Nakashima Kazunori, Kamiya Noriho, Koda Daisuke, Maruyama Tatsuo, Goto Masahiro
Department of Applied Chemistry, Graduate School of Engineering, Fukuoka 819-0395, Japan.
Org Biomol Chem. 2009 Jun 7;7(11):2353-8. doi: 10.1039/b823064a. Epub 2009 Mar 30.
Horseradish peroxidase (HRP) is encapsulated in polymerized ionic liquid microparticles (pIL-MP), which are prepared by polymerization of 1-vinyl-3-ethylimidazolium bromide in the presence of the crosslinker N,N'-methylenebis(acrylamide) in a concentrated water-in-oil (W/O) emulsion. pIL-MP encapsulating HRP chemically-modified with comb-shaped polyethylene glycol (PM(13)-HRP) exhibit excellent activity for guaiacol oxidation in an aqueous solution. The PM(13)-HRP in pIL-MP shows more than 2-fold higher activity than that of the enzyme encapsulated in a polyacrylamide microparticle. The catalytic activity declines with an increase in the crosslinker concentration of the pIL-MP, probably due to suppression of substrate diffusion. The activity of PM(13)-HRP in pIL-MP depends on the external environment of the gel (i.e. pH and temperature). The pIL-MP are easily recovered from the reaction mixture by centrifugation, which makes it possible to recycle the biocatalyst for repeated oxidation reactions.
辣根过氧化物酶（HRP）被封装在聚合离子液体微粒（pIL-MP）中，这些微粒是通过在交联剂N，N'-亚甲基双丙烯酰胺存在下，在浓油包水（W/O）乳液中使1-乙烯基-3-乙基咪唑溴化物聚合而制备的。封装有经梳状聚乙二醇化学修饰的HRP（PM(13)-HRP）的pIL-MP在水溶液中对愈创木酚氧化表现出优异的活性。pIL-MP中的PM(13)-HRP的活性比封装在聚丙烯酰胺微粒中的酶的活性高出2倍以上。催化活性随着pIL-MP交联剂浓度的增加而下降，这可能是由于底物扩散受到抑制。pIL-MP中PM(13)-HRP的活性取决于凝胶的外部环境（即pH值和温度）。通过离心可以很容易地从反应混合物中回收pIL-MP，这使得生物催化剂能够循环用于重复氧化反应。
