1
|
Messina TC, Srijanto BR, Collier CP, Kravchenko II, Richards CI. Gold Ion Beam Milled Gold Zero-Mode Waveguides. NANOMATERIALS (BASEL, SWITZERLAND) 2022; 12:1755. [PMID: 35630978 PMCID: PMC9147361 DOI: 10.3390/nano12101755] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Revised: 05/13/2022] [Accepted: 05/17/2022] [Indexed: 12/02/2022]
Abstract
Zero-mode waveguides (ZMWs) are widely used in single molecule fluorescence microscopy for their enhancement of emitted light and the ability to study samples at physiological concentrations. ZMWs are typically produced using photo or electron beam lithography. We report a new method of ZMW production using focused ion beam (FIB) milling with gold ions. We demonstrate that ion-milled gold ZMWs with 200 nm apertures exhibit similar plasmon-enhanced fluorescence seen with ZMWs fabricated with traditional techniques such as electron beam lithography.
Collapse
Affiliation(s)
- Troy C. Messina
- Department of Physics, Berea College, 101 Chestnut Street, Berea, KY 40404, USA
| | - Bernadeta R. Srijanto
- Center for Nanophase Materials Science, Oak Ridge National Labs, Oak Ridge, TN 37831, USA; (B.R.S.); (C.P.C.); (I.I.K.)
| | - Charles Patrick Collier
- Center for Nanophase Materials Science, Oak Ridge National Labs, Oak Ridge, TN 37831, USA; (B.R.S.); (C.P.C.); (I.I.K.)
| | - Ivan I. Kravchenko
- Center for Nanophase Materials Science, Oak Ridge National Labs, Oak Ridge, TN 37831, USA; (B.R.S.); (C.P.C.); (I.I.K.)
| | - Christopher I. Richards
- Department of Chemistry, University of Kentucky, 209 Chemistry-Physics Building, Lexington, KY 40202, USA;
| |
Collapse
|
2
|
Bene L, Bagdány M, Ungvári T, Damjanovich L. Information theoretic FRET calibration on the cell surface. J Photochem Photobiol A Chem 2021. [DOI: 10.1016/j.jphotochem.2021.113144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
|
3
|
Tavakoli M, Taylor JN, Li CB, Komatsuzaki T, Pressé S. Single Molecule Data Analysis: An Introduction. ADVANCES IN CHEMICAL PHYSICS 2017. [DOI: 10.1002/9781119324560.ch4] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Meysam Tavakoli
- Physics Department; Indiana University-Purdue University Indianapolis; Indianapolis IN 46202 USA
| | - J. Nicholas Taylor
- Research Institute for Electronic Science; Hokkaido University; Kita 20 Nishi 10 Kita-Ku Sapporo 001-0020 Japan
| | - Chun-Biu Li
- Research Institute for Electronic Science; Hokkaido University; Kita 20 Nishi 10 Kita-Ku Sapporo 001-0020 Japan
- Department of Mathematics; Stockholm University; 106 91 Stockholm Sweden
| | - Tamiki Komatsuzaki
- Research Institute for Electronic Science; Hokkaido University; Kita 20 Nishi 10 Kita-Ku Sapporo 001-0020 Japan
| | - Steve Pressé
- Physics Department; Indiana University-Purdue University Indianapolis; Indianapolis IN 46202 USA
- Department of Chemistry and Chemical Biology; Indiana University-Purdue University Indianapolis; Indianapolis IN 46202 USA
- Department of Cell and Integrative Physiology; Indiana University School of Medicine; Indianapolis IN 46202 USA
- Department of Physics and School of Molecular Sciences; Arizona State University; Tempe AZ 85287 USA
| |
Collapse
|
4
|
Ochoa MA, Zhou X, Chen P, Loring RF. Interpreting single turnover catalysis measurements with constrained mean dwell times. J Chem Phys 2012; 135:174509. [PMID: 22070308 DOI: 10.1063/1.3657855] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Observation of a chemical transformation at the single-molecule level yields a detailed view of kinetic pathways contributing to the averaged results obtained in a bulk measurement. Studies of a fluorogenic reaction catalyzed by gold nanoparticles have revealed heterogeneous reaction dynamics for these catalysts. Measurements on single nanoparticles yield binary trajectories with stochastic transitions between a dark state in which no product molecules are adsorbed and a fluorescent state in which one product molecule is present. The mean dwell time in either state gives information corresponding to a bulk measurement. Quantifying fluctuations from mean kinetics requires identifying properties of the fluorescence trajectory that are selective in emphasizing certain dynamic processes according to their time scales. We propose the use of constrained mean dwell times, defined as the mean dwell time in a state with the constraint that the immediately preceding dwell time in the other state is, for example, less than a variable time. Calculations of constrained mean dwell times for a kinetic model with dynamic disorder demonstrate that these quantities reveal correlations among dynamic fluctuations at different active sites on a multisite catalyst. Constrained mean dwell times are determined from measurements of single nanoparticle catalysis. The results indicate that dynamical fluctuations at different active sites are correlated, and that especially rapid reaction events produce particularly slowly desorbing product molecules.
