Rhodamine solution preparation

Filter standards used for calibration and method assessment were prepared by adding 2 pL drops of standard solutions with concentration of 0-100 mg L onto blank filters. The solutions were prepared in 100 mL acid washed flasks by dilution of a multi-element standard (Merck CertiPUR, 1,000 mg L ) in 18 MQ cm water obtain from a Milli-Q Gradient system (Milhpore, Bedford, MA) with 7 mL eoneentrated nitric acid (65% HNO3, suprapure grade) and 2 mL of a Rhodamine B dye solution (prepared by dissolution of 0.125 g Rhodamine B... 

Fig. 40. Variation of the fluorescence intensity of rhodamine B and rhodamine B isothiocyanate adsorbed onto microcrystalline cellulose measured as the total area under the corrected emission spectrum,, as a function of (1 — 7 )/dye. Curve (1)—Type I samples of rhodamine B prepared from ethanolic solutions. Curve (2)—Type I samples of the reactive dye prepared from ethanol. Curve (3)—Type I samples of the reactive dye prepared from water. Curve (4)—Type II or dyed samples. Samples from curves 3 and 4 were repeatedly washed after the initial solvent evaporation.

For microinjections, we dope the injection solution with rhodamine dextran, which we have found to be nontoxic and without effect on subsequent development when injected with control solutions. Prepare a 20 J.g/fil stock solution of tetramethylrhodamine dextran, 70,000 molecular weight (Molecular Probes D-1819), sterilize by filtration, and store at -20°C. Dilute the stock in injection solution to a final concentration of 1 p,g/ J.l. 

Bromophenol blue 2, 7 -DichIorofluorescein Eosin, tetrabromofluorescein Fluorescein Potassium rhodizonate, C404(0K)2 Rhodamine 6G Sodium 3-aIizarinsuIfonate Thorin Dissolve 0.1 g of the acid in 200 mL 95% ethanol. Dissolve 0.1 g of the acid in 100 mL 70% ethanol. Use 1 mL for 100 mL of initial solution. See Dichlorofluorescein. Dissolve 0.4 g of the acid in 200 mL 70% ethanol. Use 10 drops. Prepare fresh as required by dissolving 15 mg in 5 mL of water. Use 10 drops for each titration. Dissolve 0.1 g in 200 mL 70% ethanol. Prepare a 0.2% aqueous solution. Use 5 drops per 120 mL endpoint volume. Prepare a 0.025% aqueous solution. Use 5 drops. 

NHS-rhodamine is insoluble directly in aqueous solution and should be dissolved in organic solvent prior to addition of a small aliquot to a buffered reaction medium. Concentrated stock solutions may be prepared in DMSO or DMF. Such solutions are relatively stable for short... 

In the case of /3-diketones which are not too sterically demanding, the [M(j8-diketonate)4] anion may be obtained. An example is NH4[M(CF3COCHCOCF3)4], where M = Y, Nd, Gd or Er. Preparation is by treatment of a benzene solution of [M(CF3COCHCOCF3)3] with CF3COCH2COCF3 (lmol) and gaseous ammonia.294 The (rhodamine 6G)+ salts of [E11L4]-, where L is benzoylacetonate or thenoyltrifluoroacetonate, have also been prepared and their fluorescence spectra studied.295... 

The reagent is prepared by dissolving 0-01 g of rhodamine-B in 100 ml of water. A more concentrated reagent is obtained by dissolving 0-05 g of rhodamine-B in a 15 per cent solution of potassium chloride in 2m hydrochloric acid. 

Rhodamine-B (0 01%). Dissolve 0-01 g rhodamine-B, C28H31N203CL (Colour Index 45170), in 100 ml water. For the preparation of a more concentrated solution see Section m.15, reaction 7. ... 

The standard solutions of three organic dyes, rhodamine B, fluorescein, eosin Y and their mixtures were prepared with 2.5xl0 mol/l NaOH. The two-way EM/EX matrices of size... 

Arabidopsis thaliana seedlings were grown using a 1 x 10-4 M Rhodamine-6G aqueous solution on a filter paper of glass fiber. For the preparation of microscopic specimens, Arabidopsis thaliana roots were crushed between two glass slides after soaking in 1M HC1 in a hot-water bath for 10 min, and washed with 45% acetic add and 3 1 methanol/acetic acid. The preparation was sealed in nujol mull with a cover slip. 

Other experimental techniques have been used to study the very fast relaxation of dye molecules in solution. Ricard and Ducuing studied rhodamine molecules in various solvents and observed vibrational rates ranging from 1 to 4 ps for the first excited singlet state. Their experiment consisted of two pulses with a variable delay time between them the first excites molecules into the excited state manifold and the second measures the time evolution of stimulated emission for different wavelengths. Ricard found a correlation between fast internal conversion and vibrational relaxation rates. Laubereau et al. found a relaxation time of 1.3 0.3 ps for coumarin 6 in CCI4. They used an infrared pulse to prepare a well-defined vibrational mode in the ground electronic state, and monitored the population evolution with a second pulse that excited the system to the lowest singlet excited state, followed by fluorescence detection. 

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