) bilayer, as probed by the electrochemical impedance spectroscopy (EIS), contact angle measurements (CA) also by the Fourier transform-infrared (FT-IR) spectroscopy, spectroscopic ellipsometry (SE) and atomic force microscopy (AFM). Our study demonstrates the applicability of thin-film Ti electrodes for the formation of hybrid bilayer membranes. These membranes allow functional reconstitution of the pore-forming toxins and provide a bioanalytical platform for the detection of the activity of the cholesterol-dependent cytolysins.
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Affiliation(s)
- A Valiūnienė
- Department of Physical Chemistry, Faculty of Chemistry, Vilnius University, Naugarduko 24, Vilnius LT-03225, Lithuania.
| | - T Petrulionienė
- Department of Physical Chemistry, Faculty of Chemistry, Vilnius University, Naugarduko 24, Vilnius LT-03225, Lithuania
| | - I Balevičiūtė
- Department of Physical Chemistry, Faculty of Chemistry, Vilnius University, Naugarduko 24, Vilnius LT-03225, Lithuania
| | - L Mikoliūnaitė
- Department of Physical Chemistry, Faculty of Chemistry, Vilnius University, Naugarduko 24, Vilnius LT-03225, Lithuania
| | - G Valinčius
- Department of Chemistry and Bioengineering, Vilnius Gedimino Technical University, Sauletekio al. 11, LT-10223, Vilnius, Lithuania
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16
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Valincius G, Mickevicius M, Penkauskas T, Jankunec M. Electrochemical Impedance Spectroscopy of Tethered Bilayer Membranes: An Effect of Heterogeneous Distribution of Defects in Membranes. Electrochim Acta 2016. [DOI: 10.1016/j.electacta.2016.11.056] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Finn ST, Macdonald JE. Contact and Support Considerations in the Hydrogen Evolution Reaction Activity of Petaled MoS2 Electrodes. ACS APPLIED MATERIALS & INTERFACES 2016; 8:25185-25192. [PMID: 27564136 DOI: 10.1021/acsami.6b05101] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Petaled MoS2 electrodes grown hydrothermally from Mo foils are found to have an 800 nm, intermediate, MoSxOy layer. Similar petaled MoS2 films without this intermediate layer are grown on Au. X-ray photoelectron and Raman spectroscopies and transmission electron microscopy indicate the resulting petaled multilayer MoS2 films are frayed and exhibit single-layer, 1T-MoS2 behavior at the edges. We compare the electrocatalytic hydrogen evolution reaction activity via linear sweep voltammetry with Tafel analysis as well as the impedance properties of the electrodes. We find that petaled MoS2/Au and petaled MoS2/Mo exhibit comparable overpotential to 10 mA cm(-2) at -279 vs -242 mV, respectively, and similar Tafel slopes of ∼68 mV/decade indicating a similar rate-determining step. The exchange current normalized to the geometric area of petaled MoS2/Au (0.000921 mA cm(-2)) is 3 times smaller than that of petaled MoS2/Mo (0.00290 mA cm(-2)), and is attributed to the lower petal density on the Au support. However, Au supports increase the turnover frequency per active site of petaled MoS2 to 0.48 H2 Mo(-1) s(-1) from 0.25 H2 Mo(-1) s(-1) on Mo supports. Both petaled MoS2 films have nearly ohmic contacts to their supports with uncompensated resistivity Ru of <2.5 Ω·cm(2).
