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Leyva–Pérez A, Bilanin C, Bacic M, Greco R. Acid and base water coexists in a micro–structured ionic liquid and catalyzes organic reactions in one–pot. ChemCatChem 2022. [DOI: 10.1002/cctc.202200557] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Antonio Leyva–Pérez
- CSIC Instituto de Tecnologia Quimica Avda. de los Naranjos S/N 46022 Valencia SPAIN
| | - Cristina Bilanin
- Instituto de Tecnologia Quimica Instituto de Tecnologia Quimica SPAIN
| | - Matea Bacic
- Instituto de Tecnologia Quimica Instituto de Tecnologia Quimica SPAIN
| | - Rossella Greco
- Instituto de Tecnologia Quimica Instituto de Tecnologia Quimica SPAIN
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2
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Chen ZP, Yang P, Yang ZZ, Chai YQ, Yuan R, Zhuo Y, Liang WB. One-Step Digital Droplet Auto-Catalytic Nucleic Acid Amplification with High-Throughput Fluorescence Imaging and Droplet Tracking Computation. Anal Chem 2022; 94:9166-9175. [PMID: 35708271 DOI: 10.1021/acs.analchem.2c01754] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Digital droplet technology has emerged as a powerful new tool for biomarker analysis. Temperature cycling, enzymes, and off-chip processes are, nevertheless, always required. Herein, we constructed a digital droplet auto-catalytic hairpin assembly (ddaCHA) microfluidic system to achieve digital quantification of single-molecule microRNA (miRNA). The designed continuous chip integrates droplet generation, incubation, and fluorescence imaging on the chip, avoiding the requirement for extra droplet re-collection and heating operations. Clearly, the digital readout was obtained by partitioning miRNA into many individual pL-sized small droplets in which the target molecule is either present ("positive") or absent ("negative"). Importantly, the suggested enzyme-free auto-catalytic hairpin assembly (aCHA) in droplets successfully mitigated the effects of the external environment and thermal cycling on droplets, and its reaction rate is significantly superior to that of traditional CHA. We got excellent sensitivity with a linear correlation from 1 pM to 10 nM and a detection limit of 0.34 pM in the fluorescence spectrum section, as well as high selectivity to other miRNAs. Furthermore, the minimum target concentration could be reduced to 10 fM based on the high-throughput tracking computation of fluorescent droplets with a self-developed Python script, and the fluorescence intensity distribution agreed well with the theoretical value, demonstrating that it is feasible to detect miRNA efficiently and accurately, which has great potential applications in clinical diagnostics and biochemical research.
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Affiliation(s)
- Zhao-Peng Chen
- Key Laboratory of Luminescence Analysis and Molecular Sensing (Southwest University), Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China
| | - Peng Yang
- Key Laboratory of Luminescence Analysis and Molecular Sensing (Southwest University), Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China
| | - Ze-Zhou Yang
- Key Laboratory of Luminescence Analysis and Molecular Sensing (Southwest University), Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China
| | - Ya-Qin Chai
- Key Laboratory of Luminescence Analysis and Molecular Sensing (Southwest University), Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China
| | - Ruo Yuan
- Key Laboratory of Luminescence Analysis and Molecular Sensing (Southwest University), Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China
| | - Ying Zhuo
- Key Laboratory of Luminescence Analysis and Molecular Sensing (Southwest University), Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China
| | - Wen-Bin Liang
- Key Laboratory of Luminescence Analysis and Molecular Sensing (Southwest University), Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China
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Naiserová M, Vysloužil J, Kubová K, Holická M, Vetchý D, Mašek J, Mašková E. Use of droplet-based microfluidic techniques in the preparation of microparticles. CESKA A SLOVENSKA FARMACIE : CASOPIS CESKE FARMACEUTICKE SPOLECNOSTI A SLOVENSKE FARMACEUTICKE SPOLECNOSTI 2021; 70:155–163. [PMID: 34875837 DOI: 10.5817/csf2021-5-155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Microparticles are widely used in myriad fields such as pharmaceuticals, foods, cosmetics, and other industrial fields. Compared with traditional methods for synthesizing microparticles, microfluidic techniques provide very powerful platforms for creating highly controllable emulsion droplets as templates for fabricating uniform microparticles with advanced structures and functions. Microfluidic techniques can generate emulsion droplets with precisely controlled size, shape, and composition. A more precise preparation process brings an effective tool to control the release profile of the drug and introduces an easily accessible reproducibility. The paper gives information about basic droplet-based set-ups and examples of attainable microparticle types preparable by this method.
