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Lightley J, Kumar S, Lim MQ, Garcia E, Görlitz F, Alexandrov Y, Parrado T, Hollick C, Steele E, Roßmann K, Graham J, Broichhagen J, McNeish IA, Roufosse CA, Neil MAA, Dunsby C, French PMW. openFrame: A modular, sustainable, open microscopy platform with single-shot, dual-axis optical autofocus module providing high precision and long range of operation. J Microsc 2023; 292:64-77. [PMID: 37616077 PMCID: PMC10953376 DOI: 10.1111/jmi.13219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 08/04/2023] [Accepted: 08/21/2023] [Indexed: 08/25/2023]
Abstract
'openFrame' is a modular, low-cost, open-hardware microscopy platform that can be configured or adapted to most light microscopy techniques and is easily upgradeable or expandable to multiple modalities. The ability to freely mix and interchange both open-source and proprietary hardware components or software enables low-cost, yet research-grade instruments to be assembled and maintained. It also enables rapid prototyping of advanced or novel microscope systems. For long-term time-lapse image data acquisition, slide-scanning or high content analysis, we have developed a novel optical autofocus incorporating orthogonal cylindrical optics to provide robust single-shot closed-loop focus lock, which we have demonstrated to accommodate defocus up to ±37 μm with <200 nm accuracy, and a two-step autofocus mode which we have shown can operate with defocus up to ±68 μm. We have used this to implement automated single molecule localisation microscopy (SMLM) in a relatively low-cost openFrame-based instrument using multimode diode lasers for excitation and cooled CMOS cameras.
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Affiliation(s)
- J. Lightley
- Photonics Group, Physics DepartmentImperial College LondonLondonUK
- Francis Crick InstituteLondonUK
| | - S. Kumar
- Photonics Group, Physics DepartmentImperial College LondonLondonUK
- Francis Crick InstituteLondonUK
| | - M. Q. Lim
- Photonics Group, Physics DepartmentImperial College LondonLondonUK
- Department of Surgery and CancerImperial College LondonLondonUK
| | - E. Garcia
- Photonics Group, Physics DepartmentImperial College LondonLondonUK
- Department of Surgery and CancerImperial College LondonLondonUK
| | - F. Görlitz
- Photonics Group, Physics DepartmentImperial College LondonLondonUK
| | - Y. Alexandrov
- Photonics Group, Physics DepartmentImperial College LondonLondonUK
- Francis Crick InstituteLondonUK
| | | | | | - E. Steele
- Cairn Research LtdFavershamKentEngland
| | - K. Roßmann
- Leibniz‐Forschungsinstitut für Molekulare PharmakologieBerlinGermany
| | - J. Graham
- Cairn Research LtdFavershamKentEngland
| | - J. Broichhagen
- Leibniz‐Forschungsinstitut für Molekulare PharmakologieBerlinGermany
| | - I. A. McNeish
- Department of Surgery and CancerImperial College LondonLondonUK
| | - C. A. Roufosse
- Department of Inflammation and ImmunologyImperial College LondonLondonUK
| | - M. A. A. Neil
- Photonics Group, Physics DepartmentImperial College LondonLondonUK
- Francis Crick InstituteLondonUK
| | - C. Dunsby
- Photonics Group, Physics DepartmentImperial College LondonLondonUK
- Francis Crick InstituteLondonUK
| | - P. M. W. French
- Photonics Group, Physics DepartmentImperial College LondonLondonUK
- Francis Crick InstituteLondonUK
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Dvinskikh L, Sparks H, Brito L, MacLeod KT, Harding SE, Dunsby C. Remote-refocusing light-sheet fluorescence microscopy enables 3D imaging of electromechanical coupling of hiPSC-derived and adult cardiomyocytes in co-culture. Sci Rep 2023; 13:3342. [PMID: 36849727 PMCID: PMC9970973 DOI: 10.1038/s41598-023-29419-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Accepted: 02/03/2023] [Indexed: 03/01/2023] Open
Abstract
Improving cardiac function through stem-cell regenerative therapy requires functional and structural integration of the transplanted cells with the host tissue. Visualizing the electromechanical interaction between native and graft cells necessitates 3D imaging with high spatio-temporal resolution and low photo-toxicity. A custom light-sheet fluorescence microscope was used for volumetric imaging of calcium dynamics in co-cultures of adult rat left ventricle cardiomyocytes and human induced pluripotent stem cell-derived cardiomyocytes. Aberration-free remote refocus of the detection plane synchronously to the scanning of the light sheet along the detection axis enabled fast dual-channel 3D imaging at subcellular resolution without mechanical sample disturbance at up to 8 Hz over a ∼300 µm × 40 µm × 50 µm volume. The two cell types were found to undergo electrically stimulated and spontaneous synchronized calcium transients and contraction. Electromechanical coupling improved with co-culture duration, with 50% of adult-CM coupled after 24 h of co-culture, compared to 19% after 4 h (p = 0.0305). Immobilization with para-nitroblebbistatin did not prevent calcium transient synchronization, with 35% and 36% adult-CM coupled in control and treated samples respectively (p = 0.91), indicating that electrical coupling can be maintained independently of mechanotransduction.
