1
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Soni N, Chandra Verma N, Talor N, Meller A. Over 30-Fold Enhancement in DNA Translocation Dynamics through Nanoscale Pores Coated with an Anionic Surfactant. NANO LETTERS 2023; 23:4609-4616. [PMID: 37149783 DOI: 10.1021/acs.nanolett.3c01096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Solid-state nanopores (ssNPs) are single-molecule sensors capable of label-free quantification of different biomolecules, which have become highly versatile with the introduction of different surface treatments. By modulating the surface charges of the ssNP, the electro-osmotic flow (EOF) can be controlled in turn affecting the in-pore hydrodynamic forces. Herein, we demonstrate that negative charge surfactant coating to ssNPs generates EOF that slows-down DNA translocation speed by >30-fold, without deterioration of the NP noise, hence significantly improving its performances. Consequently, surfactant-coated ssNPs can be used to reliably sense short DNA fragments at high voltage bias. To shed light on the EOF phenomena inside planar ssNPs, we introduce visualization of the electrically neutral fluorescent molecule's flow, hence decoupling the electrophoretic from EOF forces. Finite elements simulations are then used to show that EOF is likely responsible for in-pore drag and size-selective capture rate. This study broadens ssNPs use for multianalyte sensing in a single device.
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Affiliation(s)
- Neeraj Soni
- Russell Berrie Nanotechnology Institute, Technion IIT, Haifa 3200003, Israel
- Department of Biomedical Engineering, Technion IIT, Haifa 3200003, Israel
| | | | - Noam Talor
- Department of Biomedical Engineering, Technion IIT, Haifa 3200003, Israel
| | - Amit Meller
- Russell Berrie Nanotechnology Institute, Technion IIT, Haifa 3200003, Israel
- Department of Biomedical Engineering, Technion IIT, Haifa 3200003, Israel
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2
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Soni N, Freundlich N, Ohayon S, Huttner D, Meller A. Single-File Translocation Dynamics of SDS-Denatured, Whole Proteins through Sub-5 nm Solid-State Nanopores. ACS NANO 2022; 16:11405-11414. [PMID: 35785960 PMCID: PMC7613183 DOI: 10.1021/acsnano.2c05391] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The ability to routinely identify and quantify the complete proteome from single cells will greatly advance medicine and basic biology research. To meet this challenge of single-cell proteomics, single-molecule technologies are being developed and improved. Most approaches, to date, rely on the analysis of polypeptides, resulting from digested proteins, either in solution or immobilized on a surface. Nanopore biosensing is an emerging single-molecule technique that circumvents surface immobilization and is optimally suited for the analysis of long biopolymers, as has already been shown for DNA sequencing. However, proteins, unlike DNA molecules, are not uniformly charged and harbor complex tertiary structures. Consequently, the ability of nanopores to analyze unfolded full-length proteins has remained elusive. Here, we evaluate the use of heat denaturation and the anionic surfactant sodium dodecyl sulfate (SDS) to facilitate electrokinetic nanopore sensing of unfolded proteins. Specifically, we characterize the voltage dependence translocation dynamics of a wide molecular weight range of proteins (from 14 to 130 kDa) through sub-5 nm solid-state nanopores, using a SDS concentration below the critical micelle concentration. Our results suggest that proteins' translocation dynamics are significantly slower than expected, presumably due to the smaller nanopore diameters used in our study and the role of the electroosmotic force opposing the translocation direction. This allows us to distinguish among the proteins of different molecular weights based on their dwell time and electrical charge deficit. Given the simplicity of the protein denaturation assay and circumvention of the tailor-made necessities for sensing protein of different folded sizes, shapes, and charges, this approach can facilitate the development of a whole proteome identification technique.
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Affiliation(s)
- Neeraj Soni
- Department
of Biomedical Engineering, Technion−IIT, Haifa, 3200003 Israel
- Russell
Berrie Nanotechnology Institute Technion−IIT, Haifa, 3200003 Israel
| | - Noam Freundlich
- Department
of Biomedical Engineering, Technion−IIT, Haifa, 3200003 Israel
| | - Shilo Ohayon
- Department
of Biomedical Engineering, Technion−IIT, Haifa, 3200003 Israel
| | - Diana Huttner
- Department
of Biomedical Engineering, Technion−IIT, Haifa, 3200003 Israel
| | - Amit Meller
- Department
of Biomedical Engineering, Technion−IIT, Haifa, 3200003 Israel
- Russell
Berrie Nanotechnology Institute Technion−IIT, Haifa, 3200003 Israel
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3
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Ying C, Ma T, Xu L, Rahmani M. Localized Nanopore Fabrication via Controlled Breakdown. NANOMATERIALS 2022; 12:nano12142384. [PMID: 35889608 PMCID: PMC9323289 DOI: 10.3390/nano12142384] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Revised: 07/01/2022] [Accepted: 07/07/2022] [Indexed: 12/03/2022]
Abstract
Nanopore sensors provide a unique platform to detect individual nucleic acids, proteins, and other biomolecules without the need for fluorescent labeling or chemical modifications. Solid-state nanopores offer the potential to integrate nanopore sensing with other technologies such as field-effect transistors (FETs), optics, plasmonics, and microfluidics, thereby attracting attention to the development of commercial instruments for diagnostics and healthcare applications. Stable nanopores with ideal dimensions are particularly critical for nanopore sensors to be integrated into other sensing devices and provide a high signal-to-noise ratio. Nanopore fabrication, although having benefited largely from the development of sophisticated nanofabrication techniques, remains a challenge in terms of cost, time consumption and accessibility. One of the latest developed methods—controlled breakdown (CBD)—has made the nanopore technique broadly accessible, boosting the use of nanopore sensing in both fundamental research and biomedical applications. Many works have been developed to improve the efficiency and robustness of pore formation by CBD. However, nanopores formed by traditional CBD are randomly positioned in the membrane. To expand nanopore sensing to a wider biomedical application, controlling the localization of nanopores formed by CBD is essential. This article reviews the recent strategies to control the location of nanopores formed by CBD. We discuss the fundamental mechanism and the efforts of different approaches to confine the region of nanopore formation.
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Affiliation(s)
- Cuifeng Ying
- Advanced Optics and Photonics Laboratory, Department of Engineering, School of Science &Technology, Nottingham Trent University, Nottingham NG1 4FQ, UK; (L.X.); (M.R.)
- Correspondence:
| | - Tianji Ma
- Hunan Provincial Key Laboratory of Materials Protection for Electric Power and Transportation & Hunan Provincial Key Laboratory of Cytochemistry, School of Chemistry and Chemical Engineering, Changsha University of Science and Technology, Changsha 410114, China;
| | - Lei Xu
- Advanced Optics and Photonics Laboratory, Department of Engineering, School of Science &Technology, Nottingham Trent University, Nottingham NG1 4FQ, UK; (L.X.); (M.R.)
| | - Mohsen Rahmani
- Advanced Optics and Photonics Laboratory, Department of Engineering, School of Science &Technology, Nottingham Trent University, Nottingham NG1 4FQ, UK; (L.X.); (M.R.)
