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Murastov G, Aslam MA, Leitner S, Tkachuk V, Plutnarová I, Pavlica E, Rodriguez RD, Sofer Z, Matković A. Multi-Layer Palladium Diselenide as a Contact Material for Two-Dimensional Tungsten Diselenide Field-Effect Transistors. Nanomaterials (Basel) 2024; 14:481. [PMID: 38470809 DOI: 10.3390/nano14050481] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2024] [Revised: 02/28/2024] [Accepted: 03/01/2024] [Indexed: 03/14/2024]
Abstract
Tungsten diselenide (WSe2) has emerged as a promising ambipolar semiconductor material for field-effect transistors (FETs) due to its unique electronic properties, including a sizeable band gap, high carrier mobility, and remarkable on-off ratio. However, engineering the contacts to WSe2 remains an issue, and high contact barriers prevent the utilization of the full performance in electronic applications. Furthermore, it could be possible to tune the contacts to WSe2 for effective electron or hole injection and consequently pin the threshold voltage to either conduction or valence band. This would be the way to achieve complementary metal-oxide-semiconductor devices without doping of the channel material.This study investigates the behaviour of two-dimensional WSe2 field-effect transistors with multi-layer palladium diselenide (PdSe2) as a contact material. We demonstrate that PdSe2 contacts favour hole injection while preserving the ambipolar nature of the channel material. This consequently yields high-performance p-type WSe2 devices with PdSe2 van der Waals contacts. Further, we explore the tunability of the contact interface by selective laser alteration of the WSe2 under the contacts, enabling pinning of the threshold voltage to the valence band of WSe2, yielding pure p-type operation of the devices.
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Affiliation(s)
- Gennadiy Murastov
- Department Physics, Mechanics and Electrical Engineering, Montanuniversität Leoben, Franz Josef Strasse 18, 8700 Leoben, Austria
| | - Muhammad Awais Aslam
- Department Physics, Mechanics and Electrical Engineering, Montanuniversität Leoben, Franz Josef Strasse 18, 8700 Leoben, Austria
| | - Simon Leitner
- Department Physics, Mechanics and Electrical Engineering, Montanuniversität Leoben, Franz Josef Strasse 18, 8700 Leoben, Austria
| | - Vadym Tkachuk
- Laboratory of Organic Matter Physics, University of Nova Gorica, Vipavska 13, SI-5000 Nova Gorica, Slovenia
| | - Iva Plutnarová
- Department of Inorganic Chemistry, University of Chemistry and Technology Prague, Technická 5, 166 28 Prague, Czech Republic
| | - Egon Pavlica
- Laboratory of Organic Matter Physics, University of Nova Gorica, Vipavska 13, SI-5000 Nova Gorica, Slovenia
| | - Raul D Rodriguez
- Research School of Chemistry & Applied Biomedical Sciences, Tomsk Polytechnic University, Lenina ave. 30, 634034 Tomsk, Russia
| | - Zdenek Sofer
- Department of Inorganic Chemistry, University of Chemistry and Technology Prague, Technická 5, 166 28 Prague, Czech Republic
| | - Aleksandar Matković
- Department Physics, Mechanics and Electrical Engineering, Montanuniversität Leoben, Franz Josef Strasse 18, 8700 Leoben, Austria
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2
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Hoffmann C, Murastov G, Tromm JV, Moog JB, Aslam MA, Matkovic A, Milovanovic D. Electric Potential at the Interface of Membraneless Organelles Gauged by Graphene. Nano Lett 2023; 23:10796-10801. [PMID: 37862690 PMCID: PMC10722609 DOI: 10.1021/acs.nanolett.3c02915] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Revised: 10/15/2023] [Indexed: 10/22/2023]
Abstract
Eukaryotic cells contain membrane-bound and membrane-less organelles that are often in contact with each other. How the interface properties of membrane-less organelles regulate their interactions with membranes remains challenging to assess. Here, we employ graphene-based sensors to investigate the electrostatic properties of synapsin 1, a major synaptic phosphoprotein, either in a single phase or after undergoing phase separation to form synapsin condensates. Using these graphene-based sensors, we discover that synapsin condensates generate strong electrical responses that are otherwise absent when synapsin is present as a single phase. By introducing atomically thin dielectric barriers, we show that the electrical response originates in an electric double layer whose formation governs the interaction between synapsin condensates and graphene. Our data indicate that the interface properties of the same protein are substantially different when the protein is in a single phase versus within a biomolecular condensate, unraveling that condensates can harbor ion potential differences at their interface.