Collapse
Affiliation(s)
- Maicol A Ochoa
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853, USA
| | | | | | | |
Collapse
|
5
|
Backović M, Price ES, Johnson CK, Ralston JP. A distribution-based method to resolve single-molecule Förster resonance energy transfer observations. J Chem Phys 2011; 134:145101. [PMID: 21495770 DOI: 10.1063/1.3568946] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We introduce a new approach to analyze single-molecule Förster resonance energy transfer (FRET) data. The method recognizes that FRET efficiencies assumed by traditional ensemble methods are unobservable for single molecules. We propose instead a method to predict distributions of FRET parameters obtained directly from the data. Distributions of FRET rates, given the data, are precisely defined using Bayesian methods and increase the information derived from the data. Benchmark comparisons find that the response time of the new method outperforms traditional methods of averaging. Our approach makes no assumption about the number or distribution of underlying FRET states. The new method also yields information about joint parameter distributions going beyond the standard framework of FRET analysis. For example, the running distribution of FRET means contains more information than any conceivable single measure of FRET efficiency. The method is tested against simulated data and then applied to a pilot-study sample of calmodulin molecules immobilized in lipid vesicles, revealing evidence for multiple dynamical states.
Collapse
Affiliation(s)
- Mihailo Backović
- Department of Physics & Astronomy. University of Kansas, Lawrence, Kansas 66045, USA.
| | | | | | | |
Collapse
|
6
|
Boghossian AA, Zhang J, Le Floch-Yin FT, Ulissi ZW, Bojo P, Han JH, Kim JH, Arkalgud JR, Reuel NF, Braatz RD, Strano MS. The chemical dynamics of nanosensors capable of single-molecule detection. J Chem Phys 2011; 135:084124. [DOI: 10.1063/1.3606496] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
7
|
Boghossian AA, Zhang J, Barone PW, Reuel NF, Kim JH, Heller DA, Ahn JH, Hilmer AJ, Rwei A, Arkalgud JR, Zhang CT, Strano MS. Near-infrared fluorescent sensors based on single-walled carbon nanotubes for life sciences applications. CHEMSUSCHEM 2011; 4:848-63. [PMID: 21751417 DOI: 10.1002/cssc.201100070] [Citation(s) in RCA: 102] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Many properties of single-walled carbon nanotubes (SWCNTs) make them ideal candidates for sensors, particularly for biological systems. Both their fluorescence in the near-infrared range of 820-1600 nm, where absorption by biological tissues is often minimal, and their inherent photostability are desirable attributes for the design of in vitro and in vivo sensors. The mechanisms by which a target molecule can selectively alter the fluorescent emission include primarily changes in emission wavelength (i.e., solvatochromism) and intensity, including effects such as charge-transfer transition bleaching and exciton quenching. The central challenge lies in engineering the nanotube interface to be selective for the analyte of interest. In this work, we review the recent development in this area over the past few years, and describe the design rules that we have developed for detecting various analytes, ranging from stable small molecules and reactive oxygen species (ROS) or reactive nitrogen species (RNS) to macromolecules. Applications to in vivo sensor measurements using these sensors are also described. In addition, the emerging field of SWCNT-based single-molecule detection using band gap fluorescence and the recent efforts to accurately quantify and utilize this unique class of stochastic sensors are also described in this article.