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4
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van Kooten XF, Rozevsky Y, Marom Y, Ben Sadeh E, Meller A. Purely electrical SARS-CoV-2 sensing based on single-molecule counting. NANOSCALE 2022; 14:4977-4986. [PMID: 35258059 PMCID: PMC8969453 DOI: 10.1039/d1nr07787b] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Accepted: 03/03/2022] [Indexed: 05/23/2023]
Abstract
The majority of RNA based COVID-19 diagnostics employ enzymatic amplification to achieve high sensitivity, but this relies on arbitrary thresholding, which complicates the comparison of test results and may lead to false outcomes. Here we introduce solid-state nanopore sensing for label-free quantification of SARS-CoV-2 RNA in clinical nasal swab samples. This PCR-free method involves reverse transcribing a target gene on the viral RNA before enzymatically digesting all but the resulting dsDNA. Ratiometric quantification of RNA abundance is achieved by single-molecule counting and length-based nanopore identification of dsDNA from a SARS-CoV-2 gene and a human reference gene. We graded nasal swab samples from >15 subjects and find that the SARS-CoV-2 ratiometric nanopore index correlates well with the reported RT-qPCR threshold cycle for positive classified samples. Remarkably, nanopore analysis also reports quantitative positive outcomes for clinical samples classified as negative by RT-qPCR, suggesting that the method may be used to diagnose COVID-19 in samples that may evade detection. We show that the sample preparation workflow can be implemented using a compact microfluidic device with integrated thermal control for semi-automated processing of extremely small sample volumes, offering a viable route towards automated, fast and affordable RNA quantification in a small and portable device.
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Affiliation(s)
| | - Yana Rozevsky
- Department of Biomedical Engineering, Technion-IIT, Haifa 32000, Israel.
| | - Yulia Marom
- Department of Biomedical Engineering, Technion-IIT, Haifa 32000, Israel.
| | - Efrat Ben Sadeh
- Department of Biomedical Engineering, Technion-IIT, Haifa 32000, Israel.
| | - Amit Meller
- Department of Biomedical Engineering, Technion-IIT, Haifa 32000, Israel.
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5
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Zheng G, Liu X, Wu J, Zhang D, Zhang D, Xu Z, Cui Y, Qiu J, Strek W. Boosting Continuous-Wave Laser-Driven Nonlinear Photothermal White Light Generation by Nanoscale Porosity. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2106368. [PMID: 34891218 DOI: 10.1002/adma.202106368] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Revised: 11/17/2021] [Indexed: 06/13/2023]
Abstract
The irradiation of an optically absorptive medium by a continuous-wave (CW) near-infrared (NIR) laser can result in a spectral continuum emission covering both the visible and NIR regions, which is attractive for applications as continuum light sources in diverse fields. It is shown here that this NIR-laser-driven light emission can be effectively modulated with nanoscale architecture in the medium. By using porous silica as the model matrix and Yb3+ ions as the photothermally active centers, up to 100 folds increment in NIR-laser-induced emission intensity and dramatic decrease in threshold excitation density are demonstrated. It is observed that the emission intensity exhibits a strong nonlinear dependence on the power of the NIR excitation laser, featuring clear excitation power thresholds. Based on combined numerical simulation and spectral and temperature measurements, the improved broadband emission and photothermal nonlinearity are interpreted by enhanced optical energy localization around the laser spot that results in boosting the photon-to-photon conversion efficiency. The use of the nonlinear photothermal emission process as a broadband NIR light source, which could be exploited for applications including NIR spectroscopy, imaging, and sensing, is further demonstrated as a proof-of-concept.
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Affiliation(s)
- Guojun Zheng
- College of Optical Science and Engineering, Zhejiang University, Hangzhou, 310027, P. R. China
| | - Xiaofeng Liu
- School of Materials Science and Engineering, Zhejiang University, Hangzhou, 310027, P. R. China
| | - Jianhong Wu
- College of Physics and Optoelectronics, Taiyuan University of Technology, Taiyuan, 030000, P. R. China
| | - Dao Zhang
- College of Optical Science and Engineering, Zhejiang University, Hangzhou, 310027, P. R. China
| | - Duoduo Zhang
- School of Materials Science and Engineering, Zhejiang University, Hangzhou, 310027, P. R. China
| | - Zhousu Xu
- Institute of Intelligent Optoelectronic Technology, Zhejiang University of Technology, Hangzhou, 310027, P. R. China
| | - Yanxia Cui
- College of Physics and Optoelectronics, Taiyuan University of Technology, Taiyuan, 030000, P. R. China
| | - Jianrong Qiu
- College of Optical Science and Engineering, Zhejiang University, Hangzhou, 310027, P. R. China
- CAS Center for Excellence in Ultra-Intense Laser Science, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai, 201800, P. R. China
| | - Wieslaw Strek
- Institute of Low Temperatures and Structural Research, Polish Academy of Sciences, Wroclaw, 50-422, Poland
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6
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Fried JP, Wu Y, Tilley RD, Gooding JJ. Optical Nanopore Sensors for Quantitative Analysis. NANO LETTERS 2022; 22:869-880. [PMID: 35089719 DOI: 10.1021/acs.nanolett.1c03976] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Nanopore sensors have received significant interest for the detection of clinically important biomarkers with single-molecule resolution. These sensors typically operate by detecting changes in the ionic current through a nanopore due to the translocation of an analyte. Recently, there has been interest in developing optical readout strategies for nanopore sensors for quantitative analysis. This is because they can utilize wide-field microscopy to independently monitor many nanopores within a high-density array. This significantly increases the amount of statistics that can be obtained, thus enabling the analysis of analytes present at ultralow concentrations. Here, we review the use of optical nanopore sensing strategies for quantitative analysis. We discuss optical nanopore sensing assays that have been developed to detect clinically relevant biomarkers, the potential for multiplexing such measurements, and techniques to fabricate high density arrays of nanopores with a view toward the use of these devices for clinical applications.
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Affiliation(s)
- Jasper P Fried
- School of Chemistry, Australian Centre for NanoMedicine, ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, The University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Yanfang Wu
- School of Chemistry, Australian Centre for NanoMedicine, ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, The University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Richard D Tilley
- School of Chemistry, Australian Centre for NanoMedicine, ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, The University of New South Wales, Sydney, New South Wales 2052, Australia
| | - J Justin Gooding
- School of Chemistry, Australian Centre for NanoMedicine, ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, The University of New South Wales, Sydney, New South Wales 2052, Australia
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7
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Zhang Y, Ma D, Gu Z, Zhan L, Sha J. Fast Fabrication of Solid-State Nanopores for DNA Molecule Analysis. NANOMATERIALS 2021; 11:nano11092450. [PMID: 34578767 PMCID: PMC8468320 DOI: 10.3390/nano11092450] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 09/16/2021] [Accepted: 09/16/2021] [Indexed: 01/20/2023]
Abstract
Solid-state nanopores have been developed as a prominent tool for single molecule analysis in versatile applications. Although controlled dielectric breakdown (CDB) is the most accessible method for a single nanopore fabrication, it is still necessary to improve the fabrication efficiency and avoid the generation of multiple nanopores. In this work, we treated the SiNx membranes in the air–plasma before the CDB process, which shortened the time-to-pore-formation by orders of magnitude. λ-DNA translocation experiments validated the functionality of the pore and substantiated the presence of only a single pore on the membrane. Our fabricated pore could also be successfully used to detect short single-stranded DNA (ssDNA) fragments. Using to ionic current signals, ssDNA fragments with different lengths could be clearly distinguished. These results will provide a valuable reference for the nanopore fabrication and DNA analysis.