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Affiliation(s)
- Shane T Finn
- Department of Chemistry and Vanderbilt Institute for Nanoscale Science and Engineering, Vanderbilt University , Nashville, Tennessee 37235, United States
| | - Janet E Macdonald
- Department of Chemistry and Vanderbilt Institute for Nanoscale Science and Engineering, Vanderbilt University , Nashville, Tennessee 37235, United States
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Abstract
RATIONALE Bronchopulmonary dysplasia remains a significant cause of neonatal morbidity; however, the identification of novel targets to predict or prevent the development of bronchopulmonary dysplasia remains elusive. Proper microRNA (miR)-17∼92 cluster is necessary for normal lung development, and alterations in expression are reported in other pulmonary diseases. The overall hypothesis for our work is that altered miR-17∼92 cluster expression contributes to the molecular pathogenesis of bronchopulmonary dysplasia. OBJECTIVES The current studies tested the hypothesis that alterations in miR-17∼92 cluster and DNA methyltransferase expression are present in bronchopulmonary dysplasia. METHODS miR-17∼92 cluster expression, promoter methylation, and DNA methyltransferase expression were determined in autopsy lung samples obtained from premature infants who died with bronchopulmonary dysplasia, or from term/near-term infants who died from nonrespiratory causes. Expression of miR-17∼92 cluster members miR-17 and -19b was measured in plasma samples collected in the first week of life from a separate cohort of preterm infants at a second institution in whom bronchopulmonary dysplasia was diagnosed subsequently. MEASUREMENTS AND MAIN RESULTS Autopsy tissue data indicated that miR-17∼92 expression is significantly lower in bronchopulmonary dysplasia lungs and is inversely correlated with promoter methylation and DNA methyltransferase expression when compared with that of control subjects without bronchopulmonary dysplasia. Plasma sample analyses indicated that miR-17 and -19b expression was decreased in infants who subsequently developed bronchopulmonary dysplasia. CONCLUSIONS Our data are the first to demonstrate altered expression of the miR-17∼92 cluster in bronchopulmonary dysplasia. The consistency between our autopsy and plasma findings further support our working hypothesis that the miR-17∼92 cluster contributes to the molecular pathogenesis of bronchopulmonary dysplasia.
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Zieleniecki JL, Nagarajan Y, Waters S, Rongala J, Thompson V, Hrmova M, Köper I. Cell-Free Synthesis of a Functional Membrane Transporter into a Tethered Bilayer Lipid Membrane. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2016; 32:2445-2449. [PMID: 26910192 DOI: 10.1021/acs.langmuir.5b04059] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Eukaryotic cell-free synthesis was used to incorporate the large and complex multispan plant membrane transporter Bot1 in a functional form into a tethered bilayer lipid membrane. The electrical properties of the protein-functionalized tethered bilayer were measured using electrochemical impedance spectroscopy and revealed a pH-dependent transport of borate ions through the protein. The efficacy of the protein synthesis has been evaluated using immunoblot analysis.
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Affiliation(s)
- Julius L Zieleniecki
- Flinders Centre for Nanoscale Science and Technology School of Chemical and Physical Sciences, Flinders University , Bedford Park, South Australia 5042, Australia
| | - Yagnesh Nagarajan
- Australian Centre for Plant Functional Genomics School of Agriculture, Food, and Wine, University of Adelaide , Glen Osmond, South Australia 5064, Australia
| | - Shane Waters
- Australian Centre for Plant Functional Genomics School of Agriculture, Food, and Wine, University of Adelaide , Glen Osmond, South Australia 5064, Australia
| | - Jay Rongala
- Australian Centre for Plant Functional Genomics School of Agriculture, Food, and Wine, University of Adelaide , Glen Osmond, South Australia 5064, Australia
| | - Vanessa Thompson
- Flinders Centre for Nanoscale Science and Technology School of Chemical and Physical Sciences, Flinders University , Bedford Park, South Australia 5042, Australia
| | - Maria Hrmova
- Australian Centre for Plant Functional Genomics School of Agriculture, Food, and Wine, University of Adelaide , Glen Osmond, South Australia 5064, Australia
| | - Ingo Köper
