1
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Alexander E, Lee B, Pham D, Garcia-Rodriguez S, Gryczynski Z, Gryczynski I. Photophysical properties of DAPI in PVA films. Possibility of room temperature phosphorescence. Anal Biochem 2024; 689:115498. [PMID: 38423238 DOI: 10.1016/j.ab.2024.115498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Revised: 02/09/2024] [Accepted: 02/26/2024] [Indexed: 03/02/2024]
Abstract
We studied the spectral properties of 4'-6-diamidino-2-phenylindole (DAPI) in poly (vinyl alcohol) (PVA) films. Absorption and fluorescence spectra, emission and excitation spectra, quantum yield, and fluorescence lifetime have been characterized. An efficient room temperature phosphorescence (RTP) of DAPI has been observed with UV and blue light excitations. A few hundred millisecond phosphorescence lifetime enables a gated detection with sufficient background reduction. We found the phosphorescent Quantum Yield of DAPI in PVA Film to be 0.0009.
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Affiliation(s)
- Emma Alexander
- Department of Physics and Astronomy, Texas Christian University, Fort Worth, TX, 76129, USA.
| | - Bong Lee
- Department of Physics and Astronomy, Texas Christian University, Fort Worth, TX, 76129, USA
| | - Danh Pham
- Department of Physics and Astronomy, Texas Christian University, Fort Worth, TX, 76129, USA
| | | | - Zygmunt Gryczynski
- Department of Physics and Astronomy, Texas Christian University, Fort Worth, TX, 76129, USA
| | - Ignacy Gryczynski
- Department of Physics and Astronomy, Texas Christian University, Fort Worth, TX, 76129, USA
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2
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Luu P, Fraser SE, Schneider F. More than double the fun with two-photon excitation microscopy. Commun Biol 2024; 7:364. [PMID: 38531976 DOI: 10.1038/s42003-024-06057-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Accepted: 03/15/2024] [Indexed: 03/28/2024] Open
Abstract
For generations researchers have been observing the dynamic processes of life through the lens of a microscope. This has offered tremendous insights into biological phenomena that span multiple orders of time- and length-scales ranging from the pure magic of molecular reorganization at the membrane of immune cells, to cell migration and differentiation during development or wound healing. Standard fluorescence microscopy techniques offer glimpses at such processes in vitro, however, when applied in intact systems, they are challenged by reduced signal strengths and signal-to-noise ratios that result from deeper imaging. As a remedy, two-photon excitation (TPE) microscopy takes a special place, because it allows us to investigate processes in vivo, in their natural environment, even in a living animal. Here, we review the fundamental principles underlying TPE aimed at basic and advanced microscopy users interested in adopting TPE for intravital imaging. We focus on applications in neurobiology, present current trends towards faster, wider and deeper imaging, discuss the combination with photon counting technologies for metabolic imaging and spectroscopy, as well as highlight outstanding issues and drawbacks in development and application of these methodologies.
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Affiliation(s)
- Peter Luu
- Translational Imaging Center, Michelson Center for Convergent Bioscience, University of Southern California, Los Angeles, CA, 90089, USA
- Department of Biological Sciences, Division of Molecular and Computational Biology, University of Southern California, Los Angeles, CA, 90089, USA
| | - Scott E Fraser
- Translational Imaging Center, Michelson Center for Convergent Bioscience, University of Southern California, Los Angeles, CA, 90089, USA
- Department of Biological Sciences, Division of Molecular and Computational Biology, University of Southern California, Los Angeles, CA, 90089, USA
- Alfred Mann Department of Biomedical Engineering, University of Southern California, Los Angeles, CA, 90089, USA
| | - Falk Schneider
- Translational Imaging Center, Michelson Center for Convergent Bioscience, University of Southern California, Los Angeles, CA, 90089, USA.
- Dana and David Dornsife College of Letters, Arts and Sciences, University of Southern California, Los Angeles, CA, 90089, USA.
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3
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Multi-Color Two-Photon Microscopic Imaging Based on a Single-Wavelength Excitation. BIOSENSORS 2022; 12:bios12050307. [PMID: 35624608 PMCID: PMC9138471 DOI: 10.3390/bios12050307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Revised: 05/02/2022] [Accepted: 05/04/2022] [Indexed: 11/17/2022]
Abstract
Two-photon probes with broad absorption spectra are beneficial for multi-color two-photon microscopy imaging, which is one of the most powerful tools to study the dynamic processes of living cells. To achieve multi-color two-photon imaging, multiple lasers and detectors are usually required for excitation and signal collection, respectively. However, one makes the imaging system more complicated and costly. Here, we demonstrate a multi-color two-photon imaging method with a single-wavelength excitation by using a signal separation strategy. The method can effectively solve the problem of spectral crosstalk by selecting a suitable filter combination and applying image subtraction. The experimental results show that the two-color and three-color two-photon imaging are achieved with a single femtosecond laser. Furthermore, this method can also be combined with multi-photon imaging technology to reveal more information and interaction in thick biological tissues.
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4
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Mukherjee S, Rananaware P, Brahmkhatri V, Mishra M. Polyvinylpyrrolidone-Curcumin Nanoconjugate as a Biocompatible, Non-toxic Material for Biological Applications. J CLUST SCI 2022. [DOI: 10.1007/s10876-022-02230-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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5
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Du Le VN, Saytashev I, Saha S, Lopez PF, Laughrey M, Ramella-Roman JC. Depth-resolved Mueller matrix polarimetry microscopy of the rat cornea. BIOMEDICAL OPTICS EXPRESS 2020; 11:5982-5994. [PMID: 33150000 PMCID: PMC7587284 DOI: 10.1364/boe.402201] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 09/15/2020] [Accepted: 09/21/2020] [Indexed: 05/31/2023]
Abstract
Mueller matrix polarimetry (MMP) is a promising linear imaging modality that can enable visualization and measurement of the polarization properties of the cornea. Although the distribution of corneal birefringence has been reported, depth resolved MMP imaging of the cornea has not been archived and remains challenging. In this work, we perform depth-resolved imaging of the cornea using an improved system that combines Mueller matrix reflectance and transmission microscopy together with nonlinear microscopy utilizing second harmonic generation (SHG) and two photon excitation fluorescence (TPEF). We show that TPEF can reveal corneal epithelial cellular network while SHG can highlight the presence of corneal stromal lamellae. We then demonstrate that, in confocal reflectance measurement, as depth increases from 0 to 80 μm both corneal depolarization and retardation increase. Furthermore, it is shown that the spatial distribution of corneal depolarization and retardation displays similar complexity in both reflectance (confocal and non-confocal) and transmission measurement, likely due to the strong degree of heterogeneity in the stromal lamellae.
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Affiliation(s)
- V N Du Le
- Department of Biomedical Engineering, College of Engineering and Computing, Florida International University, 10555 West Flagler Street, Miami, FL 33174, USA
| | - Ilyas Saytashev
- Department of Ophthalmology, Herbert Wertheim College of Medicine, Florida International University, 11200 SW 8 Street, Miami, FL 33199, USA
| | - Sudipta Saha
- Department of Biomedical Engineering, College of Engineering and Computing, Florida International University, 10555 West Flagler Street, Miami, FL 33174, USA
| | - Pedro F Lopez
- Department of Ophthalmology, Herbert Wertheim College of Medicine, Florida International University, 11200 SW 8 Street, Miami, FL 33199, USA
| | - Megan Laughrey
- Department of Ophthalmology, Herbert Wertheim College of Medicine, Florida International University, 11200 SW 8 Street, Miami, FL 33199, USA
| | - Jessica C Ramella-Roman
- Department of Biomedical Engineering, College of Engineering and Computing, Florida International University, 10555 West Flagler Street, Miami, FL 33174, USA
- Department of Ophthalmology, Herbert Wertheim College of Medicine, Florida International University, 11200 SW 8 Street, Miami, FL 33199, USA
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6
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Benitez-Martin C, Li S, Dominguez-Alfaro A, Najera F, Pérez-Inestrosa E, Pischel U, Andréasson J. Toward Two-Photon Absorbing Dyes with Unusually Potentiated Nonlinear Fluorescence Response. J Am Chem Soc 2020; 142:14854-14858. [PMID: 32799520 PMCID: PMC7498150 DOI: 10.1021/jacs.0c07377] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
![]()
The
combination of two two-photon-induced processes in a Förster
resonance energy transfer (FRET)-operated photochromic fluorene-dithienylethene
dyad lays the foundation for the observation of a quartic dependence
of the fluorescence signal on the excitation light intensity. While
this photophysical behavior is predicted for a four-photon absorbing
dye, the herein proposed approach opens the way to use two-photon
absorbing dyes, reaching the same performance. Hence, the spatial
resolution limit, being a critical parameter for applications in fluorescence
imaging or data storage with common two-photon absorbing dyes, is
dramatically improved.