Collapse
Affiliation(s)
- Ardemis A Boghossian
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
8
|
Liu Y, Park J, Dahmen KA, Chemla YR, Ha T. A comparative study of multivariate and univariate hidden Markov modelings in time-binned single-molecule FRET data analysis. J Phys Chem B 2010; 114:5386-403. [PMID: 20361785 DOI: 10.1021/jp9057669] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We compare two different types of hidden Markov modeling (HMM) algorithms, e.g., multivariate HMM (MHMM) and univariate HMM (UHMM), for the analysis of time-binned single-molecule fluorescence energy transfer (smFRET) data. In MHMM, the original two channel signals, i.e., the donor fluorescence intensity (I(D)) and acceptor fluorescence intensity (I(A)), are simultaneously analyzed. However, in UHMM, only the calculated FRET trajectory is analyzed. On the basis of the analysis of both synthetic and experimental data, we find that, if the noise in the signal is described with a proper probability distribution, MHMM generally outperforms UHMM. We also show that, in the case of multiple trajectories, analyzing them simultaneously gives better results than averaging over individual analysis results.
Collapse
Affiliation(s)
- Yang Liu
- Center for the Physics of Living Cell, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
| | | | | | | | | |
Collapse
|
9
|
Jäger M, Kiel A, Herten DP, Hamprecht FA. Analysis of single-molecule fluorescence spectroscopic data with a Markov-modulated Poisson process. Chemphyschem 2009; 10:2486-95. [PMID: 19644999 DOI: 10.1002/cphc.200900331] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
We present a photon-by-photon analysis framework for the evaluation of data from single-molecule fluorescence spectroscopy (SMFS) experiments using a Markov-modulated Poisson process (MMPP). A MMPP combines a discrete (and hidden) Markov process with an additional Poisson process reflecting the observation of individual photons. The algorithmic framework is used to automatically analyze the dynamics of the complex formation and dissociation of Cu2+ ions with the bidentate ligand 2,2'-bipyridine-4,4'dicarboxylic acid in aqueous media. The process of association and dissociation of Cu2+ ions is monitored with SMFS. The dcbpy-DNA conjugate can exist in two or more distinct states which influence the photon emission rates. The advantage of a photon-by-photon analysis is that no information is lost in preprocessing steps. Different model complexities are investigated in order to best describe the recorded data and to determine transition rates on a photon-by-photon basis. The main strength of the method is that it allows to detect intermittent phenomena which are masked by binning and that are difficult to find using correlation techniques when they are short-lived.
Collapse
Affiliation(s)
- Mark Jäger
- Philips Research, High Tech Campus 34, 5656AE Eindhoven, The Netherlands
| | | | | | | |
Collapse
|
10
|
Talaga DS. Information-theoretical analysis of time-correlated single-photon counting measurements of single molecules. J Phys Chem A 2009; 113:5251-63. [PMID: 19385684 PMCID: PMC2767183 DOI: 10.1021/jp8082908] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Time-correlated single photon counting allows luminescence lifetime information to be determined on a single molecule level. This paper develops a formalism to allow information theory analysis of the ability of luminescence lifetime measurements to resolve states in a single molecule. It analyzes the information content of the photon stream and the fraction of that information that is relevant to the state determination problem. Experimental losses of information due to instrument response, digitization, and different types of background are calculated and a procedure to determine the optimal value of experimental parameters is demonstrated. This paper shows how to use the information theoretical formalism to evaluate the number of photons required to distinguish dyes that differ only by lifetime. It extends this idea to include distinguishing molecular states that differ in the electron transfer quenching or resonant energy transfer and shows how the differences between the lifetime of signal and background can help distinguish the dye position in an excitation beam.