- Flinders Centre for Nanoscale Science and Technology School of Chemical and Physical Sciences, Flinders University , Bedford Park, South Australia 5042, Australia
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20
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Bhuvana M, Dharuman V. Tethering of spherical DOTAP liposome gold nanoparticles on cysteamine monolayer for sensitive label free electrochemical detection of DNA and transfection. Analyst 2015; 139:2467-75. [PMID: 24652193 DOI: 10.1039/c4an00017j] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Construction of spherical liposomes is critical for developing tools for targeted gene and drug delivery applications in biotechnology and medicine, however, it has been demonstrated only in solution phase until now. Spherical liposome tethering on pristine thiol monolayer on gold transducer and its application to label free DNA sensing and transfection has rarely been reported. Here, we report tethering of spherical 1,2-dioleoyltrimethylammoniumpropane liposome-gold nanoparticle (DOTAP-AuNP) on amine terminated monolayer by simple electrostatic interaction on gold transducer for the first time. Cuddling of cationic liposome by AuNP prevents spherical vesicle fusion in both liquid and solid phases, an essential criterion required for gene and drug delivery applications. The spherical nature of DOTAP-AuNPs on a gold surface is confirmed electrochemically using both [Fe(CN)6](3-/4-) and [Ru(NH3)6](3+) redox probes. Atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), dynamic light scattering (DLS) and ultraviolet-visible (UV) spectroscopic techniques confirm the robust nature of spherical liposome-AuNPs on solid and in liquid phases. The surface is applied for label free DNA hybridization and single nucleotide polymorphism detections sensitively and selectively without signal amplification. The lowest target DNA concentration detected is 100 attomole. DNA transfection is made simply by dropping E. coli cells on DOTAP-AuNP-DNA immobilized transducer surface. The difference between the fluorescent image of transfected E. coli and the differential interference contrast image of E. coli cells by confocal laser scanning microscopy (CLSM) confirms the efficiency and simplicity of the transfection method developed in terms of reduced cost and reagents.
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Affiliation(s)
- Mohanlal Bhuvana
- Molecular Electronics Laboratory, Department of Bioelectronics and Biosensors, Science Block, Alagappa University, Karaikudi, 630 004, India.
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21
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Rakovska B, Ragaliauskas T, Mickevicius M, Jankunec M, Niaura G, Vanderah DJ, Valincius G. Structure and function of the membrane anchoring self-assembled monolayers. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2015; 31:846-857. [PMID: 25525904 DOI: 10.1021/la503715b] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Structure of the self-assembled monolayers (SAMs) used to anchor phospholipid bilayers to surfaces affects the functional properties of the tethered bilayer membranes (tBLMs). SAMs of the same surface composition differing in the lateral distribution of the anchor molecule give rise to tBLMs of profoundly different defectiveness with residual conductance spanning 3 orders of magnitude. SAMs composed of anchors containing saturated alkyl chains, upon exposure to water (72 h), reconstruct to tightly packed clusters as deduced from reflection absorption infrared spectroscopy data and directly visualized by atomic force microscopy. The rearrangement into clusters results in an inability to establish highly insulating tBLMs on the same anchor layer. Unexpectedly, we also found that nanometer scale smooth gold film surfaces, populated predominantly with (111) facets, exhibit poor performance from the standpoint of the defectiveness of the anchored phospholipid bilayers, while corrugated (110) dominant surfaces produced SAMs with superior tethering quality. Although the detailed mechanism of cluster formation remains to be clarified, it appears that smooth surfaces favor lateral translocation of the molecular anchors, resulting in changes in functional properties of the SAMs. This work unequivocally establishes that conditions that favor cluster formation of the anchoring molecules in tBLM formation must be identified and avoided for the functional use of tBLMs in biomedical and diagnostic applications.
