Rhodamine activity

Organic Dye Lasers. Organic dye lasers represent the only weU-developed laser type in which the active medium is a Hquid (39,40). The laser materials are dyestuffs, of which a common example is rhodamine 6G [989-38-8]. The dye is dissolved in very low concentration in a solvent such as methyl alcohol [67-56-17, CH OH. Only small amounts of dye are needed to produce a considerable effect on the optical properties of the solution. 

Total pectinase, cellulase and lipase activities secreted by colonies were detected on BSM plates containing respectively 1% of citrus pectin, 2% Walseth cellulose and 1% olive oil + rhodamine. After few days at 30°C, pectin plates were covered by 1% CTAB for Ihour, positive colonies became surrounded by a clear halo walseth plates are not stained the halo is visible directly on positive clones lipase activity is revealed under UV on oil-rhodamine plates. 

We also tried measurements to demonstrate that hot spots make significant contributions to surface enhanced Raman scattering [34]. For this purpose, the sample of nanoparticie assembly was doped with Raman active molecules by a spincoating method, and near-field excited Raman scattering from the sample was recorded. We adopted Rhodamine 6G dye as a Raman active material, which is... 

N-doped titania demonstrated promising activity under visible light for the degradation of Rhodamine B in aqueous solutions [85], In thin-films of N-doped Ti02, the formation of nitride phases enhanced the catalytic properties of the film [86]. 

Guzikowski AP, Naleway JJ, Shipp CT, Schutte RC (2000) Synthesis of a macrocyclic rhodamine 110 enzyme substrate as an intracellular probe for caspase 3 activity. Tetrahedron Lett 41 4733 1735... 

Nestmann ER, Douglas GR, Matula TI, Grant CE, Kowbel DJ (1979) Mutagenic activity of rhodamine dyes and their impurities as detected by mutation induction in Salmonella and DNA damage in Chinese hamster ovary cells. Cancer Res 39 4412-4417... 

Activity-based protein profiling (ABPP) is a chemical proteomic strategy in which active-site-directed covalent probes are used to profile the functional states of enzymes in complex proteomes. Activity-based probes (ABPs) can distinguish active enzymes from their inactive zymogens or inhibitor-bound forms. They contain a reactive group intended to modify enzyme active sites covalently and a reporter group (typically rhodamine or biotin) that assists in detection and identification of protein targets. 

A different strategy for measuring protease activity is based on the property of xanthene dyes to form H-type dimers (see Sect. 6.2.3) when they are in close proximity. These dimers are accompanied with a characteristic quenching of their fluorescence and, particularly for rhodamines, with a blue shift in the absorption spectrum [121, 122]. The probe D-NorFES-D designed to measure activity of elastase in HL-60 cells consists of an undecapeptide derivatized with one tetramethylrhodamine dye on each side. The sequence contains proline residues to create a bent structure and bring the two fluoro-phores in close proximity. Intact D-NorFES-D shows 90% of its fluorescence quenched plus a blue shift of the absorption spectrum. After addition of the serine protease elastase, an increase in the fluorescence and a bathochromic shift of the absorption spectrum is observed, resulting in an increase in the emission ratio [80],... 

In this case, a loss of FRET is observed when the transferable lipid moves to an acceptor membrane. The most common FRET pair used for these studies is the NBD/rhodamine pair [160, 161], Some other FRET pairs have been used for the study of membrane sideness conservation [162] and intermembrane lipid transfer [163], Distinguishably, a study of membrane activation by molecular selective recognition was performed using FRET [97],... 

We then used this Caco-2 cell assay to categorize representative fluoroquinolone drug substance permeability [50], The drugs demonstrated some concentration-dependent permeability indicative of active drug transport. Based upon comparison to labetalol, ciprofloxacin was classified as a LP drug, whereas levofloxacin, lomefloxacin, and ofloxacin were classified as HP drugs, which matched their human in vivo bioavailabilities. All four fluoroquinolone drugs were subject to efflux transport (ciprofloxacin > lomefloxacin > rhodamine 123 > levofloxacin > ofloxacin). 

Kim M, Cooper DD, Hayes SF, Spangrude GJ. Rhodamine-123 staining in hematopoietic stem cells of young mice indicates mitochondrial activation rather than dye efflux. Blood. 1998 91 4106-4117. 

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