Collapse
Affiliation(s)
- David S Talaga
- Rutgers, the State University of New Jersey, New Brunswick, New Jersey 08854, USA.
| |
Collapse
|
11
|
Petrášek Z, Schwille P. Fluctuations as a source of information in fluorescence microscopy. J R Soc Interface 2008. [DOI: 10.1098/rsif.2008.0200.focus] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Fluctuations in fluorescence spectroscopy and microscopy have traditionally been regarded as noise—they lower the resolution and contrast and do not permit high acquisition rates. However, fluctuations can also be used to gain additional information about a system. This fact has been exploited in single-point microscopic techniques, such as fluorescence correlation spectroscopy and analysis of single molecule trajectories, and also in the imaging field, e.g. in spatio-temporal image correlation spectroscopy. Here, we discuss how fluctuations are used to obtain more quantitative information from the data than that given by average values, while minimizing the effects of noise due to stochastic photon detection.
Collapse
Affiliation(s)
- Zdeněk Petrášek
- Biophysics group, Biotechnologisches Zentrum, Technische Universität DresdenTatzberg 47-51, 01307 Dresden, Germany
| | - Petra Schwille
- Biophysics group, Biotechnologisches Zentrum, Technische Universität DresdenTatzberg 47-51, 01307 Dresden, Germany
| |
Collapse
|
12
|
Deniz AA, Mukhopadhyay S, Lemke EA. Single-molecule biophysics: at the interface of biology, physics and chemistry. J R Soc Interface 2008; 5:15-45. [PMID: 17519204 PMCID: PMC2094721 DOI: 10.1098/rsif.2007.1021] [Citation(s) in RCA: 174] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Single-molecule methods have matured into powerful and popular tools to probe the complex behaviour of biological molecules, due to their unique abilities to probe molecular structure, dynamics and function, unhindered by the averaging inherent in ensemble experiments. This review presents an overview of the burgeoning field of single-molecule biophysics, discussing key highlights and selected examples from its genesis to our projections for its future. Following brief introductions to a few popular single-molecule fluorescence and manipulation methods, we discuss novel insights gained from single-molecule studies in key biological areas ranging from biological folding to experiments performed in vivo.
Collapse
Affiliation(s)
- Ashok A Deniz
- Department of Molecular Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA.
| | | | | |
Collapse
|
13
|
Abstract
This article examines the current status of Markov processes in single molecule fluorescence. For molecular dynamics to be described by a Markov process, the Markov process must include all states involved in the dynamics and the FPT distributions out of those states must be describable by a simple exponential law. The observation of non-exponential first-passage time distributions or other evidence of non-Markovian dynamics is common in single molecule studies and offers an opportunity to expand the Markov model to include new dynamics or states that improve understanding of the system.