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Affiliation(s)
- Carlos Benitez-Martin
- Department of Chemistry and Chemical Engineering, Physical Chemistry, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden.,Universidad de Málaga-IBIMA, Departamento de Quı́mica Orgánica, Campus Teatinos s/n, E-29071 Málaga, Spain.,Centro Andaluz de Nanomedicina y Biotecnologı́a (BIONAND), Parque Tecnológico de Andalucı́a, C/Severo Ochoa 35, E-29590 Málaga, Spain
| | - Shiming Li
- Department of Chemistry and Chemical Engineering, Physical Chemistry, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden
| | - Antonio Dominguez-Alfaro
- CIQSO - Center for Research in Sustainable Chemistry and Department of Chemistry, University of Huelva, Campus de El Carmen s/n, E-21071 Huelva, Spain
| | - Francisco Najera
- Universidad de Málaga-IBIMA, Departamento de Quı́mica Orgánica, Campus Teatinos s/n, E-29071 Málaga, Spain.,Centro Andaluz de Nanomedicina y Biotecnologı́a (BIONAND), Parque Tecnológico de Andalucı́a, C/Severo Ochoa 35, E-29590 Málaga, Spain
| | - Ezequiel Pérez-Inestrosa
- Universidad de Málaga-IBIMA, Departamento de Quı́mica Orgánica, Campus Teatinos s/n, E-29071 Málaga, Spain.,Centro Andaluz de Nanomedicina y Biotecnologı́a (BIONAND), Parque Tecnológico de Andalucı́a, C/Severo Ochoa 35, E-29590 Málaga, Spain
| | - Uwe Pischel
- CIQSO - Center for Research in Sustainable Chemistry and Department of Chemistry, University of Huelva, Campus de El Carmen s/n, E-21071 Huelva, Spain
| | - Joakim Andréasson
- Department of Chemistry and Chemical Engineering, Physical Chemistry, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden
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7
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Vinegoni C, Feruglio PF, Gryczynski I, Mazitschek R, Weissleder R. Fluorescence anisotropy imaging in drug discovery. Adv Drug Deliv Rev 2019; 151-152:262-288. [PMID: 29410158 PMCID: PMC6072632 DOI: 10.1016/j.addr.2018.01.019] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Revised: 01/29/2018] [Accepted: 01/30/2018] [Indexed: 12/15/2022]
Abstract
Non-invasive measurement of drug-target engagement can provide critical insights in the molecular pharmacology of small molecule drugs. Fluorescence polarization/fluorescence anisotropy measurements are commonly employed in protein/cell screening assays. However, the expansion of such measurements to the in vivo setting has proven difficult until recently. With the advent of high-resolution fluorescence anisotropy microscopy it is now possible to perform kinetic measurements of intracellular drug distribution and target engagement in commonly used mouse models. In this review we discuss the background, current advances and future perspectives in intravital fluorescence anisotropy measurements to derive pharmacokinetic and pharmacodynamic measurements in single cells and whole organs.
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Affiliation(s)
- Claudio Vinegoni
- Center for System Biology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA.
| | - Paolo Fumene Feruglio
- Center for System Biology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA; Department of Neurological, Biomedical and Movement Sciences, University of Verona, Verona, Italy
| | - Ignacy Gryczynski
- University of North Texas Health Science Center, Institute for Molecular Medicine, Fort Worth, TX, United States
| | - Ralph Mazitschek
- Center for System Biology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Ralph Weissleder
- Center for System Biology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
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8
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Yahav G, Barnoy E, Roth N, Turgeman L, Fixler D. Reference-independent wide field fluorescence lifetime measurements using Frequency-Domain (FD) technique based on phase and amplitude crossing point. JOURNAL OF BIOPHOTONICS 2017; 10:1198-1207. [PMID: 27774782 DOI: 10.1002/jbio.201600220] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2016] [Revised: 09/29/2016] [Accepted: 09/30/2016] [Indexed: 06/06/2023]
Abstract
Fluorescence lifetime imaging microscopy (FLIM) is an essential tool in many scientific fields such as biology and medicine thanks to the known advantages of the fluorescence lifetime (FLT) over the classical fluorescence intensity (FI). However, the frequency domain (FD) FLIM technique suffers from its strong dependence on the reference and its compliance to the sample. In this paper, we suggest a new way to calculate the FLT by using the crossing point (CRPO) between the modulation and phase FLTs measured over several light emitting diode (LED) DC currents values instead of either method alone. This new technique was validated by measuring homogeneous substances with known FLT, where the CRPO appears to be the optimal measuring point. Furthermore, the CRPO method was applied in heterogeneous samples. It was found that the CRPO in known mixed solutions is the weighted average of the used solutions. While measuring B16 and lymphocyte cells, the CRPO of the DAPI compound in single FLT regions was measured at 3.5 ± 0.06 ns and at 2.83 ± 0.07 ns, respectively, both of which match previous reports and multi-frequency analyses. This paper suggests the CRPO as a new method to extract the FLT in problematic cases such as high MCP gains and heterogeneous environments. In traditional FD FLIM measurements, the variation in phase angle and modulation are measured. By measuring over varying DC currents, another variation is detected in the FLT determined through the phase and modulation methods, with the CRPO indicating the true FLT.
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Affiliation(s)
- Gilad Yahav
- Faculty of Engineering and the Institute of Nanotechnology and Advanced Materials, Bar Ilan University, 5290002, Ramat Gan, Israel
| | - Eran Barnoy
- Faculty of Engineering and the Institute of Nanotechnology and Advanced Materials, Bar Ilan University, 5290002, Ramat Gan, Israel
| | - Nir Roth
- Faculty of Engineering and the Institute of Nanotechnology and Advanced Materials, Bar Ilan University, 5290002, Ramat Gan, Israel
| | - Lior Turgeman
- Joseph M. Katz Graduate School of Business, University of Pittsburgh, Roberto Clemente Dr, PA, 15260, Pittsburgh, USA
| | - Dror Fixler
- Faculty of Engineering and the Institute of Nanotechnology and Advanced Materials, Bar Ilan University, 5290002, Ramat Gan, Israel
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9
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Zurbuchen MA, Lake MP, Kohan SA, Leung B, Bouchard LS. Nanodiamond landmarks for subcellular multimodal optical and electron imaging. Sci Rep 2014; 3:2668. [PMID: 24036840 PMCID: PMC3773618 DOI: 10.1038/srep02668] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2013] [Accepted: 08/30/2013] [Indexed: 11/09/2022] Open
Abstract
There is a growing need for biolabels that can be used in both optical and electron microscopies, are non-cytotoxic, and do not photobleach. Such biolabels could enable targeted nanoscale imaging of sub-cellular structures, and help to establish correlations between conjugation-delivered biomolecules and function. Here we demonstrate a sub-cellular multi-modal imaging methodology that enables localization of inert particulate probes, consisting of nanodiamonds having fluorescent nitrogen-vacancy centers. These are functionalized to target specific structures, and are observable by both optical and electron microscopies. Nanodiamonds targeted to the nuclear pore complex are rapidly localized in electron-microscopy diffraction mode to enable "zooming-in" to regions of interest for detailed structural investigations. Optical microscopies reveal nanodiamonds for in-vitro tracking or uptake-confirmation. The approach is general, works down to the single nanodiamond level, and can leverage the unique capabilities of nanodiamonds, such as biocompatibility, sensitive magnetometry, and gene and drug delivery.