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Affiliation(s)
- Christian Hoffmann
- Laboratory
of Molecular Neuroscience, German Center
for Neurodegenerative Diseases (DZNE), 10117 Berlin, Germany
| | - Gennadiy Murastov
- Chair
of Physics, Department Physics, Mechanics and Electrical Engineering, Montanuniversität Leoben, 8700 Leoben, Austria
| | - Johannes Vincent Tromm
- Laboratory
of Molecular Neuroscience, German Center
for Neurodegenerative Diseases (DZNE), 10117 Berlin, Germany
| | - Jean-Baptiste Moog
- Laboratory
of Molecular Neuroscience, German Center
for Neurodegenerative Diseases (DZNE), 10117 Berlin, Germany
| | - Muhammad Awais Aslam
- Chair
of Physics, Department Physics, Mechanics and Electrical Engineering, Montanuniversität Leoben, 8700 Leoben, Austria
| | - Aleksandar Matkovic
- Chair
of Physics, Department Physics, Mechanics and Electrical Engineering, Montanuniversität Leoben, 8700 Leoben, Austria
| | - Dragomir Milovanovic
- Laboratory
of Molecular Neuroscience, German Center
for Neurodegenerative Diseases (DZNE), 10117 Berlin, Germany
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3
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Coppola ME, Petritz A, Irimia CV, Yumusak C, Mayr F, Bednorz M, Matkovic A, Aslam MA, Saller K, Schwarzinger C, Ionita MD, Schiek M, Smeds AI, Salinas Y, Brüggemann O, D'Orsi R, Mattonai M, Ribechini E, Operamolla A, Teichert C, Xu C, Stadlober B, Sariciftci NS, Irimia‐Vladu M. Pinaceae Pine Resins (Black Pine, Shore Pine, Rosin, and Baltic Amber) as Natural Dielectrics for Low Operating Voltage, Hysteresis-Free, Organic Field Effect Transistors. Glob Chall 2023; 7:2300062. [PMID: 37745829 PMCID: PMC10517313 DOI: 10.1002/gch2.202300062] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 06/24/2023] [Indexed: 09/26/2023]
Abstract
Four pinaceae pine resins analyzed in this study: black pine, shore pine, Baltic amber, and rosin demonstrate excellent dielectric properties, outstanding film forming, and ease of processability from ethyl alcohol solutions. Their trap-free nature allows fabrication of virtually hysteresis-free organic field effect transistors operating in a low voltage window with excellent stability under bias stress. Such green constituents represent an excellent choice of materials for applications targeting biocompatibility and biodegradability of electronics and sensors, within the overall effort of sustainable electronics development and environmental friendliness.