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Affiliation(s)
- Bozena Rakovska
- Institute of Biochemistry, Vilnius University , Mokslininku 12, Vilnius 08662, Lithuania
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22
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Valincius G, Mickevicius M. Tethered Phospholipid Bilayer Membranes. ADVANCES IN PLANAR LIPID BILAYERS AND LIPOSOMES 2015. [DOI: 10.1016/bs.adplan.2015.01.003] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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23
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Heinrich F, Lösche M. Zooming in on disordered systems: neutron reflection studies of proteins associated with fluid membranes. BIOCHIMICA ET BIOPHYSICA ACTA 2014; 1838:2341-9. [PMID: 24674984 PMCID: PMC4082750 DOI: 10.1016/j.bbamem.2014.03.007] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/24/2013] [Revised: 03/13/2014] [Accepted: 03/17/2014] [Indexed: 11/23/2022]
Abstract
Neutron reflectometry (NR) is an emerging experimental technique for the structural characterization of proteins interacting with fluid bilayer membranes under conditions that mimic closely the cellular environment. Thus, cellular processes can be emulated in artificial systems and their molecular basis studied by adding cellular components one at a time in a well-controlled environment while the resulting structures, or structural changes in response to external cues, are monitored with neutron reflection. In recent years, sample environments, data collection strategies and data analysis were continuously refined. The combination of these improvements increases the information which can be obtained from NR to an extent that enables structural characterization of protein-membrane complexes at a length scale that exceeds the resolution of the measurement by far. Ultimately, the combination of NR with molecular dynamics (MD) simulations can be used to cross-validate the results of the two techniques and provide atomic-scale structural models. This review discusses these developments in detail and demonstrates how they provide new windows into relevant biomedical problems. This article is part of a Special Issue entitled: Interfacially Active Peptides and Proteins. Guest Editors: William C. Wimley and Kalina Hristova.
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Affiliation(s)
- Frank Heinrich
- Physics Department, Carnegie Mellon University, Pittsburgh, PA, U.S.A.; NIST Center for Neutron Research, Gaithersburg, MD, U.S.A
| | - Mathias Lösche
- Physics Department, Carnegie Mellon University, Pittsburgh, PA, U.S.A.; NIST Center for Neutron Research, Gaithersburg, MD, U.S.A..
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24
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Shankara Narayanan J, Bhuvana M, Dharuman V. Sandwiching spherical 1,2-dioleoyltrimethylammoniumpropane liposome in gold nanoparticle on solid transducer for electrochemical ultrasensitive DNA detection and transfection. Biosens Bioelectron 2014; 58:326-32. [DOI: 10.1016/j.bios.2014.02.033] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2013] [Revised: 01/30/2014] [Accepted: 02/14/2014] [Indexed: 12/17/2022]
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25
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Bhuvana M, Dharuman V. Construction of spherical liposome on solid transducers for electrochemical DNA sensing and transfection. Appl Biochem Biotechnol 2014; 174:1137-50. [PMID: 24903960 DOI: 10.1007/s12010-014-0992-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2014] [Accepted: 05/19/2014] [Indexed: 10/25/2022]
Abstract
Cationic 1,2-dioleoyl trimethyl ammonium propane (DOTAP) and neutral 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE) are anchored on cysteamine (cyst), mercaptopropionic acid (MPA) monolayer (thiol monolayers) modified on an individual gold transducer. DOTAP and DOPE are mixed with gold nanoparticle (AuNP) to form spherical liposome-AuNP. The electrochemical behaviors of the surface attached DOTAP-AuNP and DOPE-AuNP in presence of [Fe(CN)6](3-/4-) depend on the method of layer formation. Transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), atomic force microscopy (AFM), and ultraviolet (UV)-visible spectroscopic techniques are used to characterize the liposome-AuNP nanocomposite. The studies indicate stability of spherical liposome-AuNP on the gold transducer. Label-free DNA hybridization detection on these surfaces reveals different detection limits. Confocal laser scanning microscopy (CLSM) is used to confirm the cell transfection.
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Affiliation(s)
- Mohanlal Bhuvana
- Molecular Electronics Laboratory, Department of Bioelectronics and Biosensors, Alagappa University, Karaikudi, 630 003, India
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26
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Wang S, Larson RG. Water channel formation and ion transport in linear and branched lipid bilayers. Phys Chem Chem Phys 2014; 16:7251-62. [DOI: 10.1039/c3cp55116d] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The lipid bilayer stability and water channel morphologies are affected by the presence of methyl branches on lipid tails.