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Affiliation(s)
- L Dvinskikh
- Department of Physics, Imperial College London, London, UK. .,National Heart and Lung Institute, Imperial College London, London, UK. .,Department of Chemistry, Imperial College London, London, UK.
| | - H Sparks
- Department of Physics, Imperial College London, London, UK
| | - L Brito
- National Heart and Lung Institute, Imperial College London, London, UK
| | - K T MacLeod
- National Heart and Lung Institute, Imperial College London, London, UK
| | - S E Harding
- National Heart and Lung Institute, Imperial College London, London, UK
| | - C Dunsby
- Department of Physics, Imperial College London, London, UK
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Munro I, García E, Yan M, Guldbrand S, Kumar S, Kwakwa K, Dunsby C, Neil MAA, French PMW. Accelerating single molecule localization microscopy through parallel processing on a high-performance computing cluster. J Microsc 2018; 273:148-160. [PMID: 30508256 PMCID: PMC6378585 DOI: 10.1111/jmi.12772] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Revised: 11/14/2018] [Accepted: 11/18/2018] [Indexed: 12/25/2022]
Abstract
Super‐resolved microscopy techniques have revolutionized the ability to study biological structures below the diffraction limit. Single molecule localization microscopy (SMLM) techniques are widely used because they are relatively straightforward to implement and can be realized at relatively low cost, e.g. compared to laser scanning microscopy techniques. However, while the data analysis can be readily undertaken using open source or other software tools, large SMLM data volumes and the complexity of the algorithms used often lead to long image data processing times that can hinder the iterative optimization of experiments. There is increasing interest in high throughput SMLM, but its further development and application is inhibited by the data processing challenges. We present here a widely applicable approach to accelerating SMLM data processing via a parallelized implementation of ThunderSTORM on a high‐performance computing (HPC) cluster and quantify the speed advantage for a four‐node cluster (with 24 cores and 128 GB RAM per node) compared to a high specification (28 cores, 128 GB RAM, SSD‐enabled) desktop workstation. This data processing speed can be readily scaled by accessing more HPC resources. Our approach is not specific to ThunderSTORM and can be adapted for a wide range of SMLM software. Lay Description Optical microscopy is now able to provide images with a resolution far beyond the diffraction limit thanks to relatively new super‐resolved microscopy (SRM) techniques, which have revolutionized the ability to study biological structures. One approach to SRM is to randomly switch on and off the emission of fluorescent molecules in an otherwise conventional fluorescence microscope. If only a sparse subset of the fluorescent molecules labelling a sample can be switched on at a time, then each emitter will be, on average, spaced further apart than the diffraction‐limited resolution of the conventional microscope and the separate bright spots in the image corresponding to each emitter can be localised to high precision by finding the centre of each feature using a computer program. Thus, a precise map of the emitter positions can be recorded by sequentially mapping the localisation of different subsets of emitters as they are switched on and others switched off. Typically, this approach, described as single molecule localisation microscopy (SMLM), results in large image data sets that can take many minutes to hours to process, depending on the size of the field of view and whether the SMLM analysis employs a computationally‐intensive iterative algorithm. Such a slow workflow makes it difficult to optimise experiments and to analyse large numbers of samples. Faster SMLM experiments would be generally useful and automated high throughput SMLM studies of arrays of samples, such as cells, could be applied to drug discovery and other applications. However, the time required to process the resulting data would be prohibitive on a normal computer. To address this, we have developed a method to run standard SMLM data analysis software tools in parallel on a high‐performance computing cluster (HPC). This can be used to accelerate the analysis of individual SMLM experiments or it can be scaled to analyse high throughput SMLM data by extending it to run on an arbitrary number of HPC processors in parallel. In this paper we outline the design of our parallelised SMLM software for HPC and quantify the speed advantage when implementing it on four HPC nodes compared to a powerful desktop computer.