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Affiliation(s)
| | - Andreas Petritz
- Joanneum Research ForschungsgesellschaftMaterialsFranz‐Pichler Str. Nr. 30Weiz8169Austria
| | - Cristian Vlad Irimia
- Joanneum Research ForschungsgesellschaftMaterialsFranz‐Pichler Str. Nr. 30Weiz8169Austria
- Johannes Kepler University LinzDept. Physical ChemistryLinz Institute for Organic Solar Cells (LIOS)Altenberger Str. Nr. 69Linz4040Austria
| | - Cigdem Yumusak
- Johannes Kepler University LinzDept. Physical ChemistryLinz Institute for Organic Solar Cells (LIOS)Altenberger Str. Nr. 69Linz4040Austria
| | - Felix Mayr
- Johannes Kepler University LinzDept. Physical ChemistryLinz Institute for Organic Solar Cells (LIOS)Altenberger Str. Nr. 69Linz4040Austria
| | - Mateusz Bednorz
- Johannes Kepler University LinzDept. Physical ChemistryLinz Institute for Organic Solar Cells (LIOS)Altenberger Str. Nr. 69Linz4040Austria
| | - Aleksandar Matkovic
- Chair of PhysicsDepartment of PhysicsMechanics and Electrical EngineeringMontanuniversität LeobenFranz Josef Str. 18Leoben8700Austria
| | - Muhammad Awais Aslam
- Chair of PhysicsDepartment of PhysicsMechanics and Electrical EngineeringMontanuniversität LeobenFranz Josef Str. 18Leoben8700Austria
| | - Klara Saller
- Institut for Chemical Technologies of Organic MaterialsJohannes Kepler University LinzAltenberger Str. Nr. 69Linz4040Austria
| | - Clemens Schwarzinger
- Institut for Chemical Technologies of Organic MaterialsJohannes Kepler University LinzAltenberger Str. Nr. 69Linz4040Austria
| | - Maria Daniela Ionita
- National Institute for LaserPlasma and Radiation PhysicsPO Box Mg‐36, MagureleBucharest077125Romania
| | - Manuela Schiek
- Johannes Kepler University LinzDept. Physical ChemistryLinz Institute for Organic Solar Cells (LIOS)Altenberger Str. Nr. 69Linz4040Austria
- Johannes Kepler University LinzCenter for Surface and Nanoanalytics (ZONA) Altenberger Str. 69Linz4040Austria
| | - Annika I. Smeds
- Laboratory of Natural Materials Technology/Wood and Paper ChemistryÅbo Akademi UniversityPorthansgatan 3‐5, ÅboTurku20500Finland
| | - Yolanda Salinas
- Institute of Polymer ChemistryJohannes Kepler University LinzAltenberger Str. 69Linz4040Austria
| | - Oliver Brüggemann
- Institute of Polymer ChemistryJohannes Kepler University LinzAltenberger Str. 69Linz4040Austria
| | - Rosarita D'Orsi
- Department of Chemistry and Industrial ChemistryUniversity of Pisavia Moruzzi 13Pisa56124Italy
| | - Marco Mattonai
- Department of Chemistry and Industrial ChemistryUniversity of Pisavia Moruzzi 13Pisa56124Italy
| | - Erika Ribechini
- Department of Chemistry and Industrial ChemistryUniversity of Pisavia Moruzzi 13Pisa56124Italy
| | - Alessandra Operamolla
- Department of Chemistry and Industrial ChemistryUniversity of Pisavia Moruzzi 13Pisa56124Italy
| | - Christian Teichert
- Chair of PhysicsDepartment of PhysicsMechanics and Electrical EngineeringMontanuniversität LeobenFranz Josef Str. 18Leoben8700Austria
| | - Chunlin Xu
- Laboratory of Natural Materials Technology/Wood and Paper ChemistryÅbo Akademi UniversityPorthansgatan 3‐5, ÅboTurku20500Finland
| | - Barbara Stadlober
- Joanneum Research ForschungsgesellschaftMaterialsFranz‐Pichler Str. Nr. 30Weiz8169Austria
| | - Niyazi Serdar Sariciftci
- Johannes Kepler University LinzDept. Physical ChemistryLinz Institute for Organic Solar Cells (LIOS)Altenberger Str. Nr. 69Linz4040Austria
| | - Mihai Irimia‐Vladu
- Joanneum Research ForschungsgesellschaftMaterialsFranz‐Pichler Str. Nr. 30Weiz8169Austria
- Johannes Kepler University LinzDept. Physical ChemistryLinz Institute for Organic Solar Cells (LIOS)Altenberger Str. Nr. 69Linz4040Austria
- Present address:
Mihai Irimia‐VladuJohannes Kepler University LinzInstitute of Physical ChemistryLinz Institute for Organic Solar Cells (LIOS)Altenberger Str. Nr. 69Linz40040Austria
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4
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Murastov G, Aslam MA, Tran TH, Lassnig A, Watanabe K, Taniguchi T, Wurster S, Nachtnebel M, Teichert C, Sheremet E, Rodriguez RD, Matkovic A. Photoinduced edge-specific nanoparticle decoration of two-dimensional tungsten diselenide nanoribbons. Commun Chem 2023; 6:166. [PMID: 37580376 PMCID: PMC10425467 DOI: 10.1038/s42004-023-00975-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Accepted: 08/03/2023] [Indexed: 08/16/2023] Open
Abstract
Metallic nanoparticles are widely explored for boosting light-matter coupling, optoelectronic response, and improving photocatalytic performance of two-dimensional (2D) materials. However, the target area is restricted to either top or bottom of the 2D flakes. Here, we introduce an approach for edge-specific nanoparticle decoration via light-assisted reduction of silver ions and merging of silver seeds. We observe arrays of the self-limited in size silver nanoparticles along tungsten diselenide WSe2 nanoribbon edges. The density of nanoparticles is tunable by adjusting the laser fluence. Scanning electron microscopy, atomic force microscopy, and Raman spectroscopy are used to investigate the size, distribution, and photo-response of the deposited plasmonic nanoparticles on the quasi-one-dimensional nanoribbons. We report an on-surface synthesis path for creating mixed-dimensional heterostructures and heterojunctions with potential applications in opto-electronics, plasmonics, and catalysis, offering improved light matter coupling, optoelectronics response, and photocatalytic performance of 2D materials.