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Arter WE, Yusim Y, Peter Q, Taylor CG, Klenerman D, Keyser UF, Knowles TPJ. Digital Sensing and Molecular Computation by an Enzyme-Free DNA Circuit. ACS NANO 2020; 14:5763-5771. [PMID: 32293175 DOI: 10.1021/acsnano.0c00628] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
DNA circuits form the basis of programmable molecular systems capable of signal transduction and algorithmic computation. Some classes of molecular programs, such as catalyzed hairpin assembly, enable isothermal, enzyme-free signal amplification. However, current detection limits in DNA amplification circuits are modest, as sensitivity is inhibited by signal leakage resulting from noncatalyzed background reactions inherent to the noncovalent system. Here, we overcome this challenge by optimizing a catalyzed hairpin assembly for single-molecule sensing in a digital droplet assay. Furthermore, we demonstrate digital reporting of DNA computation at the single-molecule level by employing ddCHA as a signal transducer for simple DNA logic gates. By facilitating signal transduction of molecular computation at pM concentration, our approach can improve processing density by a factor of 104 relative to conventional DNA logic gates. More broadly, we believe that digital molecular computing will broaden the scope and efficacy of isothermal amplification circuits within DNA computing, biosensing, and signal amplification in general.
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Affiliation(s)
- William E Arter
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, United Kingdom
- Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge, CB3 0HE, United Kingdom
| | - Yuriy Yusim
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, United Kingdom
| | - Quentin Peter
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, United Kingdom
| | - Christopher G Taylor
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, United Kingdom
| | - David Klenerman
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, United Kingdom
| | - Ulrich F Keyser
- Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge, CB3 0HE, United Kingdom
| | - Tuomas P J Knowles
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, United Kingdom
- Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge, CB3 0HE, United Kingdom
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5
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Sun J, Warden AR, Ding X. Recent advances in microfluidics for drug screening. BIOMICROFLUIDICS 2019; 13:061503. [PMID: 31768197 PMCID: PMC6870548 DOI: 10.1063/1.5121200] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Accepted: 11/07/2019] [Indexed: 05/03/2023]
Abstract
With ever increasing drug resistance and emergence of new diseases, demand for new drug development is at an unprecedented urgency. This fact has led to extensive recent efforts to develop new drugs and novel techniques for efficient drug screening. However, new drug development is commonly hindered by cost and time span. Thus, developing more accessible, cost-effective methods for drug screening is necessary. Compared with conventional drug screening methods, a microfluidic-based system has superior advantages in sample consumption, reaction time, and cost of the operation. In this paper, the advantages of microfluidic technology in drug screening as well as the critical factors for device design are described. The strategies and applications of microfluidics for drug screening are reviewed. Moreover, current limitations and future prospects for a drug screening microdevice are also discussed.