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Affiliation(s)
- I Munro
- Photonics Group, Physics Department, Imperial College London, London, U.K
| | - E García
- Photonics Group, Physics Department, Imperial College London, London, U.K
| | - M Yan
- Photonics Group, Physics Department, Imperial College London, London, U.K.,Northwest Institute of Nuclear Technology, Xi'an, Shaanxi, P.R. China
| | - S Guldbrand
- Photonics Group, Physics Department, Imperial College London, London, U.K
| | - S Kumar
- Photonics Group, Physics Department, Imperial College London, London, U.K.,The Francis Crick Institute, London, U.K
| | - K Kwakwa
- Photonics Group, Physics Department, Imperial College London, London, U.K
| | - C Dunsby
- Photonics Group, Physics Department, Imperial College London, London, U.K.,Centre for Pathology, Imperial College London, London, U.K
| | - M A A Neil
- Photonics Group, Physics Department, Imperial College London, London, U.K
| | - P M W French
- Photonics Group, Physics Department, Imperial College London, London, U.K
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Sparks H, Görlitz F, Kelly DJ, Warren SC, Kellett PA, Garcia E, Dymoke-Bradshaw AKL, Hares JD, Neil MAA, Dunsby C, French PMW. Characterisation of new gated optical image intensifiers for fluorescence lifetime imaging. Rev Sci Instrum 2017; 88:013707. [PMID: 28147687 DOI: 10.1063/1.4973917] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
We report the characterisation of gated optical image intensifiers for fluorescence lifetime imaging, evaluating the performance of several different prototypes that culminate in a new design that provides improved spatial resolution conferred by the addition of a magnetic field to reduce the lateral spread of photoelectrons on their path between the photocathode and microchannel plate, and higher signal to noise ratio conferred by longer time gates. We also present a methodology to compare these systems and their capabilities, including the quantitative readouts of Förster resonant energy transfer.
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Affiliation(s)
- H Sparks
- Photonics Group, Department of Physics, Imperial College London, Prince Consort Road, London SW7 2BW, United Kingdom
| | - F Görlitz
- Photonics Group, Department of Physics, Imperial College London, Prince Consort Road, London SW7 2BW, United Kingdom
| | - D J Kelly
- Photonics Group, Department of Physics, Imperial College London, Prince Consort Road, London SW7 2BW, United Kingdom
| | - S C Warren
- Photonics Group, Department of Physics, Imperial College London, Prince Consort Road, London SW7 2BW, United Kingdom
| | - P A Kellett
- Kentech Instruments Ltd., Howbery Park, Wallingford OX10 8BD, United Kingdom
| | - E Garcia
- Photonics Group, Department of Physics, Imperial College London, Prince Consort Road, London SW7 2BW, United Kingdom
| | | | - J D Hares
- Kentech Instruments Ltd., Howbery Park, Wallingford OX10 8BD, United Kingdom
| | - M A A Neil
- Photonics Group, Department of Physics, Imperial College London, Prince Consort Road, London SW7 2BW, United Kingdom
| | - C Dunsby
- Photonics Group, Department of Physics, Imperial College London, Prince Consort Road, London SW7 2BW, United Kingdom
| | - P M W French
- Photonics Group, Department of Physics, Imperial College London, Prince Consort Road, London SW7 2BW, United Kingdom
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Dyer BT, Elder JM, Lagarto J, Harding SE, French PMW, Peters NS, Dunsby C, Lyon AR. 165 Label-free autofluorescence lifetime to assess changes in myocardial fibrosis and metabolism in vivoin a doxorubicin cardiomyopathy heart failure model. Heart 2015. [DOI: 10.1136/heartjnl-2015-308066.165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Gore DM, French P, O'Brart D, Dunsby C, Allan BD. Two-Photon Fluorescence Microscopy of Corneal Riboflavin Absorption Through an Intact Epithelium. Invest Ophthalmol Vis Sci 2015; 56:1191-2. [DOI: 10.1167/iovs.15-16457] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Dyer BT, Lagarto J, French P, Peters NS, Dunsby C, Lyon AR. TIME-RESOLVED AUTOFLUORESCENCE SPECTROSCOPY AS LABEL-FREE METHOD TO CHARACTERISE ACUTE CHANGES IN EX VIVO MODELS OF CARDIAC DISEASE. Heart 2014. [DOI: 10.1136/heartjnl-2014-306916.38] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Viessmann OM, Eckersley RJ, Christensen-Jeffries K, Tang MX, Dunsby C. Acoustic super-resolution with ultrasound and microbubbles. Phys Med Biol 2013; 58:6447-58. [DOI: 10.1088/0031-9155/58/18/6447] [Citation(s) in RCA: 165] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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Abstract
