Kamada K, Yamada A, Kamiuchi M, Tokunaga M, Ito D, Soh N
Graduate School of Engineering, Nagasaki University, Nagasaki, Japan.
Graduate School of Engineering, Nagasaki University, Nagasaki, Japan.
Methods Enzymol. 2016;571:113-34. doi: 10.1016/bs.mie.2016.03.002. Epub 2016 Apr 6.
Synthesis and cooperative functions of hybrid materials composed of enzyme and semiconducting layers are described in this chapter. The hybrids were produced via a simple physical interaction between the components, that is, electrostatic interaction in an aqueous solution. To form interstratifying enzymes in the galleries, solution pH, which is a key parameter to decide surface potential, should be adjusted appropriately. In other words, enzymes should have an opposite charge when compared to that of the layers at an identical pH. Even though the intercalation slightly reduced enzymatic activity as compared to those of the free enzymes, stability under cruel conditions was drastically improved due to screening effect of semiconducting layers from extrinsic stimuli. In addition, photochemical control of redox enzymes sandwiched between semiconducting layers was accomplished. Light irradiation of the hybrids induced band gap excitation of the layers, and holes produced in the valence band activated the enzymes. It was revealed that the semiconducting layers with magnetic elements might be useful to magnetic application (separation) of enzymes as similar to conventional magnetic beads.
本章描述了由酶层和半导体层组成的杂化材料的合成及其协同功能。这些杂化物是通过各组分之间简单的物理相互作用制备的，即在水溶液中的静电相互作用。为了在层间形成插层酶，作为决定表面电位的关键参数，溶液pH值应适当调节。换句话说，在相同pH值下，酶应与层带相反电荷。尽管与游离酶相比，插层作用会使酶活性略有降低，但由于半导体层对外界刺激的屏蔽作用，在恶劣条件下的稳定性得到了显著提高。此外，还实现了对夹在半导体层之间的氧化还原酶的光化学控制。对杂化物进行光照会引起层的带隙激发，价带中产生的空穴会激活酶。结果表明，含有磁性元素的半导体层可能与传统磁珠一样，对酶的磁性应用（分离）有用。