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Affiliation(s)
- Jiahui Sun
- State Key Laboratory of Oncogenes and Related Genes, Institute for
Personalized Medicine and School of Biomedical Engineering, Shanghai Jiao Tong
University, Shanghai 200030, China
| | - Antony R. Warden
- State Key Laboratory of Oncogenes and Related Genes, Institute for
Personalized Medicine and School of Biomedical Engineering, Shanghai Jiao Tong
University, Shanghai 200030, China
| | - Xianting Ding
- State Key Laboratory of Oncogenes and Related Genes, Institute for
Personalized Medicine and School of Biomedical Engineering, Shanghai Jiao Tong
University, Shanghai 200030, China
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7
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Liu C, Xu X, Li B, Situ B, Pan W, Hu Y, An T, Yao S, Zheng L. Single-Exosome-Counting Immunoassays for Cancer Diagnostics. NANO LETTERS 2018; 18:4226-4232. [PMID: 29888919 DOI: 10.1021/acs.nanolett.8b01184] [Citation(s) in RCA: 241] [Impact Index Per Article: 40.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Exosomes shed by tumor cells have been recognized as promising biomarkers for cancer diagnostics due to their unique composition and functions. Quantification of low concentrations of specific exosomes present in very small volumes of clinical samples may be used for noninvasive cancer diagnosis and prognosis. We developed an immunosorbent assay for digital qualification of target exosomes using droplet microfluidics. The exosomes were immobilized on magnetic microbeads through sandwich ELISA complexes tagged with an enzymatic reporter that produces a fluorescent signal. The constructed beads were further isolated and encapsulated into a sufficient number of droplets to ensure only a single bead was encapsulated in a droplet. Our droplet-based single-exosome-counting enzyme-linked immunoassay (droplet digital ExoELISA) approach enables absolute counting of cancer-specific exosomes to achieve unprecedented accuracy. We were able to achieve a limit of detection (LOD) down to 10 enzyme-labeled exosome complexes per microliter (∼10-17 M). We demonstrated the application of the droplet digital ExoELISA platform in quantitative detection of exosomes in plasma samples directly from breast cancer patients. We believe our approach may have the potential for early diagnosis of cancer and accelerate the discovery of cancer exosomal biomarkers for clinical diagnosis.
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Affiliation(s)
- Chunchen Liu
- Department of Mechanical and Aerospace Engineering , The Hong Kong University of Science and Technology , Hong Kong , China
| | - Xiaonan Xu
- Department of Mechanical and Aerospace Engineering , The Hong Kong University of Science and Technology , Hong Kong , China
| | | | | | | | - Yu Hu
- Department of Mechanical and Aerospace Engineering , The Hong Kong University of Science and Technology , Hong Kong , China
| | | | - Shuhuai Yao
- Department of Mechanical and Aerospace Engineering , The Hong Kong University of Science and Technology , Hong Kong , China
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Regnault C, Dheeman DS, Hochstetter A. Microfluidic Devices for Drug Assays. High Throughput 2018; 7:E18. [PMID: 29925804 PMCID: PMC6023517 DOI: 10.3390/ht7020018] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Revised: 06/07/2018] [Accepted: 06/13/2018] [Indexed: 12/14/2022] Open
Abstract
In this review, we give an overview of the current state of microfluidic-based high-throughput drug assays. In this highly interdisciplinary research field, various approaches have been applied to high-throughput drug screening, including microtiter plate, droplets microfluidics as well as continuous flow, diffusion and concentration gradients-based microfluidic drug assays. Therefore, we reviewed over 100 recent publications in the field and sorted them according to their microfluidic approach. As a result, we are showcasing, comparing and discussing broadly applied approaches as well as singular promising ones that might contribute to shaping the future of this field.
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Affiliation(s)
- Clément Regnault
- Wellcome Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8TA, UK.
| | - Dharmendra S Dheeman
- Wellcome Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8TA, UK.
| | - Axel Hochstetter
- Division of Biomedical Engineering, School of Engineering, University of Glasgow, Glasgow G12 8LT, UK.