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Affiliation(s)
- Mark A Zurbuchen
- 1] Department of Materials Science and Engineering [2] California NanoSystems Institute [3] Western Institute of Nanoelectronics, Department of Electrical Engineering
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10
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Zhang MY, Xu C, Lin CS, Guan X, Cheng WD. Theoretical study of the proton transfer wires influence on the one- and two-photon absorption properties of green fluorescent protein chromophore. Org Biomol Chem 2013; 11:1414-22. [PMID: 23338242 DOI: 10.1039/c2ob26914g] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The excited-state proton transfer (ESPT) via proton transfer wires in green fluorescent protein (GFP) plays an important role on the spectroscopic of GFP. In this work, we use the proton transfer wires and the chromophore complex to simulate the tautomer structures of neutral state and the intermediate state in wt-GFP. And we employ the time-dependent density functional theory combined with the sum-over-states method to calculate the one- and two-photon absorption properties of these complexes in GFP. We obtain the large stokes shift from 383 nm to 500 nm in GFP when simulating the ESPT process by these isomerous H-bonding complexes. We find that the TPA spectrum of the H-bonding complex of the intermediate state agrees more with experimental measurement than that of the H-bonding complex of the neutral state. The TPA spectrum of GFP might be mainly dominated by the structure which is similar to the H-bonding complex of intermediate state. Further, we simulate another kind of complex which possess short-strong hydrogen bonds in proton transfer wires, and find that TPA properties of these complexes are much stronger than that of the complexes with the long distance proton wires from GFP.
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Affiliation(s)
- Min-Yi Zhang
- State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, China
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11
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Olesiak-Banska J, Matczyszyn K, Zaleśny R, Murugan NA, Kongsted J, Ågren H, Bartkowiak W, Samoc M. Revealing Spectral Features in Two-Photon Absorption Spectrum of Hoechst 33342: A Combined Experimental and Quantum-Chemical Study. J Phys Chem B 2013; 117:12013-9. [DOI: 10.1021/jp407144k] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Joanna Olesiak-Banska
- Institute of Physical
and Theoretical Chemistry, Wrocław University of Technology, Wyb. Wyspiańskiego
27, PL-50370 Wrocław, Poland
| | - Katarzyna Matczyszyn
- Institute of Physical
and Theoretical Chemistry, Wrocław University of Technology, Wyb. Wyspiańskiego
27, PL-50370 Wrocław, Poland
| | - Robert Zaleśny
- Institute of Physical
and Theoretical Chemistry, Wrocław University of Technology, Wyb. Wyspiańskiego
27, PL-50370 Wrocław, Poland
- Division of Theoretical
Chemistry and Biology, School of Biotechnology, Royal Institute of Technology, SE-10691 Stockholm, Sweden
| | - N. Arul Murugan
- Division of Theoretical
Chemistry and Biology, School of Biotechnology, Royal Institute of Technology, SE-10691 Stockholm, Sweden
| | - Jacob Kongsted
- Department
of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Hans Ågren
- Division of Theoretical
Chemistry and Biology, School of Biotechnology, Royal Institute of Technology, SE-10691 Stockholm, Sweden
| | - Wojciech Bartkowiak
- Institute of Physical
and Theoretical Chemistry, Wrocław University of Technology, Wyb. Wyspiańskiego
27, PL-50370 Wrocław, Poland
| | - Marek Samoc
- Institute of Physical
and Theoretical Chemistry, Wrocław University of Technology, Wyb. Wyspiańskiego
27, PL-50370 Wrocław, Poland
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12
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Sasmal DK, Ghosh S, Das AK, Bhattacharyya K. Solvation dynamics of biological water in a single live cell under a confocal microscope. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2013; 29:2289-98. [PMID: 23336846 DOI: 10.1021/la3043473] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Time-resolved confocal microscopy has been applied to study the cytoplasm and nucleus region of a single live Chinese hamster ovary (CHO) cell. To select the cytoplasm and the nucleus region, two different fluorescent probes are used. A hydrophobic fluorescent dye, DCM, localizes preferentially in the cytoplasm region of a CHO cell. A DNA binding dye, DAPI, is found to be inside the nucleus of the cell. The locations of the probes are clearly seen in the image. Emission maxima of the dyes (DCM in cytoplasm and DAPI in the nucleus) are compared to those of the same dyes in different solvents. From this, it is concluded that the polarity (dielectric constant, ε) of the microenvironment of DCM in the cytoplasm is ~15. The nucleus is found to be much more polar with ε ≈ 60 (as reported by DAPI). The diffusion coefficient (and hence viscosity) in the cytoplasm and the nucleus was determined using fluorescence correlation spectroscopy (FCS). The diffusion coefficient (D(t)) of the dye (DCM) in the cytoplasm is 2 μm(2) s(-1) and is ~150 times slower than that in bulk water (buffer). D(t) of DAPI in the nucleus (15 μm(2) s(-1)) is 30 times slower than that in bulk water (buffer). The extremely slow diffusion inside the cell has been ascribed to higher viscosity and also to the binding of the probes (DCM and DAPI) to large biological macromolecules. The solvation dynamics of water in the cytoplasm (monitored by DCM) exhibits an average relaxation time [τ(sol)] of 1250 ± 50 ps, which is about 1000 times slower than in bulk water (1 ps). The solvation dynamics inside the nucleus (studied using DAPI) is about 2-fold faster, [τ(sol)] ≈ 775 ps. The higher polarity, faster diffusion, and faster solvation dynamics in the nucleus indicates that it is less crowded and less restricted than the cytoplasm.