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Affiliation(s)
- Gennadiy Murastov
- Chair of Physics, Department Physics, Mechanics and Electrical Engineering, Montanuniversität Leoben, Franz Josef Strasse 18, 8700, Leoben, Austria.
| | - Muhammad Awais Aslam
- Chair of Physics, Department Physics, Mechanics and Electrical Engineering, Montanuniversität Leoben, Franz Josef Strasse 18, 8700, Leoben, Austria
| | - Tuan-Hoang Tran
- Tomsk Polytechnic University, Lenina Avenue 30, 634034, Tomsk, Russia
| | - Alice Lassnig
- Erich Schmid Institute of Materials Science, Austrian Academy of Sciences, Jahnstrasse 12, 8700, Leoben, Austria
| | - Kenji Watanabe
- Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba, 305-0044, Japan
| | - Takashi Taniguchi
- International Center for Materials Nanoarchitectonics, National Institute for Materials Science, 1-1 Namiki, Tsukuba, 305-0044, Japan
| | - Stefan Wurster
- Erich Schmid Institute of Materials Science, Austrian Academy of Sciences, Jahnstrasse 12, 8700, Leoben, Austria
| | - Manfred Nachtnebel
- Graz Centre for Electron Microscopy (ZFE), Steyrergasse 17, 8010, Graz, Austria
| | - Christian Teichert
- Chair of Physics, Department Physics, Mechanics and Electrical Engineering, Montanuniversität Leoben, Franz Josef Strasse 18, 8700, Leoben, Austria
| | - Evgeniya Sheremet
- Tomsk Polytechnic University, Lenina Avenue 30, 634034, Tomsk, Russia
| | - Raul D Rodriguez
- Tomsk Polytechnic University, Lenina Avenue 30, 634034, Tomsk, Russia
| | - Aleksandar Matkovic
- Chair of Physics, Department Physics, Mechanics and Electrical Engineering, Montanuniversität Leoben, Franz Josef Strasse 18, 8700, Leoben, Austria.
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5
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Pan Y, Rahaman M, He L, Milekhin I, Manoharan G, Aslam MA, Blaudeck T, Willert A, Matković A, Madeira TI, Zahn DRT. Exciton tuning in monolayer WSe 2 via substrate induced electron doping. Nanoscale Adv 2022; 4:5102-5108. [PMID: 36504751 PMCID: PMC9680939 DOI: 10.1039/d2na00495j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Accepted: 10/25/2022] [Indexed: 06/17/2023]
Abstract
We report large exciton tuning in WSe2 monolayers via substrate induced non-degenerate doping. We observe a redshift of ∼62 meV for the A exciton together with a 1-2 orders of magnitude photoluminescence (PL) quenching when the monolayer WSe2 is brought in contact with highly oriented pyrolytic graphite (HOPG) compared to dielectric substrates such as hBN and SiO2. As the evidence of doping from HOPG to WSe2, a drastic increase of the intensity ratio of trions to neutral excitons was observed. Using a systematic PL and Kelvin probe force microscopy (KPFM) investigation on WSe2/HOPG, WSe2/hBN, and WSe2/graphene, we conclude that this unique excitonic behavior is induced by electron doping from the substrate. Our results propose a simple yet efficient way for exciton tuning in monolayer WSe2, which plays a central role in the fundamental understanding and further device development.