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Affiliation(s)
- Yin Zhang
- Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments, School of Mechanical Engineering, Southeast University, Nanjing 211189, China; (D.M.); (Z.G.); (L.Z.)
- Correspondence: (Y.Z.); (J.S.)
| | - Dexian Ma
- Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments, School of Mechanical Engineering, Southeast University, Nanjing 211189, China; (D.M.); (Z.G.); (L.Z.)
- China Aerospace Science & Industry Nanjing Chenguang Group, Nanjing 210006, China
| | - Zengdao Gu
- Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments, School of Mechanical Engineering, Southeast University, Nanjing 211189, China; (D.M.); (Z.G.); (L.Z.)
| | - Lijian Zhan
- Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments, School of Mechanical Engineering, Southeast University, Nanjing 211189, China; (D.M.); (Z.G.); (L.Z.)
| | - Jingjie Sha
- Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments, School of Mechanical Engineering, Southeast University, Nanjing 211189, China; (D.M.); (Z.G.); (L.Z.)
- Correspondence: (Y.Z.); (J.S.)
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8
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Fried JP, Swett JL, Nadappuram BP, Fedosyuk A, Sousa PM, Briggs DP, Ivanov AP, Edel JB, Mol JA, Yates JR. Understanding Electrical Conduction and Nanopore Formation During Controlled Breakdown. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2021; 17:e2102543. [PMID: 34337856 DOI: 10.1002/smll.202102543] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Revised: 07/01/2021] [Indexed: 06/13/2023]
Abstract
Controlled breakdown has recently emerged as a highly appealing technique to fabricate solid-state nanopores for a wide range of biosensing applications. This technique relies on applying an electric field of approximately 0.4-1 V nm-1 across the membrane to induce a current, and eventually, breakdown of the dielectric. Although previous studies have performed controlled breakdown under a range of different conditions, the mechanism of conduction and breakdown has not been fully explored. Here, electrical conduction and nanopore formation in SiNx membranes during controlled breakdown is studied. It is demonstrated that for Si-rich SiNx , oxidation reactions that occur at the membrane-electrolyte interface limit conduction across the dielectric. However, for stoichiometric Si3 N4 the effect of oxidation reactions becomes relatively small and conduction is predominately limited by charge transport across the dielectric. Several important implications resulting from understanding this process are provided which will aid in further developing controlled breakdown in the coming years, particularly for extending this technique to integrate nanopores with on-chip nanostructures.
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Affiliation(s)
- Jasper P Fried
- Department of Materials, University of Oxford, Oxford, OX1 3PH, UK
| | - Jacob L Swett
- Department of Materials, University of Oxford, Oxford, OX1 3PH, UK
| | | | | | - Pedro Miguel Sousa
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, Oeiras, 2780-157, Portugal
| | - Dayrl P Briggs
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN, 37830, USA
| | | | - Joshua B Edel
- Department of Chemistry, Imperial College London, London, W12 0BZ, UK
| | - Jan A Mol
- School of Physics and Astronomy, Queen Mary University London, London, E1 4NS, UK
| | - James R Yates
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, Oeiras, 2780-157, Portugal
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9
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Zvuloni E, Zrehen A, Gilboa T, Meller A. Fast and Deterministic Fabrication of Sub-5 Nanometer Solid-State Pores by Feedback-Controlled Laser Processing. ACS NANO 2021; 15:12189-12200. [PMID: 34219449 PMCID: PMC8320231 DOI: 10.1021/acsnano.1c03773] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Accepted: 06/28/2021] [Indexed: 05/26/2023]
Abstract
Nanopores are single-molecule sensors capable of detecting and quantifying a broad range of unlabeled biomolecules including DNA and proteins. Nanopores' generic sensing principle has permitted the development of a vast range of biomolecular applications in genomics and proteomics, including single-molecule DNA sequencing and protein fingerprinting. Owing to their superior mechanical and electrical stability, many of the recent studies involved synthetic nanopores fabricated in thin solid-state membranes such as freestanding silicon nitride. However, to date, one of the bottlenecks in this field is the availability of a fast, reliable, and deterministic fabrication method capable of repeatedly forming small nanopores (i.e., sub 5 nm) in situ. Recently, it was demonstrated that a tightly focused laser beam can induce controlled etching of silicon nitride membranes suspended in buffered aqueous solutions. Herein, we demonstrate that nanopore laser drilling (LD) can produce nanopores deterministically to a prespecified size without user intervention. By optimizing the optical apparatus, and by designing a multistep control algorithm for the LD process, we demonstrate a fully automatic fabrication method for any user-defined nanopore size within minutes. The LD process results in a double bowl-shaped structure having a typical size of the laser point-spread function (PSF) at its openings. Numerical simulations of the characteristic LD nanopore shape provide conductance curves that fit the experimental result and support the idea that the pore is produced at the thinnest area formed by the back-to-back facings bowls. The presented LD fabrication method significantly enhances nanopore fabrication throughput and accuracy and hence can be adopted for a large range of biomolecular sensing applications.
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Affiliation(s)
- Eran Zvuloni
- Department
of Biomedical Engineering, Technion-IIT, Haifa 32000, Israel
| | - Adam Zrehen
- Department
of Biomedical Engineering, Technion-IIT, Haifa 32000, Israel
| | - Tal Gilboa
- Department
of Pathology, Brigham and Women’s
Hospital, Harvard Medical School, Boston, Massachusetts 02115, United States
- Wyss
Institute for Biologically Inspired Engineering, Harvard University, Boston, Massachusetts 02115, United States
| | - Amit Meller
- Department
of Biomedical Engineering, Technion-IIT, Haifa 32000, Israel
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10
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Fried JP, Swett JL, Nadappuram BP, Mol JA, Edel JB, Ivanov AP, Yates JR. In situ solid-state nanopore fabrication. Chem Soc Rev 2021; 50:4974-4992. [PMID: 33623941 DOI: 10.1039/d0cs00924e] [Citation(s) in RCA: 47] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Nanopores in solid-state membranes are promising for a wide range of applications including DNA sequencing, ultra-dilute analyte detection, protein analysis, and polymer data storage. Techniques to fabricate solid-state nanopores have typically been time consuming or lacked the resolution to create pores with diameters down to a few nanometres, as required for the above applications. In recent years, several methods to fabricate nanopores in electrolyte environments have been demonstrated. These in situ methods include controlled breakdown (CBD), electrochemical reactions (ECR), laser etching and laser-assisted controlled breakdown (la-CBD). These techniques are democratising solid-state nanopores by providing the ability to fabricate pores with diameters down to a few nanometres (i.e. comparable to the size of many analytes) in a matter of minutes using relatively simple equipment. Here we review these in situ solid-state nanopore fabrication techniques and highlight the challenges and advantages of each method. Furthermore we compare these techniques by their desired application and provide insights into future research directions for in situ nanopore fabrication methods.
