Reevaluation of absolute luminescence quantum yields of standard solutions using a spectrometer with an integrating sphere and a back-thinned CCD detector

2009 ◽  
Vol 11 (42) ◽  
pp. 9850 ◽  
Author(s):  
Kengo Suzuki ◽  
Atsushi Kobayashi ◽  
Shigeo Kaneko ◽  
Kazuyuki Takehira ◽  
Toshitada Yoshihara ◽  
...  
Keyword(s):  
Quantum Yields ◽  
Integrating Sphere ◽  
Ccd Detector ◽  
Standard Solutions

Self-absorption correction for solid-state photoluminescence quantum yields obtained from integrating sphere measurements

2007 ◽  
Vol 78 (8) ◽  
pp. 086105 ◽  
Author(s):  
Tai-Sang Ahn ◽  
Rabih O. Al-Kaysi ◽  
Astrid M. Müller ◽  
Katherine M. Wentz ◽  
Christopher J. Bardeen
Keyword(s):  
Solid State ◽  
Quantum Yields ◽  
Integrating Sphere ◽  
Absorption Correction

Integrating Sphere Setup for the Traceable Measurement of Absolute Photoluminescence Quantum Yields in the Near Infrared

2012 ◽  
Vol 84 (3) ◽  
pp. 1345-1352 ◽  
Author(s):  
Christian Würth ◽  
Jutta Pauli ◽  
Cornelia Lochmann ◽  
Monika Spieles ◽  
Ute Resch-Genger
Keyword(s):  
Near Infrared ◽  
Quantum Yields ◽  
Integrating Sphere

Photochemical /Photocytotoxicity Studies of New Tetrapyrrolic Structures as Potential Candidates for Cancer Theranostics

2020 ◽  
Vol 17 (5) ◽  
pp. 661-669
Author(s):  
Luis F. Vieira Ferreira ◽  
Isabel Ferreira Machado ◽  
Ana Gama ◽  
Radu P. Socoteanu ◽  
Rica Boscencu ◽  
...  
Keyword(s):  
Photodynamic Therapy ◽  
Fluorescence Emission ◽  
Human Tumor ◽  
Phenyl Group ◽  
Quantum Yields ◽  
Integrating Sphere ◽  
Fluorescence Quantum Yields ◽  
Photodynamic Therapy Of Cancer ◽  
Cytotoxicity Studies ◽  
Absolute Measurements

Background: Detailed photochemical and photocytotoxicity studies of two new porphyrins: 5,10,15,20-meso-tetrakis-(4-acetoxy-3-methoxyphenyl) porphyrin (P2.1) and 5-(4-hydroxy-3- methoxyphenyl)-10,15,20-tris-(4-acetoxy-3-methoxyphenyl)porphyrin (P2.2) are reported, as potential candidates for theranostics. For powdered samples of P2.1 and P2.2 adsorbed onto a powdered biocompatible substrate, polyethylene glycol (PEG), a concentration study was performed, correlating the fluorescence emission intensity with sample absorption to determine the useful concentration range for photodynamic therapy of cancer (PDT) in which aggregation does not occur. Cytotoxicity studies were performed in dark and illuminated conditions. Methods: The laser induced luminescence set-up is home-made, a N2 laser is used as the excitation source and a time gated charged-coupled device (ICCD) as the detector. Fluorescence lifetime determinations were made using pulsed light sources from the excitation LEDs and measures of the fluorescence intensities at different time delays after the excitation pulse. The singlet oxygen formation quantum yields ΦΔ measurements were obtained by comparing the total area of the emission spectra for the reference compound and also for the samples under study in the same solvent and with the same optical density at the excitation wavelength (405 nm). An integrating sphere for relative and absolute measurements was used in this work as an alternative methodology to obtain the values for the fluorescence emission quantum yields (ΦF) of the adsorbed porphyrin under study. The cytotoxicity evaluation was made in the dark and under irradiation, using four different human tumor cell lines and one non-tumor primary cell culture. Results: In order to establish the useful range of concentrations of the sensitizer for PDT, and due to the use of powdered samples, a special methodology was needed: the variations of the fluorescence lifetimes and fluorescence quantum yields were evaluated as a function of the concentration of the dye, measured by (1-R)*fdye. Both ΦF and τF are constant in the range from 0.002 to about 0.050 μmol g-1, and only after that a concentration quenching effect becomes visible, decreasing both ΦF and τF. This methodology is based in the correlations established between the Remission Function values and ΦF and τF obtained for increasing values of the sensitizer concentrations. Conclusion: The study of the aggregation effects of P2.1 and P2.2 porphyrins into a PEG matrix allowed us to determine the usable concentration range for photodynamic therapy use, where the aggregation of porphyrins decreases, therefore reducing the PDT action. The use of an integrating sphere for relative and absolute measurements of fluorescence quantum yields and also the lifetime studies as a function of the dye loading confirms the useful range for the use of P2.1 and P2.2 in PEG as powdered samples. The determination of the GI50, the porphyrin concentration which inhibits 50% of the cell growth, evidences that P2.2, the A3B porphyrin overtakes P2.1 (the A4 porphyrin) in terms of PDT efficiency and both porphyrins are much better PDT agents than the unsubstituted porphyrin, TPP. These data clearly show that porphyrins P2.2 and P2.1 exhibit an excellent behaviour in terms of its photocytotoxicity. These results encourage us to pursuit in the study of this family of porphyrins in which a balance of hydrophobic versus hydrophilic substituents in the phenyl group was achieved.