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Guo XL, Wei Y, Lou Q, Zhu Y, Fang Q. Manipulating Femtoliter to Picoliter Droplets by Pins for Single Cell Analysis and Quantitative Biological Assay. Anal Chem 2018; 90:5810-5817. [PMID: 29648445 DOI: 10.1021/acs.analchem.8b00343] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Herein, we developed an automated and flexible system for performing miniaturized liquid-liquid reactions and assays in the femtoliter to picoliter range, by combining the contact printing and the droplet-based microfluidics techniques. The system mainly consisted of solid pins and an oil-covered hydrophilic micropillar array chip fixed on an automated x- y- z translation stage. A novel droplet manipulation mode called "dipping-depositing-moving" (DDM) was proposed, which was based on the programmable combination of three basic operations, dipping liquids and depositing liquids with the solid pins and moving the two-dimensional oil-covered hydrophilic pillar microchip. With the DDM mode, flexible generation and manipulation of small droplets with volumes down to 179 fL could be achieved. For overcoming the scale phenomenon specially appeared in picoliter-scale droplets, we used a design of water moat to protect the femtoliter to picoliter droplets from volume loss through the cover oil during the droplet generation, manipulation, reaction and assay processes. Moreover, we also developed a precise quantitative method, quantitative droplet dilution method, to accurately measure the volumes of femtoliter to picoliter droplets. To demonstrate its feasibility and adaptability, we applied the present system in the determination of kinetics parameter for matrix metalloproteinases (MMP-9) in 1.81 pL reactors and the measurement the activity of β-galactosidase in single cells (HepG2 cells) in picoliter droplet array. The ultrasmall volumes of the droplet reactors avoided the excessive dilution to the reaction solutions and enabled the highly sensitive measurement of enzyme activity in the single cell level.
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Affiliation(s)
- Xiao-Li Guo
- Institute of Microanalytical Systems, Department of Chemistry and Innovation Center for Cell Signaling Network , Zhejiang University , Hangzhou , 310058 , China
| | - Yan Wei
- Institute of Microanalytical Systems, Department of Chemistry and Innovation Center for Cell Signaling Network , Zhejiang University , Hangzhou , 310058 , China
| | - Qi Lou
- Institute of Microanalytical Systems, Department of Chemistry and Innovation Center for Cell Signaling Network , Zhejiang University , Hangzhou , 310058 , China
| | - Ying Zhu
- Institute of Microanalytical Systems, Department of Chemistry and Innovation Center for Cell Signaling Network , Zhejiang University , Hangzhou , 310058 , China
| | - Qun Fang
- Institute of Microanalytical Systems, Department of Chemistry and Innovation Center for Cell Signaling Network , Zhejiang University , Hangzhou , 310058 , China
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Axt B, Hsieh YF, Nalayanda D, Wang TH. Impedance feedback control of microfluidic valves for reliable post processing combinatorial droplet injection. Biomed Microdevices 2018; 19:61. [PMID: 28681238 DOI: 10.1007/s10544-017-0203-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Droplet microfluidics has found use in many biological assay applications as a means of high-throughput sample processing. One of the challenges of the technology, however, is the ability to control and merge droplets on-demand as they flow through the microdevices. It is in the interest of developing lab-on-chip devices to be able to combinatorically program additive mixing steps for more complex multistep and multiplex assays. Existing technologies to merge droplets are either passive in nature or require highly predictable droplet movement for feedforward control, making them vulnerable to errors during high throughput operation. In this paper, we describe and demonstrate a microfluidic valve-based device for the purpose of combinatorial droplet injection at any stage in a multistep assay. Microfluidic valves are used to robustly control fluid flow, droplet generation, and droplet mixing in the device on-demand, while on-chip impedance measurements taken in real time are used as feedback to accurately time the droplet injections. The presented system is contrasted to attempts without feedback, and is shown to be 100% reliable over long durations. Additionally, content detection and discretionary injections are explored and successfully executed.
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Affiliation(s)
- Brant Axt
- Department of Biomedical Engineering, Johns Hopkins University, 3400 N. Charles Street, Clark Hall 118B, Baltimore, MD, 21218, USA
| | - Yi-Fan Hsieh
- Department of Mechanical Engineering, Johns Hopkins University, 3400 N. Charles Street, Shaffer Hall 200A, Baltimore, MD, 21218, USA
| | - Divya Nalayanda
- Department of Biomedical Engineering, Johns Hopkins University, 3400 N. Charles Street, Clark Hall 118B, Baltimore, MD, 21218, USA
| | - Tza-Huei Wang
- Department of Biomedical Engineering, Johns Hopkins University, 3400 N. Charles Street, Clark Hall 118B, Baltimore, MD, 21218, USA. .,Department of Mechanical Engineering, Johns Hopkins University, 3400 N. Charles Street, Shaffer Hall 200A, Baltimore, MD, 21218, USA.