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Affiliation(s)
- Jasper P Fried
- Department of Materials, University of Oxford, Oxford, OX1 3PH, UK
| | - Jacob L Swett
- Department of Materials, University of Oxford, Oxford, OX1 3PH, UK
| | - Binoy Paulose Nadappuram
- Department of Chemistry, Imperial College London, Molecular Science Research Hub, White City Campus, 82 Wood Lane, W12 0BZ, UK
| | - Jan A Mol
- School of Physics and Astronomy, Queen Mary University of London, Mile End Road, E1 4NS, UK
| | - Joshua B Edel
- Department of Chemistry, Imperial College London, Molecular Science Research Hub, White City Campus, 82 Wood Lane, W12 0BZ, UK
| | - Aleksandar P Ivanov
- Department of Chemistry, Imperial College London, Molecular Science Research Hub, White City Campus, 82 Wood Lane, W12 0BZ, UK
| | - James R Yates
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, 2780-157 Oeiras, Portugal.
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11
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Leung C, Briggs K, Laberge MP, Peng S, Waugh M, Tabard-Cossa V. Mechanisms of solid-state nanopore enlargement under electrical stress. NANOTECHNOLOGY 2020; 31:44LT01. [PMID: 32698174 DOI: 10.1088/1361-6528/aba86e] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
We present a thorough exploration of nanopore growth under electrical stress in electrolyte solution, and demonstrate that despite their superficial similarities, nanopore formation by controlled breakdown (CBD) and nanopore growth under moderate voltage stress are fundamentally different processes. In particular, we demonstrate that unlike the CBD process, nanopore growth is primarily driven by the level of ionic current passing through the nanopore, rather than the strength of the electric field generating the current, and that enlargement has a much weaker pH dependence than does CBD pore formation. In combination with other works in the field, our results suggest that despite clear current-dependence, Joule heating is unlikely to be the main driver of pore growth during electrical stress, pointing instead toward electrochemical dissolution of membrane material along the pore walls. While the chemistry underlying the growth process remains unclear, the dependence of growth rate on current allows decoupling of the pore enlargement mechanism from the possibility of forming additional nanopores during the growth process, providing a practical method by which to rapidly enlarge a nanopore without risking opening a second nanopore.
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Affiliation(s)
- Chelsea Leung
- Department of Physics, University of Ottawa, Ottawa, Canada
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12
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Rozevsky Y, Gilboa T, van Kooten XF, Kobelt D, Huttner D, Stein U, Meller A. Quantification of mRNA Expression Using Single-Molecule Nanopore Sensing. ACS NANO 2020; 14:13964-13974. [PMID: 32930583 PMCID: PMC7510349 DOI: 10.1021/acsnano.0c06375] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
RNA quantification methods are broadly used in life science research and in clinical diagnostics. Currently, real-time reverse transcription polymerase chain reaction (RT-qPCR) is the most common analytical tool for RNA quantification. However, in cases of rare transcripts or inhibiting contaminants in the sample, an extensive amplification could bias the copy number estimation, leading to quantification errors and false diagnosis. Single-molecule techniques may bypass amplification but commonly rely on fluorescence detection and probe hybridization, which introduces noise and limits multiplexing. Here, we introduce reverse transcription quantitative nanopore sensing (RT-qNP), an RNA quantification method that involves synthesis and single-molecule detection of gene-specific cDNAs without the need for purification or amplification. RT-qNP allows us to accurately quantify the relative expression of metastasis-associated genes MACC1 and S100A4 in nonmetastasizing and metastasizing human cell lines, even at levels for which RT-qPCR quantification produces uncertain results. We further demonstrate the versatility of the method by adapting it to quantify severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA against a human reference gene. This internal reference circumvents the need for producing a calibration curve for each measurement, an imminent requirement in RT-qPCR experiments. In summary, we describe a general method to process complicated biological samples with minimal losses, adequate for direct nanopore sensing. Thus, harnessing the sensitivity of label-free single-molecule counting, RT-qNP can potentially detect minute expression levels of RNA biomarkers or viral infection in the early stages of disease and provide accurate amplification-free quantification.
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Affiliation(s)
- Yana Rozevsky
- Department
of Biomedical Engineering, The Technion—IIT, Haifa 32000, Israel
| | - Tal Gilboa
- Department
of Biomedical Engineering, The Technion—IIT, Haifa 32000, Israel
- Department
of Pathology, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts 02115, United States
- Wyss
Institute, Harvard University, Boston, Massachusetts 02115, United States
| | | | - Dennis Kobelt
- Experimental
and Clinical Research Center, Charité
Universitätsmedizin, Berlin 10117, Germany
- Max-Delbrück-Center
for Molecular Medicine in the Helmholtz Association, Berlin 13125, Germany
- German
Cancer Consortium, Heidelberg 69120, Germany
| | - Diana Huttner
- Department
of Biomedical Engineering, The Technion—IIT, Haifa 32000, Israel
| | - Ulrike Stein
- Experimental
and Clinical Research Center, Charité
Universitätsmedizin, Berlin 10117, Germany
- Max-Delbrück-Center
for Molecular Medicine in the Helmholtz Association, Berlin 13125, Germany
- German
Cancer Consortium, Heidelberg 69120, Germany
| | - Amit Meller
- Department
of Biomedical Engineering, The Technion—IIT, Haifa 32000, Israel
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13
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Fang S, Yin B, Xie W, Zhou D, Tang P, He S, Yuan J, Wang D. A novel dielectric breakdown apparatus for solid-state nanopore fabrication with transient high electric field. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2020; 91:093203. [PMID: 33003785 DOI: 10.1063/5.0024079] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Accepted: 09/07/2020] [Indexed: 06/11/2023]
Abstract
The dielectric breakdown used to fabricate solid-state nanopores has separated the device from capital-intensive industries and has been widely adopted by various research teams, but there are still problems with low production efficiency and uncertain location. In this work, based on the transient breakdown phenomenon of nanofilms, a new type of dielectric breakdown apparatus for nanopore fabrication is reported. It integrates both nano-manipulation technology and dielectric breakdown nanopore fabrication technology. The nanometer distance detection method and circuit are introduced in detail. The generation principle and procedures of the transient high electric field are explained step by step. The characterization of the nanopores shows that this apparatus can fabricate sub-2 nm nanopores at a pre-located position. Besides, the nanopore diameter can be easily adjusted by setting the transient high electric field value.
