Biomaterial Database

Validation of fluorescence quantum yields for light-scattering powdered samples by laser-induced optoacoustic spectroscopy. 2009

Eugenia P Tomasini, and Enrique San Román, and Silvia E Braslavsky

INQUIMAE/DQIAyQF, Facultad de Ciencias Exactas y Naturales, UBA, Ciudad Universitaria, Pab. II, C1428EHA Buenos Aires, Argentina.

Determination of quantum yields for various processes (such as fluorescence and triplet formation) in dye-loaded light-scattering powdered samples is an open issue. Here, we report the testing of laser-induced optoacoustic spectroscopy (LIOAS) for the determination of fluorescence quantum yields of Rhodamine 101 and Rhodamine 6G adsorbed at various loadings on microgranular cellulose powder. The results of the LIOAS experiments are consistent with those from the method developed in one of our laboratories based on the measurement of apparent reflectance using an integrating sphere [Mirenda, M.; Lagorio, M. G.; San Roman, E. Langmuir 2004, 20, 3690-3697], which allows the simultaneous calculation of fluorescence quantum yield and reflectance devoid of fluorescence artifacts. Criteria to quantify overall errors and detect outlying values are developed. The theory underlying the application of LIOAS to light-scattering samples and experimental details are presented.

UI	MeSH Term	Description	Entries
D007834	Lasers	An optical source that emits photons in a coherent beam. Light Amplification by Stimulated Emission of Radiation (LASER) is brought about using devices that transform light of varying frequencies into a single intense, nearly nondivergent beam of monochromatic radiation. Lasers operate in the infrared, visible, ultraviolet, or X-ray regions of the spectrum.	Masers,Continuous Wave Lasers,Pulsed Lasers,Q-Switched Lasers,Continuous Wave Laser,Laser,Laser, Continuous Wave,Laser, Pulsed,Laser, Q-Switched,Lasers, Continuous Wave,Lasers, Pulsed,Lasers, Q-Switched,Maser,Pulsed Laser,Q Switched Lasers,Q-Switched Laser
D011208	Powders	Substances made up of an aggregation of small particles, as that obtained by grinding or trituration of a solid drug. In pharmacy it is a form in which substances are administered. (From Dorland, 28th ed)	Powder
D002482	Cellulose	A polysaccharide with glucose units linked as in CELLOBIOSE. It is the chief constituent of plant fibers, cotton being the purest natural form of the substance. As a raw material, it forms the basis for many derivatives used in chromatography, ion exchange materials, explosives manufacturing, and pharmaceutical preparations.	Alphacel,Avicel,Heweten,Polyanhydroglucuronic Acid,Rayophane,Sulfite Cellulose,alpha-Cellulose,Acid, Polyanhydroglucuronic,alpha Cellulose
D005453	Fluorescence	The property of emitting radiation while being irradiated. The radiation emitted is usually of longer wavelength than that incident or absorbed, e.g., a substance can be irradiated with invisible radiation and emit visible light. X-ray fluorescence is used in diagnosis.
D012235	Rhodamines	A family of 3,6-di(substituted-amino)-9-benzoate derivatives of xanthene that are used as dyes and as indicators for various metals; also used as fluorescent tracers in histochemistry.	Rhodamine
D013057	Spectrum Analysis	The measurement of the amplitude of the components of a complex waveform throughout the frequency range of the waveform. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)	Spectroscopy,Analysis, Spectrum,Spectrometry