Dye sensors

Wolfbeis O.S., Fluorescence-based ion sensing using potential-sensitive dyes, Sensor ActuatB-Chem 1995 29 140. 

FOZAN (Fast OZone ANalyzer) is a chemioluminescence Ozone Analyser, based in the chemioluminescence reaction between ozone present in an air flow and a laser dyes sensor such as Rodamine B, Rodamine 6G and Kumarine 153. Range of concentration is (l-999)mgr/m3. 

We have found that different polymeric matrices provide diverse response patterns of polymer-incorporated CdSe nanocrystals to vapors of different polarity. Such work promises to complement existing solvatochromic organic dye sensors with more photostable and reliable sensor materials. The stability of the sensor response pattern from 2.8 and 5.6-nm nanocrystals in PMMA film over more than 10 h of continuous exposure of the film to laser radiation is very attractive for diverse applications where continuous monitoring is needed. 

Amao Y, Nakamura N (2004) Optical CO2 sensor with the combination of colorimetric change of a-naphtholphthalein and internal reference fluorescent porphyrin dye. Sensor Actual B 100 347-351... 

SENSORS WITH RESPONSE ON SOME XANTHENE DYES BASED ON MOLECULARLY IMPRINTED ELECTROSYNTHESIZED POLYMERS... 

NOVEL OPTICAL pH SENSORS BASED ON CATECHOL AZO DYE DERIVATIVES... 

In conclusion, synthetic dyes can be determined in solid foods and in nonalcoholic beverages and from their concentrated formulas by spectrometric methods or by several separation techniques such as TEC, HPLC, HPLC coupled with diode array or UV-Vis spectrometry, MECK, MEECK, voltammetry, and CE. ° Many analytical approaches have been used for simultaneous determinations of synthetic food additives thin layer chromatography, " " derivative spectrophotometry, adsorptive voltammetry, differential pulse polarography, and flow-through sensors for the specific determination of Sunset Yellow and its Sudan 1 subsidiary in food, " but they are generally suitable only for analyzing few-component mixtures. 

Valencia, M.C. et al., A flow-throngh sensor for the determination of the dye Sunset Yellow and its subsidiary Sudan 1 in foods. Quint. Anal., 19, 129, 2000. 

There is no doubt that metallic nanoparticles that have defined sizes and shapes will become key components of a number of novel, highly sophisticated products, the prototypes of which are currently emerging from the industrial R D departments. The outlook is promising for the industrial production of defined 1.4nm metal clusters for use as single electron switches or transistors, for the cost-effective fabrication of ultrapure metallic nanomaterials needed for dye solar cells or sensors, and for the reproducible production of (particularly) efficient and durable... 

Therefore, the application of sensors made it possible not only to detect and identify the molecules of singlet oxygen emitted during photosensibilization by dye molecules but to understand several peculiarities of redistribution of the energy of electron excitation and transfer to solids, as well. 

Anisotropy describes the rotational dynamics of reporter molecules or of any sensor segments to which the reporter is rigidly fixed. In the simplest case when both the rotation and the fluorescence decay can be represented by single-exponential functions, the range of variation of anisotropy (r) is determined by variation of the ratio of fluorescence lifetime (xF) and rotational correlation time ([Pg.9]

The switch between discrete emitter forms with fixed but different lifetimes corresponding to free (F) and bound (B) forms of the sensor. Belonging to the same dye, these two forms can be excited at the same wavelength. When excited, they emit light independently, and the observed nonexponential decay can be deconvolved into two different individual decays with lifetimes xF and x6 (Fig. 2b). The ratio of preexponential factors aF and aB will determine the target concentration [18] ... 

In intensity sensing, the most efficient and commonly used method of intrinsic referencing is the introduction of a reference dye into a sensor molecule (or into support layer, the same nanoparticle, etc.) so that it can be excited together with the reporter dye and provide the reference signal [1], The reference dye should conform to stringent requirements ... 

There are many possibilities to use these complex formations in fluorescence sensing. If the excimer is not formed, we observe emission of the monomer only, and upon its formation there appears characteristic emission of the excimer. We just need to make a sensor, in which its free and target-bound forms differ in the ability of reporter dye to form excimers and the fluorescence spectra will report on the sensing event. Since we will observe transition between two spectroscopic forms, the analyte binding will result in increase in intensity of one of the forms and decrease of the other form with the observation of isoemissive point [22]. 

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