Fluorescence hydroperoxide group

Photothermal dehydrochlorination of PVC as studied by derivative ultraviolet absorption and fluorescence analysis techniques has shown that carbonyl and hydroperoxide groups are more important in the initiation steps than... 

Formation of hydroperoxide groups causes quenching of the fluorescence emission from excited phenyl groups in rubbers containing phenyl groups... 

Fig. 2.4. Schematic plot of fluorescence intensity (If) and concentration of hydroperoxide groups (OOH) versus energy absorbed for (a) EDPM rubber and (b) styrene-butadiene rubber (SBR). (Reprinted with permission from [293], Pergamon Press Ltd, Oxford, England.)...

Browning Reactions. The fluorescent components formed in the browning reaction (8) of peroxidized phosphatidylethanolamine are produced mainly by interaction of the amine group of PE and saturated aldehydes produced through the decomposition of fatty acid hydroperoxides. 

Chemical ionization mass spectrometric detection has been explored for the detection of methyl hydroperoxides However, fluorometry has dominated the current detection schemes for the organic peroxides. Typically, a nonfluorescent substrate is oxidized by the peroxide to generate a fluorescent product. These methods are sufficiently sensitive for accurate measurement of the peroxides in the low ppt by volume. For example, the peroxidase-catalyzed dimerization of p-hydroxyphenylacetic acid (POPHA) occurs in the presence of a peroxy group at elevated pH. The formation of the fluorescent dimer, detected by excitation at 310 nm and emission at 405 nm, is proportional to the concentration of the peroxide. The most common peroxidase catalyst used for this reaction is horseradish peroxidase (HRP). Cost and stability issues with the use of HRP led to the use of other catalysts, such as metalloporphyrins or phthalocyanine complexes. Another fluorescent reaction scheme involves the oxidation of the nonfluorescent thiamine (vitamin Bi) to the fluorescent thiochrome by the peroxide group. This reaction is catalyzed by bovine hematin. This reaction is 25-fold more sensitive for H2O2 than for the organic peroxides. 

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