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Affiliation(s)
- Dibyendu Kumar Sasmal
- Department of Physical Chemistry, Indian Association for the Cultivation of Science, Jadavpur, Kolkata, India
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13
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Alam MM, Chattopadhyaya M, Chakrabarti S, Ruud K. Effect of donor–acceptor orientation on solvent-dependent three-photon activity in through-space charge-transfer systems – case study of [2,2]-paracyclophane derivatives. Phys Chem Chem Phys 2013; 15:17570-6. [DOI: 10.1039/c3cp52696h] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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14
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Li L, Yuan N, Wang P, Wu Y, Song Y, Chen Z, He C. Three-photon absorption properties of a novel symmetrical Carbazole derivative having terminal 1,10-phenanthroline rings via carbon-nitrogen (C = N) double bond. J PHYS ORG CHEM 2012. [DOI: 10.1002/poc.2937] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Liang Li
- Shanghai Institute of Optics and Fine Mechanics; Chinese Academy of Sciences; No. 390, Qinghe Road, Jiading District Shanghai 201800 P. R. China
| | - Ningning Yuan
- Key Lab of Functional Inorganic Material Chemistry (Heilongjiang University); Ministry of Education; Harbin 150080 P. R. China
| | - Ping Wang
- Key Lab of Functional Inorganic Material Chemistry (Heilongjiang University); Ministry of Education; Harbin 150080 P. R. China
| | - Yiqun Wu
- Shanghai Institute of Optics and Fine Mechanics; Chinese Academy of Sciences; No. 390, Qinghe Road, Jiading District Shanghai 201800 P. R. China
- Key Lab of Functional Inorganic Material Chemistry (Heilongjiang University); Ministry of Education; Harbin 150080 P. R. China
| | - Yinglin Song
- Department of Applied Physics; Harbin Institute of Technology; Harbin 150080 P. R. China
| | - Zhimin Chen
- Key Lab of Functional Inorganic Material Chemistry (Heilongjiang University); Ministry of Education; Harbin 150080 P. R. China
| | - Chunying He
- Key Lab of Functional Inorganic Material Chemistry (Heilongjiang University); Ministry of Education; Harbin 150080 P. R. China
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15
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Spänig F, Haefele A, Castellano FN. Photoprocesses of Relevance to Supramolecular Chemistry. Supramol Chem 2012. [DOI: 10.1002/9780470661345.smc089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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16
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Schoonen WGEJ, Stevenson JCR, Westerink WMA, Horbach GJ. Cytotoxic effects of 109 reference compounds on rat H4IIE and human HepG2 hepatocytes. III: Mechanistic assays on oxygen consumption with MitoXpress and NAD(P)H production with Alamar Blue™. Toxicol In Vitro 2012; 26:511-25. [PMID: 22261204 DOI: 10.1016/j.tiv.2012.01.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2011] [Revised: 12/20/2011] [Accepted: 01/04/2012] [Indexed: 11/13/2022]
Abstract
In vitro toxicity screening can reduce the attrition rate of drug candidates in the pharmaceutical industry in the early development process. The focus in this study is to compare the sensitivity for cytotoxicity of a time-resolved fluoro metric oxygen probe with that of a fluoro metric Alamar Blue™ (AB) assay. Both assays measure mitochondrial activity by either oxygen consumption (LUX-A65N-1 (MitoXpress, Luxcel) probe) or NADH/FADH conversion (AB). Both assays were carried out with increasing concentrations of 109 reference compounds using rat H4IIE and human HepG2 hepatocytes at incubation periods of 24, 48 and 72 h. Prior to this study, the influence on medium with either glucose or galactose was studied to analyze the rate of glycolysis and oxygen consumption, which latter process may be impaired in hepatoma cells. Inhibitors of oxygen consumption in combination with a glucose up-take inhibitor showed the largest consumption rate differences in the presence of 5mM of glucose. The choice for the 109 reference compounds was based on the so-called Multicentre Evaluation for In vitro Cytotoxicity (MEIC) and on diverse drug categories. For 59 toxic reference compounds, an evaluation for both assays was carried up to 10(-3)M. Toxicity was demonstrated with MitoXpress for 23 (39%) and 36 (61%) compounds in H4IIE and HepG2 cells, respectively, and with AB for 44 (75%) and 40 (68%) compounds. For 50 more pharmaceutical drugs more physiological concentrations were used up to 3.16×10(-5)M, and only 19 (38%) of these compounds appeared to be toxic in both assays. In conclusion, overall 63 (58%) and 60 (55%) compounds showed toxic effects with the MitoXpress and AB assays on rat H4IIE and human HepG2 hepatocytes, respectively. AB assays were more sensitive with respect to H4IIE cells and MitoXpress assays with respect to HepG2 cells. At all tested time intervals, MitoXpress showed its sensitivity, while AB is more sensitive at 48 and 72 h. With AB more toxic compounds were identified, whereas MitoXpress was more sensitive for a few compounds. A species specific difference was clearly found with digoxin, a human specific potassium channel inhibitor. Thus both assays are valuable identifiers of early toxicity with discrimination in time, compounds and species.
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Affiliation(s)
- Willem G E J Schoonen
- Toxicology & Drug Disposition, Merck Research Laboratories, P.O. Box 20, 5340 BH Oss, The Netherlands.
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17
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Zhang MY, Wang JY, Lin CS, Cheng WD. First-principles study of one- and two-photon absorption of the H-bonding complexes from monomeric red fluorescent proteins with large Stokes shifts. J Phys Chem B 2011; 115:10750-7. [PMID: 21827203 DOI: 10.1021/jp203977m] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
LSSmKate1 and LSSmKate2 are monomeric red fluorescent proteins (RFPs) with large Stokes shifts (LSS). The hydrogen-bonding (H-bonding) network within LSSmKate1 or LSSmKate2, which is composed of a chromophore and some surrounding amino acid residues, supports their special spectral properties. In this work, we propose H-bonding complex models to simulate the H-bonding network of LSSmKate1 and LSSmKate2 and employ the time-dependent density functional theory combining with the sum-overstates method to calculate their one- and two-photon absorption characters. We discuss the influence of the hydrogen bond on the one- and two-photon absorption properties of these H-bonding complexes through intermolecular hyperconjugation of the hydrogen-bond form.
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Affiliation(s)
- Min-Yi Zhang
- State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, China
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18
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Leeder JM, Andrews DL. A molecular theory for two-photon and three-photon fluorescence polarization. J Chem Phys 2011; 134:094503. [PMID: 21384981 DOI: 10.1063/1.3556537] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
In the analysis of molecular structure and local order in heterogeneous samples, multiphoton excitation of fluorescence affords chemically specific information and high-resolution imaging. This report presents the results of an investigation that secures a detailed theoretical representation of the fluorescence polarization produced by one-, two-, and three-photon excitations, with orientational averaging procedures being deployed to deliver the fully disordered limits. The equations determining multiphoton fluorescence response prove to be expressible in a relatively simple, generic form, and graphs exhibit the functional form of the multiphoton fluorescence polarization. Amongst other features, the results lead to the identification of a condition under which the fluorescence produced through the concerted absorption of any number of photons becomes completely unpolarized. It is also shown that the angular variation of fluorescence intensities is reliable indicator of orientational disorder.
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Affiliation(s)
- J M Leeder
- School of Chemistry, University of East Anglia, Norwich NR4 7TJ, United Kingdom
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19
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Singh-Rachford TN, Castellano FN. Photon upconversion based on sensitized triplet–triplet annihilation. Coord Chem Rev 2010. [DOI: 10.1016/j.ccr.2010.01.003] [Citation(s) in RCA: 844] [Impact Index Per Article: 60.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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20
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Singh-Rachford TN, Castellano FN. Nonlinear Photochemistry Squared: Quartic Light Power Dependence Realized in Photon Upconversion. J Phys Chem A 2009; 113:9266-9. [DOI: 10.1021/jp906782g] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Tanya N. Singh-Rachford
- Department of Chemistry and Center for Photochemical Sciences, Bowling Green State University, Bowling Green, Ohio 43403
| | - Felix N. Castellano
- Department of Chemistry and Center for Photochemical Sciences, Bowling Green State University, Bowling Green, Ohio 43403
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21
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Tracing and ablation of single cells in the mammalian blastocyst using fluorescent DNA staining and multi-photon laser microscopy. Histochem Cell Biol 2008; 131:521-30. [DOI: 10.1007/s00418-008-0548-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/29/2008] [Indexed: 10/21/2022]
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22
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Sakadzić S, Demirbas U, Mempel TR, Moore A, Ruvinskaya S, Boas DA, Sennaroglu A, Kaertner FX, Fujimoto JG. Multi-photon microscopy with a low-cost and highly efficient Cr:LiCAF laser. OPTICS EXPRESS 2008; 16:20848-63. [PMID: 19065223 PMCID: PMC2689708 DOI: 10.1364/oe.16.020848] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Multi-photon microscopy (MPM) is a powerful tool for biomedical imaging, enabling molecular contrast and integrated structural and functional imaging on the cellular and subcellular level. However, the cost and complexity of femtosecond laser sources that are required in MPM are significant hurdles to widespread adoption of this important imaging modality. In this work, we describe femtosecond diode pumped Cr:LiCAF laser technology as a low cost alternative to femtosecond Ti:Sapphire lasers for MPM. Using single mode pump diodes which cost only $150 each, a diode pumped Cr:LiCAF laser generates approximately 70-fs duration, 1.8-nJ pulses at approximately 800 nm wavelengths, with a repetition rate of 100 MHz and average output power of 180 mW. Representative examples of MPM imaging in neuroscience, immunology, endocrinology and cancer research using Cr:LiCAF laser technology are presented. These studies demonstrate the potential of this laser source for use in a broad range of MPM applications.
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Affiliation(s)
- Sava Sakadzić
- MGH/MIT/HMS Athinuola A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital/Harvard Medical School, Charlestown, Massachusetts 02129, USA
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23
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Hemmilá I, Mukkala VM. Time-Resolution in Fluorometry Technologies, Labels, and Applications in Bioanalytical Assays. Crit Rev Clin Lab Sci 2008. [DOI: 10.1080/20014091084254] [Citation(s) in RCA: 194] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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24
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Abstract
This unit provides a detailed review and technical discussion of the principles of time-resolved fluorescence. The unique feature of this particular unit is that the principles are directly tied to the use of flow cytometry. There are a number of advantages in being able to discriminate between fluorochromes based upon their lifetimes as opposed to their emission wavelengths. One particularly good application is the determination of bound versus free molecules. The author covers both the theoretical and practical components of measuring fluorescence in the time domain. In addition, the unit provides a listing of the most common fluorescent dyes with comparative data of lifetime and excitation conditions.