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Affiliation(s)
- Yang Pan
- Semiconductor Physics, Institute of Physics, Chemnitz University of Technology Chemnitz Germany
- Center for Materials, Architectures, and Integration of Nanomembranes (MAIN), Chemnitz University of Technology Chemnitz Germany
| | - Mahfujur Rahaman
- Department of Electrical and Systems Engineering, University of Pennsylvania Philadelphia PA USA
| | - Lu He
- Semiconductor Physics, Institute of Physics, Chemnitz University of Technology Chemnitz Germany
- Center for Materials, Architectures, and Integration of Nanomembranes (MAIN), Chemnitz University of Technology Chemnitz Germany
| | - Ilya Milekhin
- Semiconductor Physics, Institute of Physics, Chemnitz University of Technology Chemnitz Germany
- Center for Materials, Architectures, and Integration of Nanomembranes (MAIN), Chemnitz University of Technology Chemnitz Germany
| | - Gopinath Manoharan
- Center for Microtechnologies, Chemnitz University of Technology Chemnitz Germany
| | | | - Thomas Blaudeck
- Center for Materials, Architectures, and Integration of Nanomembranes (MAIN), Chemnitz University of Technology Chemnitz Germany
- Center for Microtechnologies, Chemnitz University of Technology Chemnitz Germany
- Fraunhofer Institute for Electronic Nano Systems Chemnitz Germany
| | - Andreas Willert
- Fraunhofer Institute for Electronic Nano Systems Chemnitz Germany
| | | | - Teresa I Madeira
- Semiconductor Physics, Institute of Physics, Chemnitz University of Technology Chemnitz Germany
- Center for Materials, Architectures, and Integration of Nanomembranes (MAIN), Chemnitz University of Technology Chemnitz Germany
| | - Dietrich R T Zahn
- Semiconductor Physics, Institute of Physics, Chemnitz University of Technology Chemnitz Germany
- Center for Materials, Architectures, and Integration of Nanomembranes (MAIN), Chemnitz University of Technology Chemnitz Germany
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6
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Maqsood R, Khan A, Mushtaq MH, Yaqub T, Aslam MA, Rashid HB, Gill SS, Akram R, Rehman A, Chaudhry M. Risk factors for outbreaks caused by variant strain of Newcastle disease on environmentally controlled broiler chicken farms in Lahore, Pakistan. Pol J Vet Sci 2021; 24:497-503. [PMID: 35179843 DOI: 10.24425/pjvs.2021.139974] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Newcastle disease (ND) is a frequently reported disease in poultry among both vaccinated and non-vaccinated flocks in Pakistan. During 2011-2012 poultry industry in Punjab, mainly in Lahore region, faced fatal outbreaks of ND caused by a variant strain. An analytical study was conducted during outbreak period in Lahore region. A total of 114 environmentally controlled farms were selected with the help of convenient sampling method. A questionnaire was designed about the potential risk factors associated with the spread of ND outbreak. The bivariate relationships between ND status and independent variables were investigated by applying the Chi-square and Fisher's exact test. Multivariable logistic model was used to estimate the effect of each studied variable on the outcome by adjusting the other variables in the model. The variables which showed an association with ND outbreaks at commercial poultry farms were improper method for dead birds disposal (OR=4.96; 95% CI 1.63-15.12), use of same feed transporting vehicle at multiple poultry farms (OR=4.92; 95% CI 1.58-15.33), farm to farm distance of less than 1 km (OR=9.32; 95% CI(1.19-73.12), number of sheds at one farm (OR=2.31; 95% CI 0.93-5.69), labor type (OR=2.72; 95% CI 0.83-8.88) and biosecurity (OR= 4.47; 95% CI 0.56-35.66).