Recently there have been significant advances in developing hybrid techniques combining electromagnetic waves with ultrasound for biomedical imaging, namely photoacoustic, thermoacoustic, and acousto-optic (or ultrasound modulated optical) tomography. All three techniques take advantage of tissue contrast offered by electromagnetic (EM) waves, while achieving good spatial resolution in deeper tissue facilitated by ultrasound. In this review the principles of the three techniques are introduced. A description of existing experimental and image reconstruction techniques is provided. Some recent key developments are highlighted and current issues in each of the areas are discussed.
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Affiliation(s)
- M-X Tang
- Department of Bioengineering, Imperial College London, London, UK
| | - D S Elson
- Institute of Biomedical Engineering, Imperial College London, London, UK
| | - R Li
- Department of Bioengineering, Imperial College London, London, UK
| | - C Dunsby
- Department of Physics, Imperial College London, London, UK
| | - R J Eckersley
- Imaging Sciences Department, Imperial College London, London, UK
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10
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Abstract
This paper describes a new optically sectioning microscopy technique based on oblique selective plane illumination combined with oblique imaging. This method differs from previous selective plane illumination techniques as the same high numerical aperture lens is used to both illuminate and image the specimen. Initial results obtained using fluorescent pollen grains are presented, together with a measurement of the resolution of the system and an analysis of the potential performance of future systems. Since only the plane of the specimen that is being imaged is illuminated, this technique is particularly suited to time-lapse 3-D imaging of sensitive biological systems where photobleaching and phototoxicity must be kept to a minimum, and it could also be applied to image microfluidic technology for lab-on-a-chip, cytometry and other applications.
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Affiliation(s)
- C Dunsby
- Photonics Group, Department of Physics, Imperial College London, South Kensington Campus, London, SW7 2AZ, UK.
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11
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Galletly N, McGinty J, Dunsby C, Teixeira F, Requejo-Isidro J, Munro I, Elson D, Neil M, Chu A, French P, Stamp G. Fluorescence lifetime imaging distinguishes basal cell carcinoma from surrounding uninvolved skin. Br J Dermatol 2008; 159:152-61. [DOI: 10.1111/j.1365-2133.2008.08577.x] [Citation(s) in RCA: 112] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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12
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De Beule PAA, Dunsby C, Galletly NP, Stamp GW, Chu AC, Anand U, Anand P, Benham CD, Naylor A, French PMW. A hyperspectral fluorescence lifetime probe for skin cancer diagnosis. Rev Sci Instrum 2007; 78:123101. [PMID: 18163714 DOI: 10.1063/1.2818785] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
The autofluorescence of biological tissue can be exploited for the detection and diagnosis of disease but, to date, its complex nature and relatively weak signal levels have impeded its widespread application in biology and medicine. We present here a portable instrument designed for the in situ simultaneous measurement of autofluorescence emission spectra and temporal decay profiles, permitting the analysis of complex fluorescence signals. This hyperspectral fluorescence lifetime probe utilizes two ultrafast lasers operating at 355 and 440 nm that can excite autofluorescence from many different biomolecules present in skin tissue including keratin, collagen, nicotinamide adenine dinucleotide (phosphate), and flavins. The instrument incorporates an optical fiber probe to provide sample illumination and fluorescence collection over a millimeter-sized area. We present a description of the system, including spectral and temporal characterizations, and report the preliminary application of this instrument to a study of recently resected (<2 h) ex vivo skin lesions, illustrating its potential for skin cancer detection and diagnosis.