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Affiliation(s)
- J A Steinkamp
- Bioscience Division, Los Alamos National Laboratory, Los Alamos, New Mexico, USA
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25
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Lin N, Ferrighi L, Zhao X, Ruud K, Rizzo A, Luo Y. Solvent Effects on the Three-Photon Absorption of a Symmetric Charge-Transfer Molecule. J Phys Chem B 2008; 112:4703-10. [DOI: 10.1021/jp7107522] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Na Lin
- Department of Theoretical Chemistry, School of Biotechnology, Royal Institute of Technology, SE-10691 Stockholm, Sweden, Centre for Theoretical and Computational Chemistry, Department of Chemistry, University of Tromsφ, N-9037 Tromsφ, Norway, Istituto per i Processi Chimico-Fisici del Consiglio Nazionale delle Ricerche (IPCF-CNR), Area della Ricerca di Pisa, Via G. Moruzzi 1, I-56124 Pisa, Italy, and Institute of Crystal Materials, Shandong University, 250100 Jinan, Shandong, People's Republic of China
| | - Lara Ferrighi
- Department of Theoretical Chemistry, School of Biotechnology, Royal Institute of Technology, SE-10691 Stockholm, Sweden, Centre for Theoretical and Computational Chemistry, Department of Chemistry, University of Tromsφ, N-9037 Tromsφ, Norway, Istituto per i Processi Chimico-Fisici del Consiglio Nazionale delle Ricerche (IPCF-CNR), Area della Ricerca di Pisa, Via G. Moruzzi 1, I-56124 Pisa, Italy, and Institute of Crystal Materials, Shandong University, 250100 Jinan, Shandong, People's Republic of China
| | - Xian Zhao
- Department of Theoretical Chemistry, School of Biotechnology, Royal Institute of Technology, SE-10691 Stockholm, Sweden, Centre for Theoretical and Computational Chemistry, Department of Chemistry, University of Tromsφ, N-9037 Tromsφ, Norway, Istituto per i Processi Chimico-Fisici del Consiglio Nazionale delle Ricerche (IPCF-CNR), Area della Ricerca di Pisa, Via G. Moruzzi 1, I-56124 Pisa, Italy, and Institute of Crystal Materials, Shandong University, 250100 Jinan, Shandong, People's Republic of China
| | - Kenneth Ruud
- Department of Theoretical Chemistry, School of Biotechnology, Royal Institute of Technology, SE-10691 Stockholm, Sweden, Centre for Theoretical and Computational Chemistry, Department of Chemistry, University of Tromsφ, N-9037 Tromsφ, Norway, Istituto per i Processi Chimico-Fisici del Consiglio Nazionale delle Ricerche (IPCF-CNR), Area della Ricerca di Pisa, Via G. Moruzzi 1, I-56124 Pisa, Italy, and Institute of Crystal Materials, Shandong University, 250100 Jinan, Shandong, People's Republic of China
| | - Antonio Rizzo
- Department of Theoretical Chemistry, School of Biotechnology, Royal Institute of Technology, SE-10691 Stockholm, Sweden, Centre for Theoretical and Computational Chemistry, Department of Chemistry, University of Tromsφ, N-9037 Tromsφ, Norway, Istituto per i Processi Chimico-Fisici del Consiglio Nazionale delle Ricerche (IPCF-CNR), Area della Ricerca di Pisa, Via G. Moruzzi 1, I-56124 Pisa, Italy, and Institute of Crystal Materials, Shandong University, 250100 Jinan, Shandong, People's Republic of China
| | - Yi Luo
- Department of Theoretical Chemistry, School of Biotechnology, Royal Institute of Technology, SE-10691 Stockholm, Sweden, Centre for Theoretical and Computational Chemistry, Department of Chemistry, University of Tromsφ, N-9037 Tromsφ, Norway, Istituto per i Processi Chimico-Fisici del Consiglio Nazionale delle Ricerche (IPCF-CNR), Area della Ricerca di Pisa, Via G. Moruzzi 1, I-56124 Pisa, Italy, and Institute of Crystal Materials, Shandong University, 250100 Jinan, Shandong, People's Republic of China
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26
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Shafirovich V, Dourandin A, Luneva NP, Singh C, Kirigin F, Geacintov NE. Multiphoton Near-Infrared Femtosecond Laser Pulse-Induced DNA Damage With and Without the Photosensitizer Proflavine. Photochem Photobiol 2008. [DOI: 10.1111/j.1751-1097.1999.tb03285.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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27
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Jones PB, Rozkalne A, Meyer-Luehmann M, Spires-Jones TL, Makarova A, Kumar ATN, Berezovska O, Bacskai BB, Hyman BT. Two postprocessing techniques for the elimination of background autofluorescence for fluorescence lifetime imaging microscopy. JOURNAL OF BIOMEDICAL OPTICS 2008; 13:014008. [PMID: 18315366 DOI: 10.1117/1.2837169] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
The analysis of fluorescence lifetime imaging microscopy (FLIM) data under complex biological conditions can be challenging. Particularly, the presence of short-lived autofluorescent aggregates can confound lifetime measurements in fluorescence energy transfer (FRET) experiments, where it can become confused with the signal from exogenous fluorophores. Here we report two techniques that can be used to discriminate the contribution of autofluorescence from exogenous fluorphores in FLIM. We apply the techniques to transgenic mice that natively express yellow fluorescence protein (YFP) in a subset of cortical neurons and to histological slices of aged human brain tissue, where we study the misfolding of intracellular tau protein in the form of neurofibrillary tangles.
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Affiliation(s)
- Phillip B Jones
- Harvard Medical School, Massachusetts General Hospital, MassGeneral Institute for Neurodegenerative Disorders, 114 16th Street, Charlestown, Massachusetts 02129, USA
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28
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Chang CC, Chu JF, Kao FJ, Chiu YC, Lou PJ, Chen HC, Chang TC. Verification of antiparallel G-quadruplex structure in human telomeres by using two-photon excitation fluorescence lifetime imaging microscopy of the 3,6-Bis(1-methyl-4-vinylpyridinium)carbazole diiodide molecule. Anal Chem 2007; 78:2810-5. [PMID: 16615797 DOI: 10.1021/ac052218f] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Different G-quadruplex structures for the human telomeric sequence d(T2AG3)4 in vitro have been documented in the presence of sodium and potassium. Verification of the G-quadruplex structures in human telomeres in vivo is the main issue in establishing the biological function of the G-quadruplex structures in telomeres as well as the development of anticancer agents. Here we have applied two-photon excitation fluorescence lifetime imaging microscopy to measure the fluorescence lifetime of the BMVC molecule upon interaction with various DNA structures. The distinction in lifetime measured with submicrometer spatial resolution in two-photon excitation fluorescence lifetime imaging microscopy provides a powerful approach not only to verify the existence of the antiparallel G-quadruplex structure in human telomeres but also to map its localizations in metaphase chromosomes.