Absolute Phosphorescence Quantum Yields of Singlet Molecular Oxygen in Solution Determined Using an Integrating Sphere Instrument

2015 ◽  
Vol 87 (4) ◽  
pp. 2360-2366 ◽  
Author(s):  
Naoya Hasebe ◽  
Kengo Suzuki ◽  
Hiroaki Horiuchi ◽  
Hiromi Suzuki ◽  
Toshitada Yoshihara ◽  
...  
Keyword(s):  
Molecular Oxygen ◽  
Quantum Yields ◽  
Integrating Sphere ◽  
Singlet Molecular Oxygen

Absolute Measurements of Photoluminescence Quantum Yields of Solutions Using an Integrating Sphere

2006 ◽  
Vol 16 (2) ◽  
pp. 267-273 ◽  
Author(s):  
Laurent Porrès ◽  
Adam Holland ◽  
Lars-Olof Pålsson ◽  
Andrew P. Monkman ◽  
Chris Kemp ◽  
...  
Keyword(s):  
Quantum Yields ◽  
Integrating Sphere ◽  
Absolute Measurements

Absolute Luminous Flux and Quantum Yield of Sm3+-Doped Cadmium-Aluminum-Silicate Glasses under the Pumping of Blue Light Emitting Diode

2013 ◽  
Vol 275-277 ◽  
pp. 1974-1977 ◽  
Author(s):  
Yu Lei ◽  
Fang Fang Fu ◽  
Li Zheng ◽  
Zhi Qiang Wang ◽  
Xin Zhao ◽  
...  
Keyword(s):  
Quantum Yield ◽  
Blue Light ◽  
Optical Radiation ◽  
Light Emitting Diode ◽  
Luminous Flux ◽  
Silicate Glasses ◽  
Integrating Sphere ◽  
Aluminum Silicate ◽  
Light Emitting ◽  
Ccd Detector

Absolute luminous flux and quantum yield for multichannel transition emissions have been determined in samarium ion (Sm3+)-doped cadmium-aluminum-silicate (CAS) glasses under the pumping of blue light emitting diode (LED) using an integrating sphere of 30 cm diameter, which connected to a CCD detector with a 400 μm-core optical fiber. The radiant flux and luminous flux for the visible transition emissions (550–750 nm) of Sm3+under the blue LED excitation were solved to be 123 μW and 32 mlm, respectively, which occupied 1.51% and 7.16% of the whole. The total quantum yield of the visible fluorescence of Sm3+has been calculated to be 2.52%. Investigation on optical radiation parameters for multichannel visible transition emissions of Sm3+in CAS glasses provides a reference in developing luminescence and display materials.

Evaluation of a Commercial Integrating Sphere Setup for the Determination of Absolute Photoluminescence Quantum Yields of Dilute Dye Solutions

2010 ◽  
Vol 64 (7) ◽  
pp. 733-741 ◽  
Author(s):  
Christian Würth ◽  
Cornelia Lochmann ◽  
Monika Spieles ◽  
Jutta Pauli ◽  
Katrin Hoffmann ◽  
...  
Keyword(s):  
Quantum Yields ◽  
Integrating Sphere ◽  
Dye Solutions
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