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Affiliation(s)
- R Maqsood
- Department of Epidemiology and Public Health, University of Veterinary and Animal Sciences, Lahore-Pakistan
- Institute of Continuing Education and Extension, University of Veterinary and Animal Sciences, Lahore-Pakistan
| | - A Khan
- Department of Epidemiology and Public Health, University of Veterinary and Animal Sciences, Lahore-Pakistan
| | - M H Mushtaq
- Department of Epidemiology and Public Health, University of Veterinary and Animal Sciences, Lahore-Pakistan
| | - T Yaqub
- Institute of Microbiology, University of Veterinary and Animal Sciences, Lahore-Pakistan
| | - M A Aslam
- Office of Research Innovation and Commercialization, University of Veterinary and Animal Sciences, Lahore-Pakistan
| | - H B Rashid
- Department of Veterinary Surgery and Pet Sciences, University of Veterinary and Animal Sciences, Lahore-Pakistan
| | - S S Gill
- Department of Epidemiology and Public Health, University of Veterinary and Animal Sciences, Lahore-Pakistan
| | - R Akram
- Department of Epidemiology and Public Health, University of Veterinary and Animal Sciences, Lahore-Pakistan
| | - A Rehman
- Department of Epidemiology and Public Health, University of Veterinary and Animal Sciences, Lahore-Pakistan
| | - M Chaudhry
- Department of Epidemiology and Public Health, University of Veterinary and Animal Sciences, Lahore-Pakistan
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7
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Aslam MA, Riaz K, Mahmood MQ, Zubair M. Hybrid analytical-numerical approach for investigation of differential effects in normal and cancer cells under electroporation. RSC Adv 2019; 9:41518-41530. [PMID: 35541630 PMCID: PMC9076493 DOI: 10.1039/c9ra07428g] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2019] [Accepted: 12/05/2019] [Indexed: 01/31/2023] Open
Abstract
Electroporation has offered important biomedical applications in electrochemotherapy, tissue ablation and gene editing recently. Time and computation efficient analytical and numerical models should be developed to understand the differential effects of electroporation on normal and cancer cells. In this work, we present a hybrid analytical-numerical approach to investigate the behavior of normal and cancer cells under electroporation. We have compared the human breast cancer cell (MCF-7) and non-tumorigenic human breast cell (MCF-10A) under electroporation in terms of change in transmembrane voltage and pore formation on cell surface. The effects of electric pulse time, amplitude and membrane conductivity variation are analyzed in a systematic manner. To accelerate the calculation of transmembrane voltage, we have introduced a simple Multilayer Electric Potential Model (MEPM) which calculates the potential distribution across the cell analytically. The MEPM calculates electric potential distribution across a biological cell sandwiched between two semi-circular electrodes held at fixed potential, by solving the Laplace's equation over an equivalent planar, multilayer geometry. The MEPM model is then used in a Finite Element Method (FEM) based numerical model of electroporation. Transmembrane voltage and pore density for electroporated MCF-10A are estimated to be 1.31 V and 2.98 × 1013 m-2 respectively, and for MCF-7 the estimated values are 0.53 V and 1.93 × 1014 m-2, respectively. Our results suggest that under electroporation, the cancer cell's membrane get much more permeabilized than its counterpart normal cell even at small values of transmembrane voltage. This work provides a theoretical basis for further experimental exploration of electroporation process in cancer therapy, and serves as a design tool for performance optimization.
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Affiliation(s)
- Muhammad Awais Aslam
- Electrical Engineering Department, Information Technology University 54000 Lahore Pakistan
| | - Kashif Riaz
- Electrical Engineering Department, Information Technology University 54000 Lahore Pakistan
| | - Muhammad Qasim Mahmood
- Electrical Engineering Department, Information Technology University 54000 Lahore Pakistan
| | - Muhammad Zubair
- Electrical Engineering Department, Information Technology University 54000 Lahore Pakistan
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8
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Bukhari M, Aslam MA, Khan A, Iram Q, Akbar A, Naz AG, Ahmad S, Ahmad MM, Ashfaq UA, Aziz H, Ali M. TLR8 gene polymorphism and association in bacterial load in southern Punjab of Pakistan: an association study with pulmonary tuberculosis. Int J Immunogenet 2015; 42:46-51. [PMID: 25572425 DOI: 10.1111/iji.12170] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2014] [Revised: 10/13/2014] [Accepted: 12/01/2014] [Indexed: 01/24/2023]
Abstract
Only 5-10% of people infected with Mycobacterium tuberculosis develop active tuberculosis which suggests a role of genetic variation in host immunity. Genetic variants in TLRs are potential indicator for host susceptibility and outcome of several diseases. We explored the association of nonsynonymous genetic variants (Met1Val) with Toll-like receptor 8 in Pakistani population. Genotypic and allelic distribution of TLR8 polymorphism (rs3764880) in patients with TB and healthy donors from different areas of southern Punjab, Pakistan, was determined. Results provide that our population is highly influenced by TLR8 Met1Val SNP for TB, and G allele appeared to increase TB susceptibility. Mutant genotype GG or G/- and G allele was significantly higher among all the categories of cases than in controls. Among different levels of bacillary load and genotypes, GG or G/- and G allele significantly supports the incidence of 2 + class for bacterial load.
