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Monodisperse crosslinked core–shell micrometer‐sized microspheres bearing a brightly blue fluorescent dye, carbazole, and containing various functional groups in the shell layers were prepared by a two‐stage distillation–precipitation polymerization in acetonitrile in the absence of any stabilizer. Commercial divinylbenzene (DVB), containing 80 vol.% of DVB, was polymerized by distillation–precipitation in acetonitrile without any stabilizer using 2,2′‐azobisisobutyronitrile (AIBN) as the initiator for the first stage of polymerization which resulted in monodisperse polyDVB microspheres used as the core. Several functional monomers, including 2‐hydroxyethyl methacrylate and acrylonitrile together with N‐vinylcarbazole blue fluorescent comonomer, were incorporated into the shell layers with AIBN as initiator during the second stage of polymerization. The resultant core–shell polymer microspheres were characterized using scanning electron microscopy, Fourier transform infrared spectroscopy, UV‐visible spectroscopy and fluorescence spectroscopy. Copyright © 2006 Society of Chemical Industry

Oxidative reactions of hemoglobin (Hb) are still a serious problem for Hb-based blood substitute development. Although varieties of antioxidant strategies have been suggested, this in vitro study examined the ability of the ascorbate, N-Acetyl-L-Cysteine (NAC), 4-hydroxy-2, 2, 6, 6-tetramethylpiperidine-1-oxygen free radicals (TEMPO) and their reductant system in preventing Hb oxidation. The content of ferric Hb is monitored in the process of vitamin C (Vc), NAC, TEMPO and their reductant system. The results suggest that ascorbate is effective in reducing ferryl Hb, and TEMPO with Vc/NAC could obviously shorten the reaction time, but it does not play the role of Met-Hb reductases. It demonstrates that TEMPO did little to recover Hb under oxidative stress.

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Haemoglobin site-specifically modified with ferulic acid (FA-Hb), was synthesized. The effects on the characteristic absorption and the oxygen saturation curve of FA-Hb were investigated by UV-Vis spectrophotometry and oxygen analyzer. Furthermore, the autoxidation rates of Hb and FA-Hb were also discussed with or without sodium azide in the system. The results showed that there was no obvious transformation of the heme structure of FA-Hb. It was also demonstrated that the oxygen-carrying capacity of FA-Hb was similar to the natural Hb, but the autoxidation rate of FA-Hb was much lower than Hb in different systems.