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Affiliation(s)
- Cheng-Chung Chang
- Institute of Atomic and Molecular Sciences, Academia Sinica, P. O. Box 23-166, Taipei, 106, Taiwan, Republic of China
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29
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Davis SK, Bardeen CJ. Cross-linking of Histone Proteins to DNA by UV Illumination of Chromatin Stained with Hoechst 33342¶. Photochem Photobiol 2007. [DOI: 10.1562/0031-8655(2003)0770675rccohp2.0.co2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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30
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Cohanoschi I, Belfield KD, Toro C, Hernández FE. Solvent effects on the three-photon absorption cross-section of a highly conjugated fluorene derivative. J Chem Phys 2006; 125:161102. [PMID: 17092056 DOI: 10.1063/1.2370750] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Herein, we report the study of the three-photon absorption cross-section dependence on solvents parameters for a highly conjugated organic dye, 2,2'-(4,4'-(1E,1'E)-2,2'-(9,9-didecyl-9H-fluorene-2,7-diyl) bis(ethene-2,1-diyl)bis(4,1-phenylene))dibenzo[d]thiazole (A-pi-pi-pi-A). The three-photon absorption cross-section was measured for this organic dye in solution in four different solvents with polarity function, Deltaf between 0.162 and 0.247. The experiments show how the solvent's reorientation of the electrons and polarity contribute to the 3PA cross-section. Multiphoton-absorption experiments of A-pi-pi-pi-A in all four different solvents were performed with a tunable OPG pumped by a 25 picosecond Nd-YAG laser.
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Affiliation(s)
- Ion Cohanoschi
- Department of Chemistry and CREOL, College of Optics & Photonics, University of Central Florida, Orlando, Florida 32816-2366, USA
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31
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Denton ML, Schuster KJ, Rockwell BA. Accurate measure of laser irradiance threshold for near-infrared photo-oxidation with a modified confocal microscope. J Microsc 2006; 221:164-71. [PMID: 16551277 DOI: 10.1111/j.1365-2818.2006.01557.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Femtosecond mode-locked lasers are now being used routinely in multiphoton fluorescence and autofluorescence spectroscopy, are just beginning to be used in refractive surgery, and may be used in the future diagnosis of skin cancer. Pulses from these lasers induce non-linear effects in resultant tissue interactions. Using a modified confocal microscope with dispersion compensation and accurate measurements of beam diameter, a very low threshold was measured for photochemical oxidation in cultured cells. The measured threshold showed non-linear photo-oxidation at a peak irradiance and photon-flux density of 8.4x10(8) W cm-2 and 3.4x10(27) photons cm-2 s-1, respectively (90-fs pulse). The impact of these findings is significant to those using ultrashort lasers because they provide a tangible reference point (microscope-independent) for the generation of photo-oxidative stress in laser-exposed tissues, and because they highlight the importance of dispersion compensation in minimizing collateral tissue damage.
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Affiliation(s)
- Michael L Denton
- Northrop Grumman, Life Sciences Research and Applications, 4241 Woodcock Drive, Suite B-100, San Antonio, Texas 78228, USA.
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32
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Cohanoschi I, Belfield KD, Hernández FE. Three-photon absorption enhancement in symmetrical charge transfer pull–pull fluorene derivatives. Chem Phys Lett 2005. [DOI: 10.1016/j.cplett.2005.03.037] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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33
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Lukomska J, Gryczynski I, Malicka J, Makowiec S, Lakowicz JR, Gryczynski Z. Two-photon induced fluorescence of Cy5-DNA in buffer solution and on silver island films. Biochem Biophys Res Commun 2005; 328:78-84. [PMID: 15670753 PMCID: PMC6844251 DOI: 10.1016/j.bbrc.2004.12.148] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2004] [Indexed: 10/26/2022]
Abstract
We report the observation of a strong two-photon induced fluorescence emission of Cy5-DNA within the tunable range of a Ti:Sapphire laser. The estimated two-photon cross-section for Cy5-DNA of 400GM is about 3.5-fold higher than it was reported for rhodamine B. The fundamental anisotropies of Cy5-DNA are close to the theoretical limits of 2/5 and 4/7 for one- and two-photon excitation, respectively. We also observed an enhanced two-photon induced fluorescence (TPIF) of Cy5-DNA deposited on silver island films (SIFs). In the presence of SIFs, the TPIF is about 100-fold brighter. The brightness increase of Cy5-DNA TPIF near SIFs is mostly due to enhanced local field.
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Affiliation(s)
- Joanna Lukomska
- Center for Fluorescence Spectroscopy, Department of Biochemistry and Molecular Biology, University of Maryland at Baltimore, 725 West Lombard Street, Baltimore, MD 21201, USA.
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Hernández FE, Belfield KD, Cohanoschi I, Balu M, Schafer KJ. Three- and four-photon absorption of a multiphoton absorbing fluorescent probe. APPLIED OPTICS 2004; 43:5394-5398. [PMID: 15495431 DOI: 10.1364/ao.43.005394] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
High-order multiphoton excitation processes are becoming a reality for fluorescence imaging and phototherapy treatment because they afford minimization of scattered light losses and a reduction of unwanted linear absorption in the living organism transparency window, making them less susceptible to photodamage, while improving the irradiation penetration depth and spatial resolution. We report the four-photon-excited fluorescence emission of (7-benzothiazol-2-yl-9,-didecylfluoren-2-yl)diphenylamine in hexane and its four-photon absorption cross section sigma4' = 8.1 x 10(-109) cm8 s3 photon(-3) for the transition S0 --> S1 when excited at 1600 nm with a tunable optical parametric generator (OPG) pumped by picosecond laser pulses. When pumped at 1200 nm, three-photon absorption was observed, corresponding to the same transition.
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Affiliation(s)
- Florencio E Hernández
- Department of Chemistry and School of Optics/Center for Research and Education in Optics and Lasers/Florida Photonics Center of Excellence, University of Central Florida, Orlando, Florida 32816-2366, USA.
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35
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36
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Cannell MB, Jacobs MD, Donaldson PJ, Soeller C. Probing microscopic diffusion by 2-photon flash photolysis: measurement of isotropic and anisotropic diffusion in lens fiber cells. Microsc Res Tech 2004; 63:50-7. [PMID: 14677133 DOI: 10.1002/jemt.10422] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Two-photon excited flash photolysis (TPEFP) was used to photorelease caged fluorescein in test solutions and inside fiber cells of the eye lens. Accurate alignment between the focus of the IR beam and the probe beam from the confocal microscope was achieved with an accessory focussing lens and computer models of diffusion were fit to experimental data to extract apparent diffusion coefficients. Inside a fiber cell, the diffusion coefficient for fluorescein was 4 x 10(-7) cm(2)/s at 21 degrees C, a value an order of magnitude lower than observed in free solution. Fluorescence also diffused between fiber cells via gap junctions. In the periphery, diffusion between cells occurred mainly in a radial direction while deep in the lens the diffusion between cells appeared more isotropic. Diffusion between cells was slower than inside cells and corresponded to less than approximately 1% of the area between cells being available for diffusion. This value is in good agreement with that expected from measurements of gap junction structure and packing density if a 1-1.5-nm aqueous gap junction pore is nearly always open.
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Affiliation(s)
- M B Cannell
- Department of Physiology, School of Medicine and Health Sciences, University of Auckland, Auckland, New Zealand.
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37
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Zipfel WR, Williams RM, Webb WW. Nonlinear magic: multiphoton microscopy in the biosciences. Nat Biotechnol 2003; 21:1369-77. [PMID: 14595365 DOI: 10.1038/nbt899] [Citation(s) in RCA: 2205] [Impact Index Per Article: 105.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Multiphoton microscopy (MPM) has found a niche in the world of biological imaging as the best noninvasive means of fluorescence microscopy in tissue explants and living animals. Coupled with transgenic mouse models of disease and 'smart' genetically encoded fluorescent indicators, its use is now increasing exponentially. Properly applied, it is capable of measuring calcium transients 500 microm deep in a mouse brain, or quantifying blood flow by imaging shadows of blood cells as they race through capillaries. With the multitude of possibilities afforded by variations of nonlinear optics and localized photochemistry, it is possible to image collagen fibrils directly within tissue through nonlinear scattering, or release caged compounds in sub-femtoliter volumes.