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11
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Mair P, Gielen F, Hollfelder F. Exploring sequence space in search of functional enzymes using microfluidic droplets. Curr Opin Chem Biol 2017; 37:137-144. [PMID: 28390246 DOI: 10.1016/j.cbpa.2017.02.018] [Citation(s) in RCA: 68] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2017] [Revised: 02/08/2017] [Accepted: 02/15/2017] [Indexed: 12/21/2022]
Abstract
Screening of enzyme mutants in monodisperse picoliter compartments, generated at kilohertz speed in microfluidic devices, is coming of age. After a decade of proof-of-principle experiments, workflows have emerged that combine existing microfluidic modules to assay reaction progress quantitatively and yield improved enzymes. Recent examples of the screening of libraries of randomised proteins and from metagenomic sources suggest that this approach is not only faster and cheaper, but solves problems beyond the feasibility scope of current methodologies. The establishment of new assays in this format - so far covering hydrolases, aldolases, polymerases and dehydrogenases - will enable the exploration of sequence space for new catalysts of natural and non-natural chemical transformations.
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Affiliation(s)
- Philip Mair
- Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge CB2 1GA, UK
| | - Fabrice Gielen
- Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge CB2 1GA, UK; Living Systems Institute, University of Exeter, Stocker Road, Exeter EX4 4QD, UK
| | - Florian Hollfelder
- Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge CB2 1GA, UK.
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12
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Huang L, Bian S, Cheng Y, Shi G, Liu P, Ye X, Wang W. Microfluidics cell sample preparation for analysis: Advances in efficient cell enrichment and precise single cell capture. BIOMICROFLUIDICS 2017; 11:011501. [PMID: 28217240 PMCID: PMC5303167 DOI: 10.1063/1.4975666] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Accepted: 01/24/2017] [Indexed: 05/03/2023]
Abstract
Single cell analysis has received increasing attention recently in both academia and clinics, and there is an urgent need for effective upstream cell sample preparation. Two extremely challenging tasks in cell sample preparation-high-efficiency cell enrichment and precise single cell capture-have now entered into an era full of exciting technological advances, which are mostly enabled by microfluidics. In this review, we summarize the category of technologies that provide new solutions and creative insights into the two tasks of cell manipulation, with a focus on the latest development in the recent five years by highlighting the representative works. By doing so, we aim both to outline the framework and to showcase example applications of each task. In most cases for cell enrichment, we take circulating tumor cells (CTCs) as the target cells because of their research and clinical importance in cancer. For single cell capture, we review related technologies for many kinds of target cells because the technologies are supposed to be more universal to all cells rather than CTCs. Most of the mentioned technologies can be used for both cell enrichment and precise single cell capture. Each technology has its own advantages and specific challenges, which provide opportunities for researchers in their own area. Overall, these technologies have shown great promise and now evolve into real clinical applications.