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Affiliation(s)
- P A A De Beule
- Department of Physics, Imperial College London, South Kensington, London SW7 2AZ, United Kingdom
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Grant DM, McGinty J, McGhee EJ, Bunney TD, Owen DM, Talbot CB, Zhang W, Kumar S, Munro I, Lanigan PM, Kennedy GT, Dunsby C, Magee AI, Courtney P, Katan M, Neil MAA, French PMW. High speed optically sectioned fluorescence lifetime imaging permits study of live cell signaling events. Opt Express 2007; 15:15656-73. [PMID: 19550853 DOI: 10.1364/oe.15.015656] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
We present a time domain optically sectioned fluorescence lifetime imaging (FLIM) microscope developed for high-speed live cell imaging. This single photon excited system combines wide field parallel pixel detection with confocal sectioning utilizing spinning Nipkow disc microscopy. It can acquire fluorescence lifetime images of live cells at up to 10 frames per second (fps), permitting high-speed FLIM of cell dynamics and protein interactions with potential for high throughput cell imaging and screening applications. We demonstrate the application of this FLIM microscope to real-time monitoring of changes in lipid order in cell membranes following cholesterol depletion using cyclodextrin and to the activation of the small GTP-ase Ras in live cells using FRET.
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14
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Kumar S, Dunsby C, De Beule PAA, Owen DM, Anand U, Lanigan PMP, Benninger RKP, Davis DM, Neil MAA, Anand P, Benham C, Naylor A, French PMW. Multifocal multiphoton excitation and time correlated single photon counting detection for 3-D fluorescence lifetime imaging. Opt Express 2007; 15:12548-61. [PMID: 19550524 DOI: 10.1364/oe.15.012548] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
We report a multifocal multiphoton time-correlated single photon counting (TCSPC) fluorescence lifetime imaging (FLIM) microscope system that uses a 16 channel multi-anode PMT detector. Multiphoton excitation minimizes out-of-focus photobleaching, multifocal excitation reduces non-linear in-plane photobleaching effects and TCSPC electronics provide photon-efficient detection of the fluorescence decay profile. TCSPC detection is less prone to bleaching- and movement-induced artefacts compared to wide-field time-gated or frequency-domain FLIM. This microscope is therefore capable of acquiring 3-D FLIM images at significantly increased speeds compared to single beam multiphoton microscopy and we demonstrate this with live cells expressing a GFP tagged protein. We also apply this system to time-lapse FLIM of NAD(P)H autofluorescence in single live cells and report measurements on the change in the fluorescence decay profile following the application of a known metabolic inhibitor.
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15
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Grant DM, Elson DS, Schimpf D, Dunsby C, Requejo-Isidro J, Auksorius E, Munro I, Neil MAA, French PMW, Nye E, Stamp G, Courtney P. Optically sectioned fluorescence lifetime imaging using a Nipkow disk microscope and a tunable ultrafast continuum excitation source. Opt Lett 2005; 30:3353-5. [PMID: 16389829 DOI: 10.1364/ol.30.003353] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
We demonstrate an optically sectioned fluorescence lifetime imaging microscope with a wide-field detector, using a convenient, continuously tunable (435-1150 nm) ultrafast source for fluorescence imaging applications that is derived from a visible supercontinuum generated in a microstructured fiber.
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Affiliation(s)
- D M Grant
- Physics Department, Imperial College London, Prince Consort Road, London SW7 2BW, UK
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16
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Munro I, McGinty J, Galletly N, Requejo-Isidro J, Lanigan PMP, Elson DS, Dunsby C, Neil MAA, Lever MJ, Stamp GWH, French PMW. Toward the clinical application of time-domain fluorescence lifetime imaging. J Biomed Opt 2005; 10:051403. [PMID: 16292940 DOI: 10.1117/1.2102807] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
High-speed (video-rate) fluorescence lifetime imaging (FLIM) through a flexible endoscope is reported based on gated optical image intensifier technology. The optimization and potential application of FLIM to tissue autofluorescence for clinical applications are discussed.
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Affiliation(s)
- I Munro
- Imperial College London, Physics Department, Photonics Group, South Kensington Campus, London SW7 2AZ.
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