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MESH Headings
- Biological Science Disciplines/instrumentation
- Biological Science Disciplines/methods
- Biological Science Disciplines/trends
- Equipment Design
- Image Enhancement/instrumentation
- Image Enhancement/methods
- Imaging, Three-Dimensional/instrumentation
- Imaging, Three-Dimensional/methods
- Imaging, Three-Dimensional/trends
- Microscopy, Confocal/instrumentation
- Microscopy, Confocal/methods
- Microscopy, Confocal/trends
- Microscopy, Fluorescence, Multiphoton/instrumentation
- Microscopy, Fluorescence, Multiphoton/methods
- Microscopy, Fluorescence, Multiphoton/trends
- Nonlinear Dynamics
- Transducers
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Affiliation(s)
- Warren R Zipfel
- School of Applied and Engineering Physics, 212 Clark Hall, Cornell University, Ithaca, New York 14853, USA
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38
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Davis SK, Bardeen CJ. Cross-linking of histone proteins to DNA by UV illumination of chromatin stained with Hoechst 33342. Photochem Photobiol 2003; 77:675-9. [PMID: 12870855 DOI: 10.1562/0031-8655(2003)077<0675:rccohp>2.0.co;2] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The photochemical effects of near-UV light on chromatin labeled with the vital DNA dye Hoechst 33342 (H33342) are studied. Several types of experiments demonstrate that illumination at both 365 and 410 nm results in significant cross-linking of proteins with the DNA. Fluorescence microscopy of dye-stained Xenopus XTC-2 nuclei shows that UV illumination has effects similar to chemical fixation by formaldehyde. At 365 nm a dose of approximately 70 J/cm2 results in 50% of the DNA being cross-linked, as measured by chloroform-sodium dodecyl sulfate extraction. At 410 nm the efficiency of cross-linking was smaller by a factor of 3. Gel electrophoresis of the cross-linked proteins shows them to be predominantly core histones. The implications of these results for experiments on live cells stained with H33342, for example, fluorescence microscopy of nuclear dynamics or cell sorting, are discussed.
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Affiliation(s)
- Sara K Davis
- Department of Chemistry, University of Illinois, Urbana, IL 61801, USA
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39
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Clegg RM, Holub O, Gohlke C. Fluorescence lifetime-resolved imaging: measuring lifetimes in an image. Methods Enzymol 2003; 360:509-42. [PMID: 12622166 DOI: 10.1016/s0076-6879(03)60126-6] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
We have given an overview of what one can gain by lifetime-resolved imaging and reviewed the major issues concerning lifetime-resolved measurements and FLI instrumentation. Instead of giving diverse selected examples, we have discussed the underlying basic pathways of deexcitation available to the molecules in the excited state. It is by traversing these pathways that compete kinetically with the fluorescence pathway of deactivation--and therefore affect the measured fluorescence lifetime--that we gain the information that lifetime-resolved fluorescence provides. It is hoped that being aware of the diversity, of pathways available to an excited fluorophore will facilitate potential users to recognize the value of FLI measurements and inspire innovative experiments using lifetime-resolved imaging. FLI gives us the ability within a fluorescence image of measuring and quantifying dynamic events taking place in the immediate surroundings of fluorophores as well as locating the fluorescent components within the image. Just as measurements in cuvettes, lifetime-resolved imaging extends considerably the potential information that can be derived from a fluorescence experiment. Our purpose has been to arouse an appreciation for the broad application of fluorescence lifetime-resolved measurements in imaging. We have given only general design characteristics of the instrumentation and discussed the characteristics that distinguish imaging from the single channel lifetime-resolved measurements. We have not provided details of the instrumentation or the presented many examples. These are available in the literature, and given in the references, and they are continually and rapidly growing.
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Affiliation(s)
- Robert M Clegg
- Department of Physics, University of Illinois Urbana-Champaign, Urbana 61801, USA
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40
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Gryczynski I, Piszczek G, Gryczynski Z, Lakowicz JR. Four-Photon Excitation of 2,2'-Dimethyl- p-terphenyl. J Phys Chem A 2002; 106:754-759. [PMID: 32009775 DOI: 10.1021/jp012860n] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We report the emission spectra, intensity decays, and anisotropy decay of 2,2'-dimethyl-p-terphenyl (DMT) with four-photon excitation. When excited with a fs Ti:Sapphire laser the emission intensity of DMT was found to depend on the third power of the incident intensity for excitation of 783 nm, and on the fourth power of the incident intensity for excitation at 882 nm. Surprisingly, at the highest value incident power, the emission intensity for four-photon excitation was about 10-fold less than with three-photon excitation. The emission spectra, intensity decays and correlation times were found to be identical for three- and four-photon excitation. However, the fundamental anisotropy (r 0) of DMT depended on the mode of excitation. To the best of our knowledge, the r 0 value of 0.70 is the highest ever observed for an isotropic solution. These results suggest that four-photon excitation can be used with red-NIR lasers to obtain excitation of UV-absorbing chromophores.
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Affiliation(s)
- Ignacy Gryczynski
- University of Maryland Baltimore, Center for Fluorescence Spectroscopy, Department of Biochemistry and Molecular Biology, 725 West Lombard Street, Baltimore, Maryland 21201
| | - Grzegorz Piszczek
- University of Maryland Baltimore, Center for Fluorescence Spectroscopy, Department of Biochemistry and Molecular Biology, 725 West Lombard Street, Baltimore, Maryland 21201
| | - Zygmunt Gryczynski
- University of Maryland Baltimore, Center for Fluorescence Spectroscopy, Department of Biochemistry and Molecular Biology, 725 West Lombard Street, Baltimore, Maryland 21201
| | - Joseph R Lakowicz
- University of Maryland Baltimore, Center for Fluorescence Spectroscopy, Department of Biochemistry and Molecular Biology, 725 West Lombard Street, Baltimore, Maryland 21201
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Plessow R, Brockhinke A, Eimer W, Kohse-Höinghaus K. Intrinsic Time- and Wavelength-Resolved Fluorescence of Oligonucleotides: A Systematic Investigation Using a Novel Picosecond Laser Approach. J Phys Chem B 2000. [DOI: 10.1021/jp994132u] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Regina Plessow
- Physikalische Chemie I, Fakultät für Chemie, Universität Bielefeld, Universitätsstr. 25, D-33615 Bielefeld, Germany
| | - Andreas Brockhinke
- Physikalische Chemie I, Fakultät für Chemie, Universität Bielefeld, Universitätsstr. 25, D-33615 Bielefeld, Germany
| | - Wolfgang Eimer
- Physikalische Chemie I, Fakultät für Chemie, Universität Bielefeld, Universitätsstr. 25, D-33615 Bielefeld, Germany
| | - Katharina Kohse-Höinghaus
- Physikalische Chemie I, Fakultät für Chemie, Universität Bielefeld, Universitätsstr. 25, D-33615 Bielefeld, Germany
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Malak H. Investigating up-conversion fluorescence of Phloxine B. IEEE ENGINEERING IN MEDICINE AND BIOLOGY MAGAZINE : THE QUARTERLY MAGAZINE OF THE ENGINEERING IN MEDICINE & BIOLOGY SOCIETY 1999; 18:37-40, 89-91. [PMID: 10497741 DOI: 10.1109/51.790990] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- H Malak
- Multi-Photon Time-Resolved Imaging Laboratory, Microcosm, Inc., Columbia, Maryland, USA.
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Abstract
We observed emission from the tyrosine derivative N-acetyl-L-tyrosinamide (NATyrA) when excited with the fundamental output of a femtosecond Ti:Sapphire laser from 780 to 855 nm. The dependence on incident laser power indicates a three-photon process. The emission spectra and intensity decay in glycerol-water (30:70) at 5 degrees C were found to be identical for one- and three-photon excitation. Also the excitation spectrum of three-photon-induced fluorescence of NATyrA corresponds to the one-photon excitation spectrum. The time-zero or fundamental anisotropy spectrum was reconstructed from the frequency-domain anisotropy decays. The three-photon anisotropies are similar or larger than the one-photon anisotropies. These three-photon anisotropies are surprising given the near zero values known for tyrosine with two-photon excitation. The observations indicate that one- and three-photon excitation directly populates the same singlet excited states(s). However, the origin of the anisotropies with multi-photon excitation of tyrosine remain unclear and unpredictable.