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Affiliation(s)
- M Bukhari
- Institute of Molecular Biology and Biotechnology, Bahauddin Zakariya University, Multan, Pakistan
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9
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Khan AUH, Aslam MA, Hussain I, Naz AG, Rana IA, Ahmad MM, Ali M, Ahmad S. Role of Toll-like receptor 2 (-196 to -174) polymorphism in susceptibility to pulmonary tuberculosis in Pakistani population. Int J Immunogenet 2013; 41:105-11. [PMID: 23998736 DOI: 10.1111/iji.12086] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2012] [Revised: 07/05/2013] [Accepted: 08/08/2013] [Indexed: 12/22/2022]
Abstract
Tuberculosis (TB) is a global public health problem and a source of preventable deaths each year, with 8.8 million new cases of TB and 1.6 million deaths worldwide. Pakistan ranks sixth on the list of 22 high-burden tuberculosis countries in the world. The transitions from infection to clinical disease are very few signifying that host-defence factors could lead to the development of active disease. Toll-like receptor (TLR) 2 polymorphisms have been associated with regulation of TLR expression and development of active TB. In this study, blood samples of 187 subjects including 100 healthy and 87 TB positive were collected from three districts of Pakistan. DNA was extracted from blood and TLR 2 (-196 to -174del) polymorphism was analysed by polymerase chain reaction (PCR). The results suggest that the frequency of -196 to -174del/del polymorphism of TLR2 was significantly higher in TB-positive patients compared with healthy. Results revealed that (-196 to -174del) polymorphism may increase the susceptibility to TB in healthy population of Pakistan. Moreover, males with heterozygous genotype (I/D) are more prone to TB than females with the same genotype. The occurrence of TB infection has been found positively associated with the age, suggesting that the population within the range of 21-45 years is more susceptible to Mycobacterium tuberculosis than other age groups studied. A significant association is also observed between smoking and the chances of developing TB, confirming that smoking strongly promotes its incidence.
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Affiliation(s)
- Abrar-Ul-Haq Khan
- Institute of Microbiology, University of Agriculture Faisalabad, Faisalabad, Pakistan
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10
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Shahnawaz S, Ali M, Aslam MA, Fatima R, Chaudhry ZI, Hassan MU, Ali M, Iqbal F. A study on the prevalence of a tick-transmitted pathogen, Theileria annulata, and hematological profile of cattle from Southern Punjab (Pakistan). Parasitol Res 2011; 109:1155-60. [PMID: 21451992 DOI: 10.1007/s00436-011-2360-1] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2011] [Accepted: 03/16/2011] [Indexed: 11/30/2022]
Abstract
The present study was carried out to determine the prevalence of Theileria annulata in large ruminants in Southern Punjab (Pakistan). Blood samples were collected from 144 large ruminants, consisting of 105 cattle and 39 buffaloes, from six districts of Southern Punjab including Multan, Layyah, Muzaffar Garh, Bhakar, Bahawalnagar, and Vehari. Data on the characteristics of the animals and herds were collected through questionnaires. The age of animals (P = 0.02), presence of ticks on animals (P = 0.02), and presence of ticks on dogs associated with herds (P = 0.05) were among the major risk factors involved in the spread of tropical theileriosis in the study area. Two different parasite detection techniques, PCR amplification and screening of Giemsa-stained slides, were compared, and it was found that PCR amplification is a more sensitive tool (19% parasite detection) as compared to smear scanning (3% parasite detection) for the detection of T. annulata. Twenty eight out of 144 animals produced the 721-bp fragment specific for T. annulata from five out of six sampling districts. Different blood (hemoglobin, glucose) and serum (ALT, AST, LDH, cholesterol) parameters of calves and cattle were measured and compared between parasite-positive and parasite-negative samples to assess the effect of T. annulata on the blood and serological profile of infected animals.
