1
|
Mei X, Fang Q, Selvaganapathy PR. Three-dimensional oxygen concentration monitoring in hydrogels using low-cost phosphorescence lifetime imaging for tissue engineering. BIOMEDICAL OPTICS EXPRESS 2023; 14:4759-4774. [PMID: 37791279 PMCID: PMC10545174 DOI: 10.1364/boe.493340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 07/19/2023] [Accepted: 07/21/2023] [Indexed: 10/05/2023]
Abstract
Oxygen concentration measurement in 3D hydrogels is vital in 3D cell culture and tissue engineering. However, standard 3D imaging systems capable of measuring oxygen concentration with adequate precision are based on advanced microscopy platforms, which are not accessible in many laboratories due to the system's complexity and the high price. In this work, we present a fast and low-cost phosphorescence lifetime imaging design for measuring the lifetime of oxygen-quenched phosphorescence emission with 0.25 µs temporal precision and sub-millimeter spatial resolution in 3D. By combining light-sheet illumination and the frequency-domain lifetime measurement using a commercial rolling-shutter CMOS camera in the structure of a conventional optical microscope, this design is highly customizable to accommodate application-specific research needs while also being low-cost as compared to advanced instruments. As a demonstration, we made a fluidic device with a gas-permeable film to create an artificial oxygen gradient in the hydrogel sample. Dye-embedded beads were distributed in the hydrogel to conduct continuous emission lifetime monitoring when nitrogen was pumped through the fluidic channel and changed oxygen distribution in the sample. The dynamics of the changes in lifetime co-related with their location in the gel of size 0.5 mm×1.5 mm×700 µm demonstrate the ability of this design to measure the oxygen concentration stably and precisely in 3D samples.
Collapse
Affiliation(s)
- Xu Mei
- School of Biomedical Engineering, McMaster University, 1280 Main Street W, Hamilton, ON L8S 4L8, Canada
| | - Qiyin Fang
- School of Biomedical Engineering, McMaster University, 1280 Main Street W, Hamilton, ON L8S 4L8, Canada
- Department of Engineering Physics, McMaster University, 1280 Main Street W, Hamilton, ON L8S 4L8, Canada
| | - P. Ravi Selvaganapathy
- School of Biomedical Engineering, McMaster University, 1280 Main Street W, Hamilton, ON L8S 4L8, Canada
- Department of Mechanical Engineering, McMaster University, 1280 Main Street W, Hamilton, ON L8S 4L8, Canada
| |
Collapse
|
2
|
Bowman AJ, Kasevich MA. Resonant Electro-Optic Imaging for Microscopy at Nanosecond Resolution. ACS NANO 2021; 15:16043-16054. [PMID: 34546704 DOI: 10.1021/acsnano.1c04470] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
We demonstrate an electro-optic wide-field method to enable fluorescence lifetime microscopy (FLIM) with high throughput and single-molecule sensitivity. Resonantly driven Pockels cells are used to efficiently gate images at 39 MHz, allowing fluorescence lifetime to be captured on standard camera sensors. Lifetime imaging of single molecules is enabled in wide field with exposure times of less than 100 ms. This capability allows combination of wide-field FLIM with single-molecule super-resolution localization microscopy. Fast single-molecule dynamics such as FRET and molecular binding events are captured from wide-field images without prior spatial knowledge. A lifetime sensitivity of 1.9 times the photon shot-noise limit is achieved, and high throughput is shown by acquiring wide-field FLIM images with millisecond exposure and >108 photons per frame. Resonant electro-optic FLIM allows lifetime contrast in any wide-field microscopy method.