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Affiliation(s)
- Liang Huang
- State Key Laboratory of Precision Measurement Technology and Instrument, Department of Precision Instrument, Tsinghua University , Beijing, China
| | - Shengtai Bian
- Department of Biomedical Engineering, Tsinghua University , Beijing, China
| | - Yinuo Cheng
- State Key Laboratory of Precision Measurement Technology and Instrument, Department of Precision Instrument, Tsinghua University , Beijing, China
| | - Guanya Shi
- Department of Automotive Engineering, Tsinghua University , Beijing, China
| | - Peng Liu
- Department of Biomedical Engineering, Tsinghua University , Beijing, China
| | - Xiongying Ye
- State Key Laboratory of Precision Measurement Technology and Instrument, Department of Precision Instrument, Tsinghua University , Beijing, China
| | - Wenhui Wang
- State Key Laboratory of Precision Measurement Technology and Instrument, Department of Precision Instrument, Tsinghua University , Beijing, China
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Arrabito G, Cavaleri F, Montalbano V, Vetri V, Leone M, Pignataro B. Monitoring few molecular binding events in scalable confined aqueous compartments by raster image correlation spectroscopy (CADRICS). LAB ON A CHIP 2016; 16:4666-4676. [PMID: 27812580 DOI: 10.1039/c6lc01072e] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The assembly of scalable liquid compartments for binding assays in array formats constitutes a topic of fundamental importance in life sciences. This challenge can be addressed by mimicking the structure of cellular compartments with biological native conditions. Here, inkjet printing is employed to develop up to hundreds of picoliter aqueous droplet arrays stabilized by oil-confinement with mild surfactants (Tween-20). The aqueous environments constitute specialized compartments in which biomolecules may exploit their function and a wide range of molecular interactions can be quantitatively investigated. Raster Image Correlation Spectroscopy (RICS) is employed to monitor in each compartment a restricted range of dynamic intermolecular events demonstrated through protein-binding assays involving the biotin/streptavidin model system.
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Affiliation(s)
- G Arrabito
- Dipartimento di Fisica e Chimica, Università degli Studi di Palermo, Ed. 17, V.le delle Scienze, 90128 Palermo, Italy.
| | - F Cavaleri
- Dipartimento di Fisica e Chimica, Università degli Studi di Palermo, Ed. 17, V.le delle Scienze, 90128 Palermo, Italy.
| | - V Montalbano
- Dipartimento di Fisica e Chimica, Università degli Studi di Palermo, Ed. 17, V.le delle Scienze, 90128 Palermo, Italy.
| | - V Vetri
- Dipartimento di Fisica e Chimica, Università degli Studi di Palermo, Ed. 17, V.le delle Scienze, 90128 Palermo, Italy. and Aten Center, Università degli Studi di Palermo, Ed. 18, V.le delle Scienze, 90128 Palermo, Italy
| | - M Leone
- Dipartimento di Fisica e Chimica, Università degli Studi di Palermo, Ed. 17, V.le delle Scienze, 90128 Palermo, Italy. and Aten Center, Università degli Studi di Palermo, Ed. 18, V.le delle Scienze, 90128 Palermo, Italy
| | - B Pignataro
- Dipartimento di Fisica e Chimica, Università degli Studi di Palermo, Ed. 17, V.le delle Scienze, 90128 Palermo, Italy. and Aten Center, Università degli Studi di Palermo, Ed. 18, V.le delle Scienze, 90128 Palermo, Italy
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Banterle N, Lemke EA. Nanoscale devices for linkerless long-term single-molecule observation. Curr Opin Biotechnol 2016; 39:105-112. [PMID: 26990172 PMCID: PMC7611743 DOI: 10.1016/j.copbio.2016.02.013] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2015] [Revised: 02/11/2016] [Accepted: 02/15/2016] [Indexed: 01/07/2023]
Abstract
Total internal reflection fluorescence microscopy (TIRFM) can offer favorably high signal-to-noise observation of biological mechanisms. TIRFM can be used routinely to observe even single fluorescent molecules for a long duration (several seconds) at millisecond time resolution. However, to keep the investigated sample in the evanescent field, chemical surface immobilization techniques typically need to be implemented. In this review, we describe some of the recently developed novel nanodevices that overcome this limitation enabling long-term observation of free single molecules and outline their biological applications. The working concept of many devices is compatible with high-throughput strategies, which will further help to establish unbiased single molecule observation as a routine tool in biology to study the molecular underpinnings of even the most complex biological mechanisms.
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Affiliation(s)
- Niccolò Banterle
- Structural and Computational Biology Unit and Cell Biology and Biophysics Unit, European Molecular Biology Laboratory (EMBL), Meyerhofstrasse 1, 69117 Heidelberg, Germany
| | - Edward A Lemke
- Structural and Computational Biology Unit and Cell Biology and Biophysics Unit, European Molecular Biology Laboratory (EMBL), Meyerhofstrasse 1, 69117 Heidelberg, Germany.
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