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Affiliation(s)
- Shihu Wang
- Department of Chemical Engineering
- University of Michigan
- Ann Arbor, USA
| | - Ronald G. Larson
- Department of Chemical Engineering
- University of Michigan
- Ann Arbor, USA
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27
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Wu Y, Kwak KJ, Agarwal K, Marras A, Wang C, Mao Y, Huang X, Ma J, Yu B, Lee R, Vachani A, Marcucci G, Byrd JC, Muthusamy N, Otterson G, Huang K, Castro CE, Paulaitis M, Nana-Sinkam SP, Lee LJ. Detection of extracellular RNAs in cancer and viral infection via tethered cationic lipoplex nanoparticles containing molecular beacons. Anal Chem 2013; 85:11265-74. [PMID: 24102152 DOI: 10.1021/ac401983w] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Noninvasive early detection methods have the potential to reduce mortality rates of both cancer and infectious diseases. Here, we present a novel assay by which tethered cationic lipoplex nanoparticles containing molecular beacons (MBs) can capture cancer cell-derived exosomes or viruses and identify encapsulated RNAs in a single step. A series of ultracentrifugation and Exoquick isolation kit were first used to isolate exosomes from the cell culture medium and human serum, respectively. Cationic lipoplex nanoparticles linked onto the surface of a thin glass plate capture negatively charged viruses or cell-secreted exosomes by electrostatic interactions to form larger nanoscale complexes. Lipoplex/virus or lipoplex/exosome fusion leads to the mixing of viral/exosomal RNAs and MBs within the lipoplexes. After the target RNAs specially bind to the MBs, exosomes enriched in target RNAs are readily identified by the fluorescence signals of MBs. The in situ detection of target extracellular RNAs without diluting the samples leads to high detection sensitivity not achievable by existing methods, e.g., quantitative reverse transcription-polymerase chain reaction (qRT-PCR). Here we demonstrate this concept using lentivirus and serum from lung cancer patients.
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Affiliation(s)
- Yun Wu
- Center for Affordable Nanoengineering of Polymeric Biomedical Devices, The Ohio State University , 174 West 18th Avenue, Room 1012, Columbus, Ohio 43212, United States
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28
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Liu Y, Zhang Z, Zhang Q, Baker GL, Worden RM. Biomembrane disruption by silica-core nanoparticles: effect of surface functional group measured using a tethered bilayer lipid membrane. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2013; 1838:429-37. [PMID: 24060565 DOI: 10.1016/j.bbamem.2013.09.007] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2013] [Revised: 09/10/2013] [Accepted: 09/12/2013] [Indexed: 01/01/2023]
Abstract
Engineered nanomaterials (ENM) have desirable properties that make them well suited for many commercial applications. However, a limited understanding of how ENM's properties influence their molecular interactions with biomembranes hampers efforts to design ENM that are both safe and effective. This paper describes the use of a tethered bilayer lipid membrane (tBLM) to characterize biomembrane disruption by functionalized silica-core nanoparticles. Electrochemical impedance spectroscopy was used to measure the time trajectory of tBLM resistance following nanoparticle exposure. Statistical analysis of parameters from an exponential resistance decay model was then used to quantify and analyze differences between the impedance profiles of nanoparticles that were unfunctionalized, amine-functionalized, or carboxyl-functionalized. All of the nanoparticles triggered a decrease in membrane resistance, indicating nanoparticle-induced disruption of the tBLM. Hierarchical clustering allowed the potency of nanoparticles for reducing tBLM resistance to be ranked in the order amine>carboxyl~bare silica. Dynamic light scattering analysis revealed that tBLM exposure triggered minor coalescence for bare and amine-functionalized silica nanoparticles but not for carboxyl-functionalized silica nanoparticles. These results indicate that the tBLM method can reproducibly characterize ENM-induced biomembrane disruption and can distinguish the BLM-disruption patterns of nanoparticles that are identical except for their surface functional groups. The method provides insight into mechanisms of molecular interaction involving biomembranes and is suitable for miniaturization and automation for high-throughput applications to help assess the health risk of nanomaterial exposure or identify ENM having a desired mode of interaction with biomembranes.