Collapse
Affiliation(s)
- Adam J Bowman
- Physics Department, Stanford University, 382 Via Pueblo Mall, Stanford, California 94305, United States
| | - Mark A Kasevich
- Physics Department, Stanford University, 382 Via Pueblo Mall, Stanford, California 94305, United States
| |
Collapse
|
3
|
Raspe M, Kedziora KM, van den Broek B, Zhao Q, de Jong S, Herz J, Mastop M, Goedhart J, Gadella TWJ, Young IT, Jalink K. siFLIM: single-image frequency-domain FLIM provides fast and photon-efficient lifetime data. Nat Methods 2016; 13:501-4. [DOI: 10.1038/nmeth.3836] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2015] [Accepted: 03/11/2016] [Indexed: 11/09/2022]
|
4
|
|
5
|
Turgeman L, Fixler D. The influence of dead time related distortions on live cell fluorescence lifetime imaging (FLIM) experiments. JOURNAL OF BIOPHOTONICS 2014; 7:442-452. [PMID: 23674214 DOI: 10.1002/jbio.201300018] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2013] [Revised: 03/10/2013] [Accepted: 04/23/2013] [Indexed: 06/02/2023]
Abstract
Recent developments in the field of fluorescence lifetime imaging microscopy (FLIM) techniques allow the use of high repetition rate light sources in live cell experiments. For light sources with a repetition rate of 20-100 MHz, the time-correlated single photon counting (TCSPC) FLIM systems suffer serious dead time related distortions, known as "inter-pulse pile-up". The objective of this paper is to present a new method to quantify the level of signal distortion in TCSPC FLIM experiments, in order to determine the most efficient laser repetition rate for different FLT ranges. Optimization of the F -value, which is the relation between the relative standard deviation (RSD) in the measured FLT to the RSD in the measured fluorescence intensity (FI), allows quantification of the level of FI signal distortion, as well as determination of the correct FLT of the measurement. It is shown that by using a very high repetition rate (80 MHz) for samples characterized by high real FLT's (4-5 ns), virtual short FLT components are added to the FLT histogram while a F -value that is higher than 1 is obtained. For samples characterized with short real FLT's, virtual long FLT components are added to the FLT histogram with the lower repetition rate (20-50 MHz), while by using a higher repetition rate (80 MHz) the "inter-pulse pile-up" is eliminated as the F -value is close to 1.
Collapse
Affiliation(s)
- Lior Turgeman
- Faculty of Engineering and Institute of Nanotechnology and Advanced Materials, Bar Ilan University, Ramat Gan, 52900, Israel
| | | |
Collapse
|
6
|
Jin D, Lu Y, Leif RC, Yang S, Rajendran M, Miller LW. How to build a time-gated luminescence microscope. ACTA ACUST UNITED AC 2014; 67:2.22.1-2.22.36. [PMID: 24510771 DOI: 10.1002/0471142956.cy0222s67] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The sensitivity of filter-based fluorescence microscopy techniques is limited by autofluorescence background. Time-gated detection is a practical way to suppress autofluorescence, enabling higher contrast and improved sensitivity. In the past few years, three groups of authors have demonstrated independent approaches to build robust versions of time-gated luminescence microscopes. Three detailed, step-by-step protocols are provided here for modifying standard fluorescent microscopes to permit imaging time-gated luminescence.
Collapse
Affiliation(s)
- Dayong Jin
- Advanced Cytometry Laboratories, MQ BioFocus Research Centre & Photonics Research Centre, Macquarie University, New South Wales, Australia
| | - Yiqing Lu
- Advanced Cytometry Laboratories, MQ BioFocus Research Centre & Photonics Research Centre, Macquarie University, New South Wales, Australia
| | | | - Sean Yang
- Newport Instruments, San Diego, California
| | - Megha Rajendran
- Department of Chemistry, University of Illinois at Chicago, Chicago, Illinois
| | - Lawrence W Miller
- Department of Chemistry, University of Illinois at Chicago, Chicago, Illinois
| |
Collapse
|
7
|
Wang D, Moyer A, Henderson M. Intensity fluctuation spectra of dynamic laser speckle patterns acquired by a full-field temporal modulation method. APPLIED OPTICS 2012; 51:7576-7580. [PMID: 23128705 DOI: 10.1364/ao.51.007576] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2012] [Accepted: 09/30/2012] [Indexed: 06/01/2023]
Abstract
A method for obtaining the intensity fluctuation spectra of dynamic laser speckle patterns is introduced, which is based on the temporal modulation of the illumination and the subsequent integration of the intensity signals. This approach does not rely on the fast sampling rate to meet the Nyquist criterion, making it applicable for full-field imaging applications. The intensity fluctuation spectra created by the in-plane motion of a random phase object was investigated by using both a single-channel detector and a multichannel sensor. The power spectra obtained by using the full-field temporal modulation method were found to agree with the homodyne Doppler spectra obtained by using the method of autocorrelation and Fourier transform.