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Affiliation(s)
- Shaoxi Fang
- Chongqing Key Laboratory of Multi-scale Manufacturing Technology, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, People's Republic of China
| | - Bohua Yin
- Chongqing Key Laboratory of Multi-scale Manufacturing Technology, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, People's Republic of China
| | - Wanyi Xie
- Chongqing Key Laboratory of Multi-scale Manufacturing Technology, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, People's Republic of China
| | - Daming Zhou
- Chongqing Key Laboratory of Multi-scale Manufacturing Technology, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, People's Republic of China
| | - Peng Tang
- Chongqing Key Laboratory of Multi-scale Manufacturing Technology, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, People's Republic of China
| | - Shixuan He
- Chongqing Key Laboratory of Multi-scale Manufacturing Technology, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, People's Republic of China
| | - Jiahu Yuan
- Chongqing Key Laboratory of Multi-scale Manufacturing Technology, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, People's Republic of China
| | - Deqiang Wang
- Chongqing Key Laboratory of Multi-scale Manufacturing Technology, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, People's Republic of China
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14
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Hu R, Tong X, Zhao Q. Four Aspects about Solid-State Nanopores for Protein Sensing: Fabrication, Sensitivity, Selectivity, and Durability. Adv Healthc Mater 2020; 9:e2000933. [PMID: 32734703 DOI: 10.1002/adhm.202000933] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 07/11/2020] [Indexed: 12/27/2022]
Abstract
Solid-state nanopores are a mimic of innate biological nanopores embedded on lipid membranes. They are fabricated on thin suspended layers of synthetic materials that provide superior thermal, mechanical, chemical stability, and geometry flexibility. As their counterpart biological nanopores reach the goal of DNA sequencing and become commercial, solid-state nanopores thrive in aspects of protein sensing and have become an important research component for clinical diagnostic technologies. This review focuses on resistive pulse sensing modes, which are versatile for low-cost, portable sensing devices and summarizes four main aspects toward commercially available resistive pulse-based protein sensing techniques using solid-state nanopores. In each aspect of fabrication, sensitivity, selectivity, and durability, brief fundamentals are introduced and the challenges and improvements are discussed. The rapid advance of a practical technique requires greater multidisciplinary cooperation. The review aims at clarifying existing obstacles in solid-state nanopore based protein sensing, intriguing readers with existing solutions and finally encouraging multidisciplinary researchers to advance the development of this promising protein sensing methodology.
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Affiliation(s)
- Rui Hu
- State Key Lab for Mesoscopic Physics and Frontiers Science Center for Nano‐optoelectronics School of Physics Peking University Beijing 100871 China
| | - Xin Tong
- State Key Lab for Mesoscopic Physics and Frontiers Science Center for Nano‐optoelectronics School of Physics Peking University Beijing 100871 China
| | - Qing Zhao
- State Key Lab for Mesoscopic Physics and Frontiers Science Center for Nano‐optoelectronics School of Physics Peking University Beijing 100871 China
- Peking University Yangtze Delta Institute of Optoelectronics Nantong Jiangsu 226010 China
- Collaborative Innovation Center of Quantum Matter Beijing 100084 China
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15
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Zrehen A, Huttner D, Meller A. On-Chip Stretching, Sorting, and Electro-Optical Nanopore Sensing of Ultralong Human Genomic DNA. ACS NANO 2019; 13:14388-14398. [PMID: 31756076 PMCID: PMC6933818 DOI: 10.1021/acsnano.9b07873] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2019] [Accepted: 11/22/2019] [Indexed: 05/22/2023]
Abstract
Solid-state nanopore sensing of ultralong genomic DNA molecules has remained challenging, as the DNA must be controllably delivered by its leading end for efficient entry into the nanopore. Herein, we introduce a nanopore sensor device designed for electro-optical detection and sorting of ultralong (300+ kilobase pair) genomic DNA. The fluidic device, fabricated in-silicon and anodically bonded to glass, uses pressure-induced flow and an embedded pillar array for controllable DNA stretching and delivery. Extremely low concentrations (50 fM) and sample volumes (∼1 μL) of DNA can be processed. The low height profile of the device permits high numerical aperture, high magnification imaging of DNA molecules, which remain in focus over extended distances. We demonstrate selective DNA sorting based on sequence-specific nick translation labeling and imaging at high camera frame rates. Nanopores are fabricated directly in the assembled device by laser etching. We show that uncoiling and stretching of the ultralong DNA molecules permits efficient nanopore capture and threading, which is simultaneously and synchronously imaged and electrically measured. Furthermore, our technique provides key insights into the translocation behavior of ultralong DNA and promotes the development of all-in-one micro/nanofluidic platforms for nanopore sensing of biomolecules.
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Affiliation(s)
- Adam Zrehen
- Department
of Biomedical Engineering, Technion −
IIT, Haifa 32000, Israel
| | - Diana Huttner
- Department
of Biomedical Engineering, Technion −
IIT, Haifa 32000, Israel
| | - Amit Meller
- Department
of Biomedical Engineering, Technion −
IIT, Haifa 32000, Israel
- Russell
Berrie Nanotechnology Institute, Technion
− IIT, Haifa 32000, Israel
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16
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St-Denis T, Yazda K, Capaldi X, Bustamante J, Safari M, Miyahara Y, Zhang Y, Grutter P, Reisner W. An apparatus based on an atomic force microscope for implementing tip-controlled local breakdown. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2019; 90:123703. [PMID: 31893796 DOI: 10.1063/1.5129665] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Accepted: 11/30/2019] [Indexed: 06/10/2023]
Abstract
Solid-state nanopores are powerful tools for sensing of single biomolecules in solution. Fabrication of solid-state nanopores is still challenging, however; in particular, new methods are needed to facilitate the integration of pores with larger nanofluidic and electronic device architectures. We have developed the tip-controlled local breakdown (TCLB) approach, in which an atomic force microscope (AFM) tip is brought into contact with a silicon nitride membrane that is placed onto an electrolyte reservoir. The application of a voltage bias at the AFM tip induces a dielectric breakdown that leads to the formation of a nanopore at the tip position. In this work, we report on the details of the apparatus used to fabricate nanopores using the TCLB method, and we demonstrate the formation of nanopores with smaller, more controlled diameters using a current limiting circuit that zeroes the voltage upon pore formation. Additionally, we demonstrate the capability of TCLB to fabricate pores aligned to embedded topographical features on the membranes.