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Affiliation(s)
- Ying Liu
- Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, MI 48824, USA
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29
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Budvytyte R, Valincius G, Niaura G, Voiciuk V, Mickevicius M, Stauffer H, Goh HZ, Shekhar P, Heinrich F, Shenoy S, Lösche M, Vanderah DJ. Structure and properties of tethered bilayer lipid membranes with unsaturated anchor molecules. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2013; 29:8645-56. [PMID: 23745652 PMCID: PMC3753044 DOI: 10.1021/la401132c] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
The self-assembled monolayers (SAMs) of new lipidic anchor molecule HC18 [Z-20-(Z-octadec-9-enyloxy)-3,6,9,12,15,18,22-heptaoxatetracont-31-ene-1-thiol] and mixed HC18/β-mercaptoethanol (βME) SAMs were studied by spectroscopic ellipsometry, contact angle measurements, reflection-absorption infrared spectroscopy, and electrochemical impedance spectroscopy (EIS) and were evaluated in tethered bilayer lipid membranes (tBLMs). Our data indicate that HC18, containing a double bond in the alkyl segments, forms highly disordered SAMs up to anchor/βME molar fraction ratios of 80/20 and result in tBLMs that exhibit higher lipid diffusion coefficients relative to those of previous anchor compounds with saturated alkyl chains, as determined by fluorescence correlation spectroscopy. EIS data shows the HC18 tBLMs, completed by rapid solvent exchange or vesicle fusion, form more easily than with saturated lipidic anchors, exhibit excellent electrical insulating properties indicating low defect densities, and readily incorporate the pore-forming toxin α-hemolysin. Neutron reflectivity measurements on HC18 tBLMs confirm the formation of complete tBLMs, even at low tether compositions and high ionic lipid compositions. Our data indicate that HC18 results in tBLMs with improved physical properties for the incorporation of integral membrane proteins (IMPs) and that 80% HC18 tBLMs appear to be optimal for practical applications such as biosensors where high electrical insulation and IMP/peptide reconstitution are imperative.
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Affiliation(s)
- Rima Budvytyte
- Institute of Biochemistry, Vilnius University, Vilnius, LT-08662, Lithuania
| | - Gintaras Valincius
- Institute of Biochemistry, Vilnius University, Vilnius, LT-08662, Lithuania
| | - Gediminas Niaura
- Institute of Biochemistry, Vilnius University, Vilnius, LT-08662, Lithuania
| | - Vladislava Voiciuk
- Institute of Biochemistry, Vilnius University, Vilnius, LT-08662, Lithuania
| | | | - Hilary Stauffer
- Material Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, MD 20899
- Hood College, Frederick, MD 21701
| | - Haw-Zan Goh
- Physics Department, Carnegie Mellon University, Pittsburgh, PA 15213
| | | | - Frank Heinrich
- Physics Department, Carnegie Mellon University, Pittsburgh, PA 15213
- Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD 20899
| | - Siddharth Shenoy
- Physics Department, Carnegie Mellon University, Pittsburgh, PA 15213
| | - Mathias Lösche
- Physics Department, Carnegie Mellon University, Pittsburgh, PA 15213
- Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD 20899
| | - David J. Vanderah
- Material Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, MD 20899
- Institute for Bioscience and Biotechnology Research, Rockville, MD 20850
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30
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Bhuvana M, Narayanan JS, Dharuman V, Teng W, Hahn JH, Jayakumar K. Gold surface supported spherical liposome-gold nano-particle nano-composite for label free DNA sensing. Biosens Bioelectron 2012; 41:802-8. [PMID: 23141707 DOI: 10.1016/j.bios.2012.10.017] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2012] [Revised: 09/26/2012] [Accepted: 10/04/2012] [Indexed: 10/27/2022]
Abstract