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Affiliation(s)
- I Gryczynski
- Department of Biochemistry and Molecular Biology, University of Maryland at Baltimore 21201, USA
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Lakowicz JR, Gryczynski I, Gryczynski Z. High Throughput Screening with Multiphoton Excitation. JOURNAL OF BIOMOLECULAR SCREENING 1999; 4:355-362. [PMID: 10838432 PMCID: PMC6986387 DOI: 10.1177/108705719900400610] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Fluorescence detection is extensively used in high throughput screening. In HTS there is a continuous migration toward higher density plates and smaller sample volumes. In the present report we describe the advantages of two-photon or multiphoton excitation for HTS. Multiphoton excitation (MPE) is the simultaneous absorption of two long-wavelength photons to excite the lowest singlet state of the fluorophore. MPE is typically accomplished with short but high-intensity laser pulses, which allows simultaneous absorption of two or more photons. The intensity of the multiphoton-induced fluorescence is proportional to the square, cube, or higher power of the instantneous photon flux. Consequently, two-photon or multiphoton excitation only occurs at the focal point of the incident beam. This property of two-photon excitation allows the excited volume to be very small and to be localized in the center of each well in the HTS plate. We show that two-photon-induced fluorescence of fluorescein can be reliably measured in microwell plates. We also show the use of 6-carboxy fluorescein as a pH probe with two-photon excitation, and measure 4'-6-diamidino-2-phenylindole (DAPI) binding and two-photon-induced fluorescence. In further studies we measure the time-dependent intensity decays of DAPI bound to DNA and of calcium-dependent fluorophores. Finally, we demonstrate the possibility of three-photon excitation of several fluorophores, including indole, in the HTS plate. These results suggest that MPE can be used in high-density multiwell plates.
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Affiliation(s)
- JR Lakowicz
- University of Maryland, School of Medicine, Baltimore, MD
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Lakowicz JR, Gryczynski I, Tolosa L, Dattelbaum JD, Castellano FN, Li L, Rao G. ADVANCES IN FLUORESCENCE SPECTROSCOPY: MULTI-PHOTON EXCITATION, ENGINEERED PROTEINS, MODULATION SENSING AND MICROSECOND RHENIUM METAL-LIGAND COMPLEXES. ACTA PHYSICA POLONICA: A 1999; 95:179-195. [PMID: 31660002 PMCID: PMC6816252 DOI: 10.12693/aphyspola.95.179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The technology and applications of fluorescence spectroscopy are rapidly advancing. In this overview presentation we summarize some recent developments from this laboratory. Two and three-photon excitation have been observed for a wide variety of intrinsic and extrinsic fluorophores, including tryptophan, tyrosine, DNA stains, membrane probes, and even alkanes. It has been possible to observe multi-photon excitation of biopolymers without obvious photochemical or photo-thermal effects. Although not de-scribed in our lecture, another area of increasing interest is the use of engineered proteins for chemical and clinical sensing. We show results for the glucose-galactose binding protein from E. coli. The labeled protein shows spectral changes in response to micromolar concentrations of glucose. This protein was used with a novel sensing method based on the modulated emission of the labeled proteins and a long lifetime reference fluorophore. And finally, we describe a recently developed rhenium complex which displays a lifetime near 3 µs in oxygenated aqueous solution. Such long life-time probes allow detection of microsecond dynamic processes, bypassing the usual nanosecond timescale limit of fluorescence. The result of these developments in protein engineering, sensing methods, and metal-ligand probe chemistry will be the increased use of fluorescence in clinical chemistry and point-of-care analyses.
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Affiliation(s)
- J R Lakowicz
- University of Maryland, School of Medicine, 725 West Lombard Street, Baltimore, Maryland 21201, USA
| | - I Gryczynski
- University of Maryland, School of Medicine, 725 West Lombard Street, Baltimore, Maryland 21201, USA
| | - L Tolosa
- University of Maryland, School of Medicine, 725 West Lombard Street, Baltimore, Maryland 21201, USA
| | - J D Dattelbaum
- University of Maryland, School of Medicine, 725 West Lombard Street, Baltimore, Maryland 21201, USA
| | - F N Castellano
- University of Maryland, School of Medicine, 725 West Lombard Street, Baltimore, Maryland 21201, USA
| | - L Li
- University of Maryland, School of Medicine, 725 West Lombard Street, Baltimore, Maryland 21201, USA
| | - G Rao
- Medical Biotechnology Center, Department of Chemical and Biochemical Engineering, 725 West Lombard Street, Baltimore, Maryland 21201, USA
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Gryczynski I, Gryczynski Z, Lakowicz JR. Fluorescence Anisotropy Controlled by Light Quenching. Photochem Photobiol 1998. [DOI: 10.1111/j.1751-1097.1998.tb09106.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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47
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Gryczynski I, Gryczynski Z, Lakowicz JR. Fluorescence Anisotropy Controlled by Light Quenching. Photochem Photobiol 1998. [DOI: 10.1111/j.1751-1097.1998.tb09467.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Castellano FN, Malak H, Gryczynski I, Lakowicz JR. Creation of Metal-to-Ligand Charge Transfer Excited States with Two-Photon Excitation. Inorg Chem 1997; 36:5548-5551. [PMID: 32223122 PMCID: PMC7075667 DOI: 10.1021/ic970334y] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We examined the steady state and time-resolved emission spectral properties of [Ru(bpy)3]2+ and [Ru(bpy)2-(dcb)]2+, where bpy is 2,2'-bipyridine and dcb is 2,2'-bipyridine-4,4'-dicarboxylic acid, in fluid solution when excited with 90 fs pulses from a mode-locked Ti/sapphire laser. Over the wavelength range 820-900 nm, both complexes displayed two-photon excitation as observed by a quadratic dependence of the emission intensity on incident power. Steady state emission and time-resolved frequency-domain intensity decay measurements revealed that two-photon excitation of each complex resulted in the same emission spectra and single-exponential decays as observed for one-photon excitation at a variety of temperatures in different solvents. The two-photon excitation cross section of [Ru(bpy)3]2+ measured at 880 nm was determined to be 4.3 × 10-50 cm4 s/photon. These results clearly show that metal-to-ligand charge transfer (MLCT) excited states can in fact be obtained through multiphoton processes.
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Affiliation(s)
- Felix N Castellano
- Department of Biochemistry and Molecular Biology, Center for Fluorescence Spectroscopy, University of Maryland School of Medicine, 725 West Lombard Street, Baltimore, Maryland 21201
| | - Henryk Malak
- Department of Biochemistry and Molecular Biology, Center for Fluorescence Spectroscopy, University of Maryland School of Medicine, 725 West Lombard Street, Baltimore, Maryland 21201
| | - Ignacy Gryczynski
- Department of Biochemistry and Molecular Biology, Center for Fluorescence Spectroscopy, University of Maryland School of Medicine, 725 West Lombard Street, Baltimore, Maryland 21201
| | - Joseph R Lakowicz
- Department of Biochemistry and Molecular Biology, Center for Fluorescence Spectroscopy, University of Maryland School of Medicine, 725 West Lombard Street, Baltimore, Maryland 21201
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Malak H, Castellano FN, Gryczynski I, Lakowicz JR. Two-photon excitation of ethidium bromide labeled DNA. Biophys Chem 1997; 67:35-41. [PMID: 9397517 DOI: 10.1016/s0301-4622(97)00017-3] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
We examined the steady state and time-resolved emission of DNA stained with ethidium bromide (EB) when excited with 90 fs pulses from a mode-locked titanium sapphire laser. Over the wavelength range from 840 to 880 nm EB-DNA was found to display two-photon excitation, with a cross-section near 7 x 10(-50) cm4s/photon. Frequency-domain intensity decay measurements revealed similar multi-exponential intensity decays for one- and two-photon excitation. Time-resolved anisotropy decay measurements revealed similar correlation times, but different amplitudes as has been observed previously for two- versus one-photon excitation. These results indicate that two-photon excitation of EB-DNA can be accomplished with the fundamental output of a Ti:sapphire laser without obvious heating or perturbation of the DNA.
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Affiliation(s)
- H Malak
- Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore 21201, USA
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