<title>Confocal spectral imaging by microspectrofluorometry using two-photon excitation: application to the study of anticancer drugs within single living cancer cells</title>

Ru(ii) PACT agents with a synchronous photo-catalyzed NADH depletion ability were reported for the first time and displayed good activity towards cisplatin-resistant cancer cells upon one- and two-photon excitation.

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Determination of two-photon excitation and emission spectra of fluorescent molecules in single living cells

10.1117/12.768306 ◽

2008 ◽

Cited By ~ 2

Author(s):

Valerică Raicu ◽

Anurag Chaturvedi ◽

Michael Stoneman ◽

Giorgi Petrov ◽

Russell Fung ◽

...

Keyword(s):

Emission Spectra ◽

Living Cells ◽

Two Photon ◽

Photon Excitation ◽

Single Living Cells ◽

Fluorescent Molecules ◽

Single Living ◽

Two Photon Excitation

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Tumour-targeting photosensitisers for one- and two-photon activated photodynamic therapy

Organic & Biomolecular Chemistry ◽

10.1039/c9ob00731h ◽

2019 ◽

Vol 17 (27) ◽

pp. 6585-6594 ◽

Cited By ~ 4

Author(s):

Sébastien Jenni ◽

Angélique Sour ◽

Frédéric Bolze ◽

Barbara Ventura ◽

Valérie Heitz

Keyword(s):

Photodynamic Therapy ◽

Cancer Cells ◽

Near Infrared ◽

Tumour Targeting ◽

Two Photon ◽

Photon Excitation ◽

Two Photon Excitation

Efficient receptor-mediated delivery of a folate-targeted photosensitiser to kill cancer cells following two-photon excitation in the near-infrared is demonstrated.

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Two-photon excitation microscopy in cellular biophysics

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100136684 ◽

1995 ◽

Vol 53 ◽

pp. 62-63

Author(s):

David W. Piston ◽

Brian D. Bennett ◽

Robert G. Summers

Keyword(s):

Confocal Microscopy ◽

Laser Beam ◽

Duty Cycle ◽

Excited Electronic State ◽

Input Power ◽

Two Photon ◽

Simultaneous Absorption ◽

Photon Excitation ◽

Very High ◽

Two Photon Excitation

Two-photon excitation microscopy (TPEM) provides attractive advantages over confocal microscopy for three-dimensionally resolved fluorescence imaging and photochemistry. Two-photon excitation arises from the simultaneous absorption of two photons in a single quantitized event whose probability is proportional to the square of the instantaneous intensity. For example, two red photons can cause the transition to an excited electronic state normally reached by absorption in the ultraviolet. In practice, two-photon excitation is made possible by the very high local instantaneous intensity provided by a combination of diffraction-limited focusing of a single laser beam in the microscope and the temporal concentration of 100 femtosecond pulses generated by a mode-locked laser. Resultant peak excitation intensities are 106 times greater than the CW intensities used in confocal microscopy, but the pulse duty cycle of 10-5 maintains the average input power on the order of 10 mW, only slightly greater than the power normally used in confocal microscopy.

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Two-photon excitation fluorescence microscopy in living systems

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100146618 ◽

1993 ◽

Vol 51 ◽

pp. 154-155 ◽

Cited By ~ 1

Author(s):

David W. Piston

Keyword(s):

Confocal Microscopy ◽

Fluorescence Microscopy ◽

Singlet State ◽

Excited Electronic State ◽

Input Power ◽

Two Photon ◽

Simultaneous Absorption ◽

Photon Excitation ◽

Very High ◽

Two Photon Excitation

Two-photon excitation fluorescence microscopy provides attractive advantages over confocal microscopy for three-dimensionally resolved fluorescence imaging. Two-photon excitation arises from the simultaneous absorption of two photons in a single quantitized event whose probability is proportional to the square of the instantaneous intensity. For example, two red photons can cause the transition to an excited electronic state normally reached by absorption in the ultraviolet. In our fluorescence experiments, the final excited state is the same singlet state that is populated during a conventional fluorescence experiment. Thus, the fluorophore exhibits the same emission properties (e.g. wavelength shifts, environmental sensitivity) used in typical biological microscopy studies. In practice, two-photon excitation is made possible by the very high local instantaneous intensity provided by a combination of diffraction-limited focusing of a single laser beam in the microscope and the temporal concentration of 100 femtosecond pulses generated by a mode-locked laser. Resultant peak excitation intensities are 106 times greater than the CW intensities used in confocal microscopy, but the pulse duty cycle of 10−5 maintains the average input power on the order of 10 mW, only slightly greater than the power normally used in confocal microscopy.

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Two‐photon excitation fluorescence microscopy using a semiconductor laser

Bioimaging ◽

10.1002/1361-6374(199506)3:2<70::aid-bio3>3.3.co;2-n ◽

1995 ◽

Vol 3 (2) ◽

pp. 70-75 ◽

Cited By ~ 15

Author(s):

Pekka E Hänninen ◽

Martin Schrader ◽

Erkki Soini ◽

Stefan W Hell

Keyword(s):

Fluorescence Microscopy ◽

Semiconductor Laser ◽

Two Photon ◽

Photon Excitation ◽

Two Photon Excitation

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Two-Photon Excitation Imaging of Glucose Metabolism in Living Tissue

Microscopy and Microanalysis ◽

10.1017/s1431927600008412 ◽

1997 ◽

Vol 3 (S2) ◽

pp. 305-306

Author(s):

David W. Piston

Keyword(s):

Confocal Microscopy ◽

Collection Efficiency ◽

Three Dimensional ◽

Spatial Filter ◽

Input Power ◽

Photon Absorption ◽

Focal Volume ◽

Two Photon ◽

Photon Excitation ◽

Two Photon Excitation

Two-photon excitation microscopy (TPEM) provides attractive advantages over confocal microscopy for three-dimensionally resolved fluorescence imaging and photochemistry. It provides three-dimensional resolution and eliminates background equivalent to an ideal confocal microscope without requiring a confocal spatial filter, whose absence enhances fluorescence collection efficiency. This results in inherent submicron optical sectioning by excitation alone. In practice, TPEM is made possible by the very high local instantaneous intensity provided by a combination of diffraction-limited focusing of a single laser beam in the microscope and the temporal concentration of 100 femtosecond pulses generated by a mode-locked laser. Resultant peak excitation intensities are 106 times greater than the CW intensities used in confocal microscopy, but the pulse duty cycle of 10−5 limits the average input power to less than 10 mW, only slightly greater than the power normally used in confocal microscopy. Because of the intensity-squared dependence of the two-photon absorption, the excitation is limited to the focal volume.

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