Sensitized absorption and emission of monomer and dimer forms of acridine orange adsorbed onto microcrystalline cellulose

Ultraviolet/Visible Absorption, Luminescence, and X-ray Photoelectron Spectroscopic Studies of a Rhodamine Dye Covalently Bound to Microcrystalline Cellulose

“…In the past decade we have made some surface photochemical studies of several dyes, including rhodamines, adsorbed onto a scarcely used adsorbent: powdered microcrystalline cellulose. − From these studies, a large amount of information concerning room-temperature fluorescence and phosphorescence, − triplet−triplet energy transfer, electron and hydrogen transfer, 1c,d,5a,b and the nature of the adsorption process 5c-e was obtained. All these processes are strongly dependent on the interaction of the probes with the matrix, which may provide a rigid environment strongly affecting the properties of the guest molecules.…”

Photophysical Studies of a New Water Soluble Indocarbocyanine Dye Adsorbed onto Microcrystalline Cellulose and beta-Cyclodextrin

“…10 −3 mbar) at 60 °C for at least 24 h before sample preparation. The samples were prepared using the solvent evaporation method [30,31,32,33,34,35,36,40]. This method consists of the addition of a solution containing the indocarbocyanine in dried ethanol to the previously dried microcrystalline cellulose, followed by slow solvent evaporation from the slurry under stirring in a fume cupboard.…”

“…1 cm quartz cells were used for measurement of powdered samples. The remission function, F(R), of a probe adsorbed or included onto a solid powdered adsorbent and calculated with the use of the Kubelka-Munk equation for optically thick samples (F(R) = (1−R) 2 /2R ), after correction for the blank, is proportional to the host concentration [30,31,32,33,34,35,36,40]. Solution measurements were made using the same apparatus in the normal transmission mode.…”

“…One of our group’s interests is the photophysical processes of several probes [30,31,32,33,34,35,36,37,38,39,40,41,42], including cyanine dyes [30,31,32,40,43] adsorbed on various heterogeneous powdered supports, particularly onto microcrystalline cellulose. Probes included within cyclodextrin [40,41] and calixarene [42] cavities were also investigated.…”

“…When a solution of the probe in one of these swelling solvents is added to microcrystalline cellulose, the cellulose to cellulose hydrogen bonds are replaced by cellulose to solvent bonds and the matrix swells to a degree which depends on the solvent used for sample preparation [34]. Probes can then penetrate into sub-microscopic pores of the solid substrate and stay strongly entrapped within the cellulose polymeric chains, after solvent removal [30,31,32,33,34,35,36,43]. …”