Collapse
Affiliation(s)
- Dake Wang
- Department of Physics, Furman University, Greenville, South Carolina 29613, USA.
| | | | | |
Collapse
|
8
|
|
9
|
|
10
|
Li DDU, Arlt J, Tyndall D, Walker R, Richardson J, Stoppa D, Charbon E, Henderson RK. Video-rate fluorescence lifetime imaging camera with CMOS single-photon avalanche diode arrays and high-speed imaging algorithm. JOURNAL OF BIOMEDICAL OPTICS 2011; 16:096012. [PMID: 21950926 DOI: 10.1117/1.3625288] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
A high-speed and hardware-only algorithm using a center of mass method has been proposed for single-detector fluorescence lifetime sensing applications. This algorithm is now implemented on a field programmable gate array to provide fast lifetime estimates from a 32 × 32 low dark count 0.13 μm complementary metal-oxide-semiconductor single-photon avalanche diode (SPAD) plus time-to-digital converter array. A simple look-up table is included to enhance the lifetime resolvability range and photon economics, making it comparable to the commonly used least-square method and maximum-likelihood estimation based software. To demonstrate its performance, a widefield microscope was adapted to accommodate the SPAD array and image different test samples. Fluorescence lifetime imaging microscopy on fluorescent beads in Rhodamine 6G at a frame rate of 50 fps is also shown.
Collapse
Affiliation(s)
- David D-U Li
- University of Sussex, Biomedical Engineering Group, Department of Engineering and Design, School of Engineering and Informatics, Brighton BN1 9QT, United Kingdom.
| | | | | | | | | | | | | | | |
Collapse
|
11
|
Zhao Q, Young IT, de Jong JGS. Photon budget analysis for fluorescence lifetime imaging microscopy. JOURNAL OF BIOMEDICAL OPTICS 2011; 16:086007. [PMID: 21895319 DOI: 10.1117/1.3608997] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We have constructed a mathematical model to analyze the photon efficiency of frequency-domain fluorescence lifetime imaging microscopy (FLIM). The power of the light source needed for illumination in a FLIM system and the signal-to-noise ratio of the detector have led us to a photon "budget." These measures are relevant to many fluorescence microscope users and the results are not restricted to FLIM but applicable to widefield fluorescence microscopy in general. Limitations in photon numbers, however, are more of an issue with FLIM compared to other less quantitative types of imaging. By modeling a typical experimental configuration, examples are given for fluorophores whose absorption peaks span the visible spectrum from Fura-2 to Cy5. We have performed experiments to validate the assumptions and parameters used in our mathematical model. The influence of fluorophore concentration on the intensity of the fluorescence emission light and the Poisson distribution assumption of the detected fluorescence emission light have been validated. The experimental results agree well with the mathematical model. This photon budget is important in order to characterize the constraints involved in current fluorescent microscope systems that are used for lifetime as well as intensity measurements and to design and fabricate new systems.
Collapse
Affiliation(s)
- Qiaole Zhao
- Delft University of Technology, Department of Imaging Science and Technology, The Netherlands
| | | | | |
Collapse
|
12
|
Petrášek Z, Suhling K. Photon arrival timing with sub-camera exposure time resolution in wide-field time-resolved photon counting imaging. OPTICS EXPRESS 2010; 18:24888-901. [PMID: 21164834 DOI: 10.1364/oe.18.024888] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
We demonstrate that an ultra-fast CMOS camera combined with a photon counting image intensifier can be used to determine photon arrival times well below the exposure time of the camera. We can obtain a time resolution down to around 1% of the exposure time, i.e. of the order of 40 ns with microsecond exposure times. This is achieved by exploiting the invariant phosphor decay of the image intensifier's phosphor screen: Developing a suitable mathematical framework, we show that the relative intensities of the phosphor decay in successive frames following the photon detection uniquely determine the photon arrival time. This approach opens a way to measuring fast luminescence decays in parallel in many pixels. Possible applications include oxygen and ion concentration imaging using probes with luminescence lifetimes in the range of 100 ns to microseconds.
