Rose bengal immobilization

Among the more interesting applications of polymer Rose Bengal is that of a sensitizer in studying the oxidation of other polymeric substrates [301]. Rose Bengal immobilized on Sepharose has been reported as a sensitizer for protein photooxidation [302], The oxygen uptake by the amino acids cysteine, hisitidine, methionine, tryptophan, and tyrosine was reported to be about 20% as much from the immobilized dye as from the free dye in aqueous solution. 

Silica gel as a support for Rose Bengal was reported by Tamagaki, Liesner, and Neckers [303], A similar system had been reported previously with the sensitizer methylene blue [304], Rose Bengal immobilized to poly(2-hydroxyethyl methacrylate) has also been reported by Schaap [305],... 

Recent experiments with pea chloroplasts illuminated in the absence of an electron acceptor have shown that both chlorophyll and linolenic acid breakdown was retarded by the singlet quenchers DABCO and crocin (23), Further work showed that linolenic acid breakdown and ethane generation in isolated chloroplast thylakoids was promoted by the addition of the singlet oxygen generator rose bengal immobilized on DEAE-sepharose (24). 

Rose bengal immobilized to polystyrene beads is not bleached. Rose bengal in solution bleaches with continued radiation. 

Self quenching of excited state dye by ground state dye with rose bengals immobilized to soluble polystyrenes occurs, but it is not observed with the beads. 

Fig. 21 Phosphorescence spectra of Rose Bengal immobilized on an organic glass with and without SIFs at 77 K (lexc = 532 nm). (Reprinted with permission from [129]. Copyright 2006 American Chemical Society)...

Rose Bengal has been immobilized on a number of other supports. In the original patent (Neckers, Blossey, and Schaap) a number of these are listed. 

The immobilization of rose bengal to non-crosslinked poly(styrene-co-chloromethyIstyrene) is shown for a 3 1 co-polymer with differing concentration of rose bengal in Table HI. 

Polymer rose bengal beads are most easily analyzed by fluorescence excitation spectroscopy. The emission spectra of immobilized dyes are presented as a function of solvent, of C-6 counter ion and dye-dye aggregation in this review. 

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