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Affiliation(s)
- S Shahnawaz
- Zoology Division, Institute of Pure and Applied Biology, Bahauddin Zakariya University, Multan 60800, Pakistan
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Arya AK, El-Fert A, Devling T, Eccles RM, Aslam MA, Rubbi CP, Vlatković N, Fenwick J, Lloyd BH, Sibson DR, Jones TM, Boyd MT. Nutlin-3, the small-molecule inhibitor of MDM2, promotes senescence and radiosensitises laryngeal carcinoma cells harbouring wild-type p53. Br J Cancer 2010; 103:186-95. [PMID: 20588277 PMCID: PMC2906734 DOI: 10.1038/sj.bjc.6605739] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
BACKGROUND Primary radiotherapy (RT) is a mainstay of treatment for laryngeal squamous cell carcinoma (LSCC). Although the cure rates for early (T1) vocal cord tumours are high, RT proves ineffective in up to a third of T3 carcinomas. Moreover, RT is associated with debilitating early- and late-treatment-related toxicity, thus finding means to de-escalate therapy, while retaining/augmenting therapeutic effectiveness, is highly desirable. p53 is a key mediator of radiation responses; we therefore investigated whether Nutlin-3, a small-molecule inhibitor of MDM2 (mouse double minute 2; an essential negative regulator of p53), might radiosensitise LSCC cells. METHODS We performed clonogenic assays to measure radiosensitivity in a panel of LSCC cell lines (for which we determined p53 mutational status) in the presence and absence of Nutlin-3. RESULTS LSCC cells harbouring wild-type p53 were significantly radiosensitised by Nutlin-3 (P<0.0001; log-rank scale), and displayed increased cell cycle arrest and significantly increased senescence (P<0.001) in the absence of increased apoptosis; thus, our data suggest that senescence may mediate this increased radiosensitivity. CONCLUSION This is the first study showing Nutlin-3 as an effective radiosensitiser in LSCC cells that retain wild-type p53. The clinical application of Nutlin-3 might improve local recurrence rates or allow treatment de-escalation in these patients.
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Affiliation(s)
- A K Arya
- Division of Surgery and Oncology, School of Cancer Studies, University of Liverpool, 5th Floor. UCD Building, Daulby Street, Liverpool L69 3GA, UK
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Aslam MA, Awan FR, Tauseef I, Ali S, Ahmad N, Malik NA, Riaz MN, Qureshi JA. Identification of hepatitis B virus core mutants by PCR-RFLP in chronic hepatitis B patients from Punjab, Pakistan. Arch Virol 2007; 153:163-70. [PMID: 18030544 DOI: 10.1007/s00705-007-1093-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2007] [Accepted: 09/25/2007] [Indexed: 01/20/2023]
Abstract
Chronic hepatitis B virus (HBV) infection remains a major health issue worldwide. Several factors including core gene variation are responsible for the development of chronicity of HBV infection. The present study was designed to identify the variations in the core region of the HBV genome in a local population of chronic hepatitis B patients (n = 57) using a PCR-based restriction fragment length polymorphism (PCR-RFLP) method. Fifty subjects were found to be positive for the presence of HBV DNA. For the core region genotyping, the Ava II and Msp I restriction enzymes were used. Mutations at nucleotide (nt) 2147 and nt 2362 in the HBV genome in the core region for Ava II (A4 type, 74%) and nt 2331 for Msp I (M1 type, 66%) were observed as the most common pattern. These results are different from those of previously reported studies on other populations and thus appear to be unique to the Pakistani population. This type of characterization of core mutants may be useful for the design of vaccines based on viral epitopes that are effective for the Pakistani population. Moreover, these unique genotypic patterns for the HBV core gene might be some of the main factors responsible for understanding the underlying mechanism by which HBV chronicity is developed in the Pakistani population.
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Affiliation(s)
- M A Aslam
- Health Biotechnology Division, National Institute for Biotechnology and Genetic Engineering (NIBGE), Faisalabad, Pakistan.
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