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Affiliation(s)
- T St-Denis
- Physics Department, McGill University, 3600 rue University, Montreal, Quebec H3A 2T8, Canada
| | - K Yazda
- Physics Department, McGill University, 3600 rue University, Montreal, Quebec H3A 2T8, Canada
| | - X Capaldi
- Physics Department, McGill University, 3600 rue University, Montreal, Quebec H3A 2T8, Canada
| | - J Bustamante
- Physics Department, McGill University, 3600 rue University, Montreal, Quebec H3A 2T8, Canada
| | - M Safari
- Norcada, 4548-99 Street NW, Edmonton, Alberta T6E 5H5, Canada
| | - Y Miyahara
- Physics Department, McGill University, 3600 rue University, Montreal, Quebec H3A 2T8, Canada
| | - Y Zhang
- Physics Department, McGill University, 3600 rue University, Montreal, Quebec H3A 2T8, Canada
| | - P Grutter
- Physics Department, McGill University, 3600 rue University, Montreal, Quebec H3A 2T8, Canada
| | - W Reisner
- Physics Department, McGill University, 3600 rue University, Montreal, Quebec H3A 2T8, Canada
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17
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Stable fabrication of a large nanopore by controlled dielectric breakdown in a high-pH solution for the detection of various-sized molecules. Sci Rep 2019; 9:13143. [PMID: 31511597 PMCID: PMC6739384 DOI: 10.1038/s41598-019-49622-y] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Accepted: 08/28/2019] [Indexed: 01/15/2023] Open
Abstract
For nanopore sensing of various-sized molecules with high sensitivity, the size of the nanopore should be adjusted according to the size of each target molecule. For solid-state nanopores, a simple and inexpensive nanopore fabrication method utilizing dielectric breakdown of a membrane is widely used. This method is suitable for fabricating a small nanopore. However, it suffers two serious problems when attempting to fabricate a large nanopore: the generation of multiple nanopores and the non-opening failure of a nanopore. In this study, we found that nanopore fabrication by dielectric breakdown of a SiN membrane under high-pH conditions (pH ≥ 11.3) could overcome these two problems and enabled the formation of a single large nanopore up to 40 nm in diameter within one minute. Moreover, the ionic-current blockades derived from streptavidin-labelled and non-labelled DNA passing through the fabricated nanopore were clearly distinguished. The current blockades caused by streptavidin-labelled DNA could be identified even when its concentration is 1% of the total DNA.
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18
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Spitzberg JD, Zrehen A, van Kooten XF, Meller A. Plasmonic-Nanopore Biosensors for Superior Single-Molecule Detection. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2019; 31:e1900422. [PMID: 30941823 DOI: 10.1002/adma.201900422] [Citation(s) in RCA: 86] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2019] [Revised: 02/19/2019] [Indexed: 05/26/2023]
Abstract
Plasmonic and nanopore sensors have separately received much attention for achieving single-molecule precision. A plasmonic "hotspot" confines and enhances optical excitation at the nanometer length scale sufficient to optically detect surface-analyte interactions. A nanopore biosensor actively funnels and threads analytes through a molecular-scale aperture, wherein they are interrogated by electrical or optical means. Recently, solid-state plasmonic and nanopore structures have been integrated within monolithic devices that address fundamental challenges in each of the individual sensing methods and offer complimentary improvements in overall single-molecule sensitivity, detection rates, dwell time and scalability. Here, the physical phenomena and sensing principles of plasmonic and nanopore sensing are summarized to highlight the novel complementarity in dovetailing these techniques for vastly improved single-molecule sensing. A literature review of recent plasmonic nanopore devices is then presented to delineate methods for solid-state fabrication of a range of hybrid device formats, evaluate the progress and challenges in the detection of unlabeled and labeled analyte, and assess the impact and utility of localized plasmonic heating. Finally, future directions and applications inspired by the present state of the art are discussed.
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Affiliation(s)
- Joshua D Spitzberg
- Department of Biomedical Engineering, Technion-IIT, Haifa, 32000, Israel
| | - Adam Zrehen
- Department of Biomedical Engineering, Technion-IIT, Haifa, 32000, Israel
| | | | - Amit Meller
- Department of Biomedical Engineering, Technion-IIT, Haifa, 32000, Israel
- Department of Biomedical Engineering, Boston University, Boston, MA, 02215, USA
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19
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Fabrication and practical applications of molybdenum disulfide nanopores. Nat Protoc 2019; 14:1130-1168. [PMID: 30903110 DOI: 10.1038/s41596-019-0131-0] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2018] [Accepted: 01/04/2019] [Indexed: 01/01/2023]
Abstract
Among the different developed solid-state nanopores, nanopores constructed in a monolayer of molybdenum disulfide (MoS2) stand out as powerful devices for single-molecule analysis or osmotic power generation. Because the ionic current through a nanopore is inversely proportional to the thickness of the pore, ultrathin membranes have the advantage of providing relatively high ionic currents at very small pore sizes. This increases the signal generated during translocation of biomolecules and improves the nanopores' efficiency when used for desalination or reverse electrodialysis applications. The atomic thickness of MoS2 nanopores approaches the inter-base distance of DNA, creating a potential candidate for DNA sequencing. In terms of geometry, MoS2 nanopores have a well-defined vertical profile due to their atomic thickness, which eliminates any unwanted effects associated with uneven pore profiles observed in other materials. This protocol details all the necessary procedures for the fabrication of solid-state devices. We discuss different methods for transfer of monolayer MoS2, different approaches for the creation of nanopores, their applicability in detecting DNA translocations and the analysis of translocation data through open-source programming packages. We present anticipated results through the application of our nanopores in DNA translocations and osmotic power generation. The procedure comprises four parts: fabrication of devices (2-3 d), transfer of MoS2 and cleaning procedure (24 h), the creation of nanopores within MoS2 (30 min) and performing DNA translocations (2-3 h). We anticipate that our protocol will enable large-scale manufacturing of single-molecule-analysis devices as well as next-generation DNA sequencing.
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20
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Roshan KA, Tang Z, Guan W. High fidelity moving Z-score based controlled breakdown fabrication of solid-state nanopore. NANOTECHNOLOGY 2019; 30:095502. [PMID: 30523901 DOI: 10.1088/1361-6528/aaf48e] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
We investigate the current transport characteristics in the electrolyte-dielectric-electrolyte structure commonly used in the in situ controlled breakdown (CBD) fabrication of solid-state nanopores. It is found that the stochastic breakdown process could lead to fidelity issues of false positives (an incorrect indication of a true nanopore formation) and false negatives (inability to detect initial nanopore formation). Robust and deterministic detection of initial physical breakdown to alleviate false positives and false negatives is critical for precise nanopore size control. To this end, we report a high fidelity moving Z-score method based CBD fabrication of solid-state nanopore. We demonstrate 100% success rate of realizing the initial nanopore conductance of 3 ± 1 nS (corresponds to size of 1.7 ± 0.6 nm) regardless of the dielectric membrane characteristics. Our study also elucidates the Joule heating is the dominant mechanism for electric field-based nanopore enlargement. Single DNA molecule sensing using nanopores fabricated by this method was successfully demonstrated. We anticipate the moving Z-score based CBD method could enable broader access to the solid state nanopore-based single molecule analysis.