Collapse
Affiliation(s)
- David S Talaga
- Rutgers, The State University of New Jersey, Department of Chemistry and Chemical Biology, 610 Taylor Road, Piscataway, NJ 08854
| |
Collapse
|
14
|
Messina TC, Kim H, Giurleo JT, Talaga DS. Hidden Markov model analysis of multichromophore photobleaching. J Phys Chem B 2007; 110:16366-76. [PMID: 16913765 PMCID: PMC1995553 DOI: 10.1021/jp063367k] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The interpretation of single-molecule measurements is greatly complicated by the presence of multiple fluorescent labels. However, many molecular systems of interest consist of multiple interacting components. We investigate this issue using multiply labeled dextran polymers that we intentionally photobleach to the background on a single-molecule basis. Hidden Markov models allow for unsupervised analysis of the data to determine the number of fluorescent subunits involved in the fluorescence intermittency of the 6-carboxy-tetramethylrhodamine labels by counting the discrete steps in fluorescence intensity. The Bayes information criterion allows us to distinguish between hidden Markov models that differ by the number of states, that is, the number of fluorescent molecules. We determine information-theoretical limits and show via Monte Carlo simulations that the hidden Markov model analysis approaches these theoretical limits. This technique has resolving power of one fluorescing unit up to as many as 30 fluorescent dyes with the appropriate choice of dye and adequate detection capability. We discuss the general utility of this method for determining aggregation-state distributions as could appear in many biologically important systems and its adaptability to general photometric experiments.
Collapse
Affiliation(s)
| | | | | | - David S. Talaga
- * To whom correspondence should be addressed. E-mail: . URL: http://talaga.rutgers.edu
| |
Collapse
|
15
|
Burrows SM, Reif RD, Pappas D. Investigation of photobleaching and saturation of single molecules by fluorophore recrossing events. Anal Chim Acta 2007; 598:135-42. [PMID: 17693317 DOI: 10.1016/j.aca.2007.07.026] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2007] [Revised: 07/10/2007] [Accepted: 07/11/2007] [Indexed: 11/17/2022]
Abstract
A method for investigation of photobleaching and saturation of single molecules by fluorophore recrossing events in a laser beam is described. The diffraction-limited probe volumes encountered in single-molecule detection (SMD) produce high excitation irradiance, which can decrease available signal. The single molecules of several dyes were detected and the data was used to extract interpeak times above a defined threshold value. The interpeak times revealed the number of fluorophore recrossing events. The number of molecules detected that were within 2 ms of each other represented a molecular recrossing for this work. Calcein, fluorescein and R-phycoerythrin were analyzed and the saturation irradiance and photobleaching effects were determined as a function of irradiance. This approach is simple and it serves as a method of optimizing experimental conditions for single-molecule detection.
Collapse
Affiliation(s)
- Sean M Burrows
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX 79409-1061, United States
| | | | | |
Collapse
|
16
|
Laurence TA, Kwon Y, Yin E, Hollars CW, Camarero JA, Barsky D. Correlation spectroscopy of minor fluorescent species: signal purification and distribution analysis. Biophys J 2006; 92:2184-98. [PMID: 17189306 PMCID: PMC1861789 DOI: 10.1529/biophysj.106.093591] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
We are performing experiments that use fluorescence resonance energy transfer (FRET) and fluorescence correlation spectroscopy (FCS) to monitor the movement of an individual donor-labeled sliding clamp protein molecule along acceptor-labeled DNA. In addition to the FRET signal sought from the sliding clamp-DNA complexes, the detection channel for FRET contains undesirable signal from free sliding clamp and free DNA. When multiple fluorescent species contribute to a correlation signal, it is difficult or impossible to distinguish between contributions from individual species. As a remedy, we introduce "purified FCS", which uses single molecule burst analysis to select a species of interest and extract the correlation signal for further analysis. We show that by expanding the correlation region around a burst, the correlated signal is retained and the functional forms of FCS fitting equations remain valid. We demonstrate the use of purified FCS in experiments with DNA sliding clamps. We also introduce "single-molecule FCS", which obtains diffusion time estimates for each burst using expanded correlation regions. By monitoring the detachment of weakly-bound 30-mer DNA oligomers from a single-stranded DNA plasmid, we show that single-molecule FCS can distinguish between bursts from species that differ by a factor of 5 in diffusion constant.
Collapse
Affiliation(s)
- Ted A Laurence
- Chemistry, Materials, and Life Sciences, Lawrence Livermore National Laboratory, Livermore, California, USA.
| | | | | | | | | | | |
Collapse
|