Optical brighteners, analysis Fluorescence

Fluorescence is much more widely used for analysis than phosphorescence. Yet, the use of fluorescent detectors is limited to the restricted set of additives with fluorescent properties. Fluorescence detection is highly recommended for food analysis (e.g. vitamins), bioscience applications, and environmental analysis. As to poly-mer/additive analysis fluorescence and phosphorescence analysis of UV absorbers, optical brighteners, phenolic and aromatic amine antioxidants are most recurrent [25] with an extensive listing for 29 UVAs and AOs in an organic solvent medium at r.t. and 77 K by Kirkbright et al. [149]. 

Fluorescence in UV radiation is a frequently used method for detection of TLC spots, e.g. of Tinuvin 326 [42]. The fluorescence emitted by optical brighteners under UV light on a thin-layer plate has been utilised as a means of analysing these compounds [42]. On the whole, the use of fluorescence detection in poly-mer/additive analysis of extracts is certainly not overwhelming. Applied fluorescence has been described in a monograph [156]. 

Fluorescence Photons (UV, visible or near-IR) Pigments, inks, optical brighteners, safety signs and clothing, analysis, biology, molecular electronics... 

Hesse and PfeifeU described the fluorescent detection of oil stains, the analysis of the distribution of optical brighteners in polyester/cotton blends and the... 

The unusually intense fluorescence of trithiophene derivatives has led to one patent on the use of such compounds as optical brighteners of fabrics 10). The lowest excited state of T1 and three derivatives must have n-n character, as their absorption maxima and fluorescence quantum yields are very similar in solvent systems of very different polarity (204). Oxygen does not quench the singlet excited state of T1 (209), which has a lifetime shorter than 1 x 10 s (104) and a quantum yield of fluorescence of ca. 0.06-0.08 (204,211). A more complete analysis of the fluorescence of T1 has been carried out in n-decane down to 4.2 K (27). 

Brightener, Optical n fluorescent dye, or pigment which absorbs UV radiation and re-emits light of a violet or bluish hue. Used to increase the luminance factor and to remove the yellowish of white or off-white materials. (Bart J (2005) Additives in polymers industrial analysis and applications. Wiley, New York). 

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