Collapse
Affiliation(s)
- Zdeněk Petrášek
- Biotechnologisches Zentrum, Technische Universität Dresden, Tatzberg 47/49, 01307 Dresden, Germany.
| | | |
Collapse
|
13
|
Suhling K, Sergent N, Levitt J, Green M. Rapid wide-field photon counting imaging with microsecond time resolution. OPTICS EXPRESS 2010; 18:25292-25298. [PMID: 21164877 DOI: 10.1364/oe.18.025292] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We report a novel wide-field imaging method capable of time-correlated single photon counting. It is based on a photon counting image intensifier coupled to an ultra-fast CMOS camera running at 40 kHz frame rate. Using a pulsed excitation source and decaying luminescent sample, the arrival times of hundreds of photons can be determined simultaneously in many pixels with microsecond resolution and reduced photon pile-up. The detection system is mounted on an inverted microscope and applied to time-resolved imaging of Europium-containing polyoxometalate nanoparticles.
Collapse
Affiliation(s)
- Klaus Suhling
- Department of Physics, King’s College London, Strand, London WC2R 2LS, UK
| | | | | | | |
Collapse
|
14
|
Huang TCD, Sorgenfrei S, Gong P, Levicky R, Shepard KL. A 0.18-µm CMOS Array Sensor for Integrated Time-Resolved Fluorescence Detection. IEEE JOURNAL OF SOLID-STATE CIRCUITS 2009; 44:1644-1654. [PMID: 20436922 PMCID: PMC2860634 DOI: 10.1109/jssc.2009.2016994] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
This paper describes the design of an active, integrated CMOS sensor array for fluorescence applications which enables time-gated, time-resolved fluorescence spectroscopy. The 64-by-64 array is sensitive to photon densities as low as 8.8 × 10(6) photons/cm(2) with 64-point averaging and, through a differential pixel design, has a measured impulse response of better than 800 ps. Applications include both active microarrays and high-frame-rate imagers for fluorescence lifetime imaging microscopy.
Collapse
Affiliation(s)
- Ta-chien D. Huang
- Columbia Bioelectronics Systems Laboratory, Department of Electrical Engineering, Columbia University, New York, NY 10027 USA
| | - Sebastian Sorgenfrei
- Columbia Bioelectronics Systems Laboratory, Department of Electrical Engineering, Columbia University, New York, NY 10027 USA
| | - Ping Gong
- Columbia Bioelectronics Systems Laboratory, Department of Electrical Engineering, Columbia University, New York, NY 10027 USA
| | - Rastislav Levicky
- Department of Chemical and Biological Engineering. Polytechnic University, Brooklyn, NY 11201 USA
| | - Kenneth L. Shepard
- Columbia Bioelectronics Systems Laboratory, Department of Electrical Engineering, Columbia University, New York, NY 10027 USA
| |
Collapse
|
15
|
Wong WP, Halvorsen K. Beyond the frame rate: measuring high-frequency fluctuations with light-intensity modulation. OPTICS LETTERS 2009; 34:277-9. [PMID: 19183630 DOI: 10.1364/ol.34.000277] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Power-spectral-density measurements of any sampled signal are typically restricted by both acquisition rate and frequency response limitations of instruments, which can be particularly prohibitive for video-based measurements. We have developed a new method called intensity modulation spectral analysis that circumvents these limitations, dramatically extending the effective detection bandwidth. We demonstrate this by video tracking an optically trapped microsphere while oscillating an LED illumination source. This approach allows us to quantify fluctuations of the microsphere at frequencies over 10 times higher than the Nyquist frequency, mimicking a significantly higher frame rate.
