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Chloride detection with two fluorophores for robustness
Published in Airong Chen, Xin Ruan, Dan M. Frangopol, Life-Cycle Civil Engineering: Innovation, Theory and Practice, 2021
M. Dhouib, T. Sanchez, D. Conciatori, J. Asselin
In aqueous solution, the normalized fluorescence intensity recorded shows that the spectral distribution of Lucigenin has maximum excitations at 340, 385 and 450 nm; and a maximum emission at λEmLc=507 nm. The Rhodamine B has a maximum excitation at 546 nm and a maximum emission at λEmRhB=566 nm. The reference dye emitted at a significantly different wavelength from the indicator dye which makes the separation between the two signals possible. The emission spectra of Lc and the reference RhB must be different to distinguish the emission peaks and fractional intensity of the two fluorophores. Moreover, both dyes have an overall maximum excitation wavelength beyond 405 nm which makes them excitable by a blue LED system.
Biosorption and Discolorization of Textile Dye Effluent Using Fungi Isolated From Soil Samples Collected Near Textile Dye Industry
Published in Bakrudeen Ali Ahmed Abdul, Microbial Biofilms, 2020
Rhodamine-B (bright reddish-white powder) is a synthetic red to pink colored water and alcohol-soluble dye having brilliant fluorescent qualities with molecular formula C29H29N2O5ClNa2. Rhodamine-B is a fluorescent cationic dye in which the dye type becomes more important in textile dyeing because of its more rigid structure than other organic dyes. Due to its cationic structure, it can be applied to anionic fabrics which contain negative charges such as polyester fibers, wool, silk, and acrylic fibers. The dye is brilliant and the most fluorescent among other synthetic dyes. Rhodamine is often used as a tracer dye within water to determine the rate and direction of flow and transport. Rhodamine-B basic dye has wide applications in the dyeing of cotton, silk, paper, bamboo, weed, straw, and leather. Apart from this, it is widely employed in the preparation of carbon paper, ball-point pen, stamp pad inks, paint, and printing ink manufacturing. Rhodamine-B dye was the IARC monographs on the evaluation of carcinogenic risk of chemicals to humans.
A contribution to toxicity of fluorescent tracers
Published in A. Kranjc, Tracer Hydrology 97, 2020
Different fluorescent tracers have been investigated with in-vivo tests with mammals by several researchers. The LD50 of the most applied tracers are presented in Table 2 for different animals. It seems that these dyes are only toxic in very high doses, which far exceed those used in hydrological tracing. Consideration of further studies concerning human toxicological tests supports, in principle, the latest results obtained. A brief summary is given in the following. Uranine is considered harmless (Käss 1967). Many researchers have investigated the toxicity of the rhodamine family, e.g Nestmann & Kowbel (1979), Smart (1982), Behrens (1991) and Hofstraat et al. (1991). It appears that the rhodamine group as a whole is suspected to be toxic. Rhodamine WT is usually considered less toxic than RB. Rhodamine B is generally the most toxic of the tracers investigated, and proved to be a mutagen/carcinogen, its commercial sources contain mutagenic impurities. Rhodamine WT might be mutagenic. It was assumed that SRB and ARG, are also mutagens, however, Table 1 indicates that these dyes showed negative results in the two in-vitro mutagenicity tests.
Carbon-covered mesoporous silica and its application in Rhodamine B adsorption
Published in Environmental Technology, 2018
R. C. S. Nascimento, A. O. S. Silva, L. Meili
This work aims to evaluate the adsorption efficiency of MCM-41 and SBA-15 and of the corresponding materials modified by carbon deposition, MCM-41 CC and SBA-15 CC, with respect to removal of Rhodamine B from aqueous solution. Rhodamine B has been used as analytical reagent to detect metals and for dyeing cotton, silk, paper, bamboo, and leather. It is not strongly hazardous; however, it could cause toxic effects in the skin, eyes and respiratory, and gastrointestinal tracts. Besides, when released into water, dyes could make it difficult for the light penetration and the oxygen consumption, affecting the aquatic life negatively [16–20]. Sucrose was used as the carbon source because of its non-toxicity, biodegradability and because this raw material can be obtained from a renewable and low-cost source [21,22].
Microwave and combustion methods: a comparative study of synthesis, characterization, and applications of NiO nanoparticles
Published in Inorganic and Nano-Metal Chemistry, 2023
S. Pramila, V. Lakshmi Ranganatha, G. Nagaraju, C. Mallikarjunaswamy
Rhodamine B dye absorbs at 554 nm. The decrease in absorbance concerning irradiation time indicates the degradation of RhB as well as degradation of the aromatic part. Below graphical representation of NiCM1, NiCM2, and NiCM3 show the degradation efficiencies of 87.738%, 83.634%, and 80.739%, respectively. Microwave synthesized NiMW1, NiMW2, NiMW3 show the degradation efficiencies of 83.61%, 89.42%, 85.1%, respectively. Among combustion synthesized nanoparticles NiCM1 exhibits the highest degradation efficiency. Whereas in microwave synthesized nanoparticles NiMW2 shows the highest degradation efficiency over RhB dye after the irradiation of visible light. Hence, it was confirmed that NiMW2 exhibits more degradation efficiency compare to other NiO nanoparticles.
Stable and bioactive W/O/W emulsion loaded with “Pitanga” (Eugenia uniflora L.) leaf hydroethanolic extract
Published in Journal of Dispersion Science and Technology, 2022
Larissa Tessaro, Carla Giovana Luciano, Maria Fernanda Libório Martins, Ana Paula Ramos, Milena Martelli-Tosi, Paulo José do Amaral Sobral
The morphology of the droplets of the W/O/W emulsion with the more stable formulation was analyzed using a confocal laser scanning microscope (SP5, Leica Microsystems GmbH, Berlin, Germany) with an objective of 63x (1.4 aperture and oil immersion). The W/O/W emulsion was prepared with rhodamine B solution (0.1% m/v) added in the PLHE phase and fast green solutions (0.1% v/v) added in the external aqueous phase in order to stain protein. Rhodamine B was excited with HeNe laser at 543 nm; the emitted light was recorded between 570 to 640 nm. Fast green was excited with laser at 633 nm, and the emitted light was recorded at between 655 to 755 nm. These analyses were made in the Multiuser Laboratory of Confocal Microscopy of the FMRP-USP.