Immobilization of 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE) liposome-gold nano-particle (DOPE-AuNP) nano-composite covalently on 3-mercaptopropionic acid (MPA) on gold surface is demonstrated for the first time for electrochemical label free DNA sensing. Spherical nature of the DOPE on the MPA monolayer is confirmed by the appearance of sigmoidal voltammetric profile, characteristic behavior of linear diffusion, for the MPA-DOPE in presence of [Fe(CN)(6)](3-/4-) and [Ru(NH(3))(6)](3+) redox probes. The DOPE liposome vesicle fusion is prevented by electroless deposition of AuNP on the hydrophilic amine head groups of the DOPE. Immobilization of single stranded DNA (ssDNA) is made via simple gold-thiol linkage for DNA hybridization sensing in the presence of [Fe(CN)(6)](3-/4-). The sensor discriminates the hybridized (complementary target hybridized), un-hybridized (non-complementary target hybridized) and single base mismatch target hybridized surfaces sensitively and selectively without signal amplification. The lowest target DNA concentration detected is 0.1×10(-12)M. Cyclic voltammetry (CV), electrochemical impedance (EIS), differential pulse voltammetry (DPV) and quartz crystal microbalance (QCM) techniques are used for DNA sensing on DOPE-AuNP nano-composite. Transmission Electron Microscopy (TEM), Fourier Transform Infrared Spectroscopy (FTIR), Atomic Force Microscopy (AFM), Dynamic Light Scattering (DLS) and Ultraviolet-Visible (UV) spectroscopic techniques are used to understand the interactions between the DOPE, AuNP and ssDNA. The results indicate the presence of an intact and well defined spherical DOPE-AuNP nano-composite on the gold surface. The method could be applied for fabrication of the surface based liposome-AuNP-DNA composite for cell transfection studies at reduced reagents and costs.
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Affiliation(s)
- M Bhuvana
- Molecular Electronics Laboratory, Department of Bioelectronics and Biosensors, Alagappa University, Karaikudi 630003, India
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31
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Valincius G, Meškauskas T, Ivanauskas F. Electrochemical impedance spectroscopy of tethered bilayer membranes. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:977-90. [PMID: 22126190 DOI: 10.1021/la204054g] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The electrochemical impedance spectra (EIS) of tethered bilayer membranes (tBLMs) were analyzed, and the analytical solution for the spectral response of membranes containing natural or artificially introduced defects was derived. The analysis carried out in this work shows that the EIS features of an individual membrane defect cannot be modeled by conventional electrical elements. The primary reason for this is the complex nature of impedance of the submembrane ionic reservoir separating the phospholipid layer and the solid support. We demonstrate that its EIS response, in the case of radially symmetric defects, is described by the Hankel functions of a complex variable. Therefore, neither the impedance of the submembrane reservoir nor the total impedance of tBLMs can be modeled using the conventional elements of the equivalent electrical circuits of interfaces. There are, however, some limiting cases in which the complexity of the EIS response of the submembrane space reduces. In the high frequency limit, the EIS response of a submembrane space that surrounds the defect transforms into a response of a constant phase element (CPE) with the exponent (α) value of 0.5. The onset of this transformation is, beside other parameters, dependent on the defect size. Large-sized defects push the frequency limit lower, therefore, the EIS spectra exhibiting CPE behavior with α ≈ 0.5, can serve as a diagnostic criterion for the presence of such defects. In the low frequency limit, the response is dependent on the density of the defects, and it transforms into the capacitive impedance if the area occupied by a defect is finite. The higher the defect density, the higher the frequency edge at which the onset of the capacitive behavior is observed. Consequently, the presented analysis provides practical tools to evaluate the defect density in tBLMs, which could be utilized in tBLM-based biosensor applications. Alternatively, if the parameters of the defects, e.g., ion channels, such as the diameter and the conductance are known, the EIS data analysis provides a possibility to estimate other physical parameters of the system, such as thickness of the submembrane reservoir and its conductance. Finally, current analysis demonstrates a possibility to discriminate between the situations, in which the membrane defects are evenly distributed or clustered on the surface of tBLMs. Such sensitivity of EIS could be used for elucidation of the mechanisms of interaction between the proteins and the membranes.
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Affiliation(s)
- Gintaras Valincius
- Vilnius University Institute of Biochemistry, Mokslininku 12, LT-08662 Vilnius, Lithuania.
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