Collapse
Affiliation(s)
- Wesley P Wong
- The Rowland Institute at Harvard, Harvard University, Cambridge, MA 02142, USA.
| | | |
Collapse
|
16
|
Verveer PJ, Hanley QS. Chapter 2 Frequency domain FLIM theory, instrumentation, and data analysis. FRET AND FLIM TECHNIQUES 2009. [DOI: 10.1016/s0075-7535(08)00002-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
|
17
|
Hille C, Berg M, Bressel L, Munzke D, Primus P, Löhmannsröben HG, Dosche C. Time-domain fluorescence lifetime imaging for intracellular pH sensing in living tissues. Anal Bioanal Chem 2008; 391:1871-9. [DOI: 10.1007/s00216-008-2147-0] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2008] [Accepted: 04/16/2008] [Indexed: 10/22/2022]
|
18
|
Elder AD, Frank JH, Swartling J, Dai X, Kaminski CF. Calibration of a wide-field frequency-domain fluorescence lifetime microscopy system using light emitting diodes as light sources. J Microsc 2006; 224:166-80. [PMID: 17204064 DOI: 10.1111/j.1365-2818.2006.01689.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
High brightness light emitting diodes are an inexpensive and versatile light source for wide-field frequency-domain fluorescence lifetime imaging microscopy. In this paper a full calibration of an LED based fluorescence lifetime imaging microscopy system is presented for the first time. A radio-frequency generator was used for simultaneous modulation of light emitting diode (LED) intensity and the gain of an intensified charge coupled device (CCD) camera. A homodyne detection scheme was employed to measure the demodulation and phase shift of the emitted fluorescence, from which phase and modulation lifetimes were determined at each image pixel. The system was characterized both in terms of its sensitivity to measure short lifetimes (500 ps to 4 ns), and its capability to distinguish image features with small lifetime differences. Calibration measurements were performed in quenched solutions containing Rhodamine 6G dye and the results compared to several independent measurements performed with other measurement methodologies, including time correlated single photon counting, time gated detection, and acousto optical modulator (AOM) based modulation of excitation sources. Results are presented from measurements and simulations. The effects of limited signal-to-noise ratios, baseline drifts and calibration errors are discussed in detail. The implications of limited modulation bandwidth of high brightness, large area LED devices ( approximately 40 MHz for devices used here) are presented. The results show that phase lifetime measurements are robust down to sub ns levels, whereas modulation lifetimes are prone to errors even at large signal-to-noise ratios. Strategies for optimizing measurement fidelity are discussed. Application of the fluorescence lifetime imaging microscopy system is illustrated with examples from studies of molecular mixing in microfluidic devices and targeted drug delivery research.
Collapse
Affiliation(s)
- A D Elder
- Department of Chemical Engineering, University of Cambridge, Pembroke Street, Cambridge, UK
| | | | | | | | | |
Collapse
|
19
|
Elder AD, Matthews SM, Swartling J, Yunus K, Frank JH, Brennan CM, Fisher AC, Kaminski CF. Application of frequency-domain Fluorescence Lifetime Imaging Microscopy as a quantitative analytical tool for microfluidic devices. OPTICS EXPRESS 2006; 14:5456-5467. [PMID: 19516711 DOI: 10.1364/oe.14.005456] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
We describe the application of wide-field frequency domain Fluorescence Lifetime Imaging Microscopy (FLIM) to imaging in microfluidic devices. FLIM is performed using low cost, intensity modulated Light Emitting Diodes (LEDs) for illumination. The use of lifetime imaging for quantitative analysis within such devices is demonstrated by mapping the molecular diffusion of iodide ions across a microchannel.