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Affiliation(s)
- Kamyar Akbari Roshan
- Department of Electrical Engineering, Pennsylvania State University, University Park 16802, United States of America
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21
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Yamazaki H, Hu R, Zhao Q, Wanunu M. Photothermally Assisted Thinning of Silicon Nitride Membranes for Ultrathin Asymmetric Nanopores. ACS NANO 2018; 12:12472-12481. [PMID: 30457833 DOI: 10.1021/acsnano.8b06805] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Sculpting solid-state materials at the nanoscale is an important step in the manufacturing of numerous types of sensor devices, in particular solid-state nanopore sensors. Here we present mechanistic insight into laser-induced thinning of low-stress silicon nitride (SiN x) membranes and films. In a recent study, we observed that focusing a visible wavelength laser beam on a SiN x membrane results in efficient localized heating, and we used this effect to control temperature at a solid-state nanopore sensor. A side-effect of the observed heating was that the pores expand/degrade under prolonged high-power illumination, prompting us to study the mechanism of this etching process. We find that SiN x can be etched under exposure to light of ∼107 W/cm2 average intensity, with etch rates that are influenced by the supporting electrolyte. Combining this controlled etching with dielectric breakdown, an electrokinetic process for making pores, nanopores of arbitrary dimensions as small as 1-2 nm in diameter and thickness can easily be fabricated. Evidence gathered from biomolecule-pore interactions suggests that the pore geometries obtained using this method are more funnel-like, rather than hourglass-shaped. Refined control over pore dimensions can expand the range of applications of solid-state nanopores, for example, biopolymer sequencing and detection of specific biomarkers.
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Affiliation(s)
- Hirohito Yamazaki
- Department of Physics , Northeastern University , Boston , Massachusetts 02115 , United States
| | - Rui Hu
- State Key Laboratory for Mesoscopic Physics, School of Physics , Peking University , Beijing 100871 , People's Republic of China
| | - Qing Zhao
- State Key Laboratory for Mesoscopic Physics, School of Physics , Peking University , Beijing 100871 , People's Republic of China
| | - Meni Wanunu
- Department of Physics , Northeastern University , Boston , Massachusetts 02115 , United States
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22
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Ying C, Houghtaling J, Eggenberger OM, Guha A, Nirmalraj P, Awasthi S, Tian J, Mayer M. Formation of Single Nanopores with Diameters of 20-50 nm in Silicon Nitride Membranes Using Laser-Assisted Controlled Breakdown. ACS NANO 2018; 12:11458-11470. [PMID: 30335956 DOI: 10.1021/acsnano.8b06489] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Nanopores with diameters from 20 to 50 nm in silicon nitride (SiN x) windows are useful for single-molecule studies of globular macromolecules. While controlled breakdown (CBD) is gaining popularity as a method for fabricating nanopores with reproducible size control and broad accessibility, attempts to fabricate large nanopores with diameters exceeding ∼20 nm via breakdown often result in undesirable formation of multiple nanopores in SiN x membranes. To reduce the probability of producing multiple pores, we combined two strategies: laser-assisted breakdown and controlled pore enlargement by limiting the applied voltage. Based on laser power-dependent increases in nanopore conductance upon illumination and on the absence of an effect of ionic strength on the ratio between the nanopore conductance before and after laser illumination, we suggest that the increased rate of controlled breakdown results from laser-induced heating. Moreover, we demonstrate that conductance values before and after coating the nanopores with a fluid lipid bilayer can indicate fabrication of a single nanopore versus multiple nanopores. Complementary flux measurements of Ca2+ through the nanopore typically confirmed assessments of single or multiple nanopores that we obtained using the coating method. Finally, we show that thermal annealing of CBD pores significantly increased the success rate of coating and reduced the current noise before and after lipid coating. We characterize the geometry of these nanopores by analyzing individual resistive pulses produced by translocations of spherical proteins and demonstrate the usefulness of these nanopores for estimating the approximate molecular shape of IgG proteins.
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Affiliation(s)
- Cuifeng Ying
- Adolphe Merkle Institute , University of Fribourg , Chemin des Verdiers 4 , CH-1700 Fribourg , Switzerland
| | - Jared Houghtaling
- Adolphe Merkle Institute , University of Fribourg , Chemin des Verdiers 4 , CH-1700 Fribourg , Switzerland
- Department of Biomedical Engineering , University of Michigan , 2200 Bonisteel Boulevard , Ann Arbor , Michigan 48109 , United States
| | - Olivia M Eggenberger
- Adolphe Merkle Institute , University of Fribourg , Chemin des Verdiers 4 , CH-1700 Fribourg , Switzerland
| | - Anirvan Guha
- Adolphe Merkle Institute , University of Fribourg , Chemin des Verdiers 4 , CH-1700 Fribourg , Switzerland
| | - Peter Nirmalraj
- Adolphe Merkle Institute , University of Fribourg , Chemin des Verdiers 4 , CH-1700 Fribourg , Switzerland
| | - Saurabh Awasthi
- Adolphe Merkle Institute , University of Fribourg , Chemin des Verdiers 4 , CH-1700 Fribourg , Switzerland
| | - Jianguo Tian
- Key Laboratory of Weak-Light Nonlinear Photonics, Ministry of Education, School of Physics , Nankai University , Tianjin 300071 , China
| | - Michael Mayer
- Adolphe Merkle Institute , University of Fribourg , Chemin des Verdiers 4 , CH-1700 Fribourg , Switzerland
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23
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Wang R, Gilboa T, Song J, Huttner D, Grinstaff MW, Meller A. Single-Molecule Discrimination of Labeled DNAs and Polypeptides Using Photoluminescent-Free TiO 2 Nanopores. ACS NANO 2018; 12:11648-11656. [PMID: 30372037 DOI: 10.1021/acsnano.8b07055] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Multicolor fluorescence substantially expands the sensing capabilities of nanopores by complementing or substituting the resistive pulsing signals. However, to date single-fluorophore detection in multiple color channels has proven to be challenging primarily due to high photoluminescence (PL) emanating from the silicon nitride (SiN x) membrane. We hypothesize that the high bandgap of titanium oxide (TiO2) would eliminate the PL background when used as a substrate for a nanopore, and hence enable individual fluorophore sensing during the fast passage of biomolecules through the pore. Herein, we introduce a method for fabricating locally supported, free-standing, TiO2 membranes, in which solid-state nanopores can be readily drilled. These devices produce essentially no PL in the blue-to-red visible spectral range, even when excited by multiple lasers simultaneously. At the same time, the TiO2 nanopores exhibit low electrical noise comparable with standard SiN x devices. Importantly, the optical signal-to-background ratio (SBR) in single-molecule sensing is improved by an order of magnitude, enabling the differentiation among labeled DNA molecules of similar length based solely on their labeling scheme. Finally, the increased SBR of the TiO2 devices allows detection of single fluorophores conjugated to the lysine or cysteine residues of short polypeptides, thus introducing the possibility for optical based peptide/protein discrimination in nanopores.