Collapse
|
20
|
Esposito A, Gerritsen HC, Oggier T, Lustenberger F, Wouters FS. Innovating lifetime microscopy: a compact and simple tool for life sciences, screening, and diagnostics. JOURNAL OF BIOMEDICAL OPTICS 2006; 11:34016. [PMID: 16822066 DOI: 10.1117/1.2208999] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Fluorescence lifetime imaging microscopy (FLIM) allows the investigation of the physicochemical environment of fluorochromes and protein-protein interaction mapping by Forster resonance energy transfer (FRET) in living cells. However, simpler and cheaper solutions are required before this powerful analytical technique finds a broader application in the life sciences. Wide-field frequency-domain FLIM represents a solution whose application is currently limited by the need for multichannel-plate image intensifiers. We recently showed the feasibility of using a charge-coupled device/complementory metal-oxide semiconductor (CCD/CMOS) hybrid lock-in imager, originally developed for 3-D vision, as an add-on device for lifetime measurements on existing wide-field microscopes. In the present work, the performance of the setup is validated by comparison with well-established wide-field frequency-domain FLIM measurements. Furthermore, we combine the lock-in imager with solid-state light sources. This results in a simple, inexpensive, and compact FLIM system, operating at a video rate and capable of single-shot acquisition by virtue of the unique parallel retrieval of two phase-dependent images. This novel FLIM setup is used for cellular and FRET imaging, and for high-throughput and fast imaging applications. The all-solid-state design bridges the technological gap that limits the use of FLIM in areas such as drug discovery and medical diagnostics.
Collapse
|
21
|
Elson DS, Galletly N, Talbot C, Requejo-Isidro J, McGinty J, Dunsby C, Lanigan PMP, Munro I, Benninger RKP, de Beule P, Auksorius E, Hegyi L, Sandison A, Wallace A, Soutter P, Neil MAA, Lever J, Stamp GW, French PMW. Multidimensional Fluorescence Imaging Applied to Biological Tissue. REVIEWS IN FLUORESCENCE 2006 2006. [DOI: 10.1007/0-387-33016-x_22] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
|
22
|
RAMANUJAN VKRISHNAN, ZHANG JIANHUA, CENTONZE VICTORIAE, HERMAN BRIAN. Streak Fluorescence Lifetime Imaging Microscopy: A Novel Technology for Quantitative FRET Imaging. Mol Imaging 2005. [DOI: 10.1016/b978-019517720-6.50021-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
|
23
|
|
24
|
Abstract
We describe the theory and implementation of a frequency-domain fluorescence lifetime confocal microscope using switched diode laser illumination. Standard, communications-type, radio-frequency electronics are used to provide inexpensive modulation references and to perform phase-sensitive detection. This allows the rapid acquisition of fluorescence intensity and lifetime images and their display in real time. We show fluorescence lifetime images of bead objects and fluorescence lifetime images of biological specimens from a single confocal scan.
Collapse
Affiliation(s)
- M J Booth
- Department of Engineering Science, University of Oxford, Parks Road, Oxford OX1 3PJ, UK.
| | | |
Collapse
|
25
|
Becker W, Bergmann A, Hink MA, König K, Benndorf K, Biskup C. Fluorescence lifetime imaging by time-correlated single-photon counting. Microsc Res Tech 2004; 63:58-66. [PMID: 14677134 DOI: 10.1002/jemt.10421] [Citation(s) in RCA: 269] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
We present a time-correlated single photon counting (TCPSC) technique that allows time-resolved multi-wavelength imaging in conjunction with a laser scanning microscope and a pulsed excitation source. The technique is based on a four-dimensional histogramming process that records the photon density over the time of the fluorescence decay, the x-y coordinates of the scanning area, and the wavelength. The histogramming process avoids any time gating or wavelength scanning and, therefore, yields a near-perfect counting efficiency. The time resolution is limited only by the transit time spread of the detector. The technique can be used with almost any confocal or two-photon laser scanning microscope and works at any scanning rate. We demonstrate the application to samples stained with several dyes and to CFP-YFP FRET.
Collapse
Affiliation(s)
- W Becker
- Becker & Hickl GmbH, D-12277 Berlin, Germany.
| | | | | | | | | | | |
Collapse
|