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Affiliation(s)
- Rui Wang
- Department of Biomedical Engineering, Technion-IIT , Haifa , 32000 , Israel
| | - Tal Gilboa
- Department of Biomedical Engineering, Technion-IIT , Haifa , 32000 , Israel
| | - Jiaxi Song
- Department of Biomedical Engineering , Boston University , Boston , Massachusetts 02215 , United States
| | - Diana Huttner
- Department of Biomedical Engineering, Technion-IIT , Haifa , 32000 , Israel
| | - Mark W Grinstaff
- Department of Biomedical Engineering , Boston University , Boston , Massachusetts 02215 , United States
| | - Amit Meller
- Department of Biomedical Engineering, Technion-IIT , Haifa , 32000 , Israel
- Department of Biomedical Engineering , Boston University , Boston , Massachusetts 02215 , United States
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24
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Yanagi I, Hamamura H, Akahori R, Takeda KI. Two-step breakdown of a SiN membrane for nanopore fabrication: Formation of thin portion and penetration. Sci Rep 2018; 8:10129. [PMID: 29973672 PMCID: PMC6031669 DOI: 10.1038/s41598-018-28524-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Accepted: 06/22/2018] [Indexed: 11/09/2022] Open
Abstract
For the nanopore sensing of various large molecules, such as probe-labelled DNA and antigen-antibody complexes, the nanopore size has to be customized for each target molecule. The recently developed nanopore fabrication method utilizing dielectric breakdown of a membrane is simple and quite inexpensive, but it is somewhat unsuitable for the stable fabrication of a single large nanopore due to the risk of generating multiple nanopores. To overcome this bottleneck, we propose a new technique called “two-step breakdown” (TSB). In the first step of TSB, a local conductive thin portion (not a nanopore) is formed in the membrane by dielectric breakdown. In the second step, the created thin portion is penetrated by voltage pulses whose polarity is opposite to the polarity of the voltage used in the first step. By applying TSB to a 20-nm-thick SiN membrane, a single nanopore with a diameter of 21–26 nm could be fabricated with a high yield of 83%.
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Affiliation(s)
- Itaru Yanagi
- Hitachi Ltd., Research & Development Group, Center for Technology Innovation - Healthcare, 1-280, Higashi-koigakubo, Kokubunji, Tokyo, 185-8603, Japan.
| | - Hirotaka Hamamura
- Hitachi Ltd., Research & Development Group, Center for Technology Innovation - Healthcare, 1-280, Higashi-koigakubo, Kokubunji, Tokyo, 185-8603, Japan
| | - Rena Akahori
- Hitachi Ltd., Research & Development Group, Center for Technology Innovation - Healthcare, 1-280, Higashi-koigakubo, Kokubunji, Tokyo, 185-8603, Japan
| | - Ken-Ichi Takeda
- Hitachi Ltd., Research & Development Group, Center for Technology Innovation - Healthcare, 1-280, Higashi-koigakubo, Kokubunji, Tokyo, 185-8603, Japan
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25
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Optically-Monitored Nanopore Fabrication Using a Focused Laser Beam. Sci Rep 2018; 8:9765. [PMID: 29950607 PMCID: PMC6021433 DOI: 10.1038/s41598-018-28136-z] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Accepted: 06/18/2018] [Indexed: 12/25/2022] Open
Abstract
Solid-state nanopores (ssNPs) are extremely versatile single-molecule sensors and their potential have been established in numerous biomedical applications. However, the fabrication of ssNPs remains the main bottleneck to their widespread use. Herein, we introduce a rapid and localizable ssNPs fabrication method based on feedback-controlled optical etching. We show that a focused blue laser beam irreversibly etches silicon nitride (SiNx) membranes in solution. Furthermore, photoluminescence (PL) emitted from the SiNx is used to monitor the etching process in real-time, hence permitting rate adjustment. Transmission electron microscopy (TEM) images of the etched area reveal an inverted Gaussian thickness profile, corresponding to the intensity point spread function of the laser beam. Continued laser exposure leads to the opening of a nanopore, which can be controlled to reproducibly fabricate nanopores of different sizes. The optically-formed ssNPs exhibit electrical noise on par with TEM-drilled pores, and translocate DNA and proteins readily. Notably, due to the localized thinning, the laser-drilled ssNPs exhibit highly suppressed background PL and improved spatial resolution. Given the total control over the nanopore position, this easily implemented method is ideally suited for electro-optical sensing and opens up the possibility of fabricating large nanopore arrays in situ.
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26
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Verschueren DV, Yang W, Dekker C. Lithography-based fabrication of nanopore arrays in freestanding SiN and graphene membranes. NANOTECHNOLOGY 2018; 29:145302. [PMID: 29384130 PMCID: PMC5997186 DOI: 10.1088/1361-6528/aaabce] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
We report a simple and scalable technique for the fabrication of nanopore arrays on freestanding SiN and graphene membranes based on electron-beam lithography and reactive ion etching. By controlling the dose of the single-shot electron-beam exposure, circular nanopores of any size down to 16 nm in diameter can be fabricated in both materials at high accuracy and precision. We demonstrate the sensing capabilities of these nanopores by translocating dsDNA through pores fabricated using this method, and find signal-to-noise characteristics on par with transmission-electron-microscope-drilled nanopores. This versatile lithography-based approach allows for the high-throughput manufacturing of nanopores and can in principle be used on any substrate, in particular membranes made out of transferable two-dimensional materials.
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Wang Y, Yan S, Zhang P, Zeng Z, Zhao D, Wang J, Chen H, Huang S. Osmosis-Driven Motion-Type Modulation of Biological Nanopores for Parallel Optical Nucleic Acid Sensing. ACS APPLIED MATERIALS & INTERFACES 2018; 10:7788-7797. [PMID: 29431423 DOI: 10.1021/acsami.7b18347] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Recent developments in nanopore sequencing have inspired new concepts in precision medicine but limited in throughput. By optically encoding calcium flux from an array of nanopores, parallel measurements from hundreds of nanopores were reported, while lateral drifts of biological nanopores set obstacles for signal processing. In this paper, optical single-channel recording (oSCR) serves to track nanopores with high precision and a general principle of nanopore motion kinetics is quantitatively investigated. By finely adjusting the osmosis-oriented interactions between the lipid/substrate interfaces, motions of nanopores could be controllably restricted. Improved signal-to-noise ratio is observed from motion-restricted nanopores, which is experimentally demonstrated. To systematically evaluate oSCR with asymmetric salt concentrations, a finite element method simulation is established. oSCR with an array of immobilized nanopores suggests new strategies for sequencing DNA by microscopic imaging in high throughput and is widely applicable to the investigation of other transmembrane proteins.
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Affiliation(s)
| | | | | | - Zidao Zeng
- Department of Chemistry , University of Pittsburgh , 219 Parkman Avenue , Pittsburgh , Pennsylvania 15260 , United States
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Fabrication of multiple nanopores in a SiN x membrane via controlled breakdown. Sci Rep 2018; 8:1234. [PMID: 29352158 PMCID: PMC5775244 DOI: 10.1038/s41598-018-19450-7] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Accepted: 01/02/2018] [Indexed: 12/13/2022] Open
Abstract
This paper reports a controlled breakdown (CBD) method to fabricate multiple nanopores in a silicon nitride (SiNx) membrane with control over both nanopore count and nanopore diameter. Despite the stochastic process of the breakdown, we found that the nanopores created via CBD, tend to be of the same diameter. We propose a membrane resistance model to explain and control the multiple nanopores forming in the membrane. We prove that the membrane resistance can reflect the number of nanopores in the membrane and that the diameter of the nanopores is controlled by the exposure time and strength of the electric field. This controllable multiple nanopore formation via CBD avoids the utilization of complicated instruments and time-intensive manufacturing. We anticipate CBD has the potential to become a nanopore fabrication technique which, integrated into an optical setup, could be used as a high-throughput and multichannel characterization technique.
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