Caseli Luciano, Crespilho Frank N, Nobre Thatyane M, Zaniquelli Maria Elisabete D, Zucolotto Valtencir, Oliveira Osvaldo N
Instituto de Física de São Carlos, Universidade de São Paulo, São Carlos, São Paulo, Brazil.
J Colloid Interface Sci. 2008 Mar 1;319(1):100-8. doi: 10.1016/j.jcis.2007.12.007. Epub 2007 Dec 14.
The immobilization of enzymes in organized two-dimensional matrices is a key requirement for many biotechnological applications. In this paper, we used the Langmuir-Blodgett (LB) technique to obtain controlled architectures of urease immobilized in solid supports, whose physicochemical properties were investigated in detail. Urease molecules were adsorbed at the air-water interface and incorporated into Langmuir monolayers of the phospholipid dipalmitoyl phosphatidyl glycerol (DPPG). Incorporation of urease made DPPG monolayers more flexible and caused the reduction of the equilibrium and dynamic elasticity of the film. Urease and DPPG-urease mixed monolayers could be transferred onto solid substrates, forming LB films. A close packing arrangement of urease was obtained, especially in the mixed LB films, which was inferred with nanogravimetry and electrochemistry measurements. From the blocking effect of the LB films deposited onto indium tin oxide (ITO) substrates, the electrochemical properties of the LB films pointed to a charge transport controlled by the lipid architecture.
将酶固定在有序二维基质中是许多生物技术应用的关键要求。在本文中,我们使用朗缪尔-布洛杰特(LB)技术获得了固定在固体支持物上的脲酶的可控结构,并对其物理化学性质进行了详细研究。脲酶分子吸附在空气-水界面,并掺入磷脂二棕榈酰磷脂酰甘油(DPPG)的朗缪尔单分子层中。脲酶的掺入使DPPG单分子层更具柔韧性,并导致膜的平衡弹性和动态弹性降低。脲酶和DPPG-脲酶混合单分子层可以转移到固体基质上,形成LB膜。通过纳米重力测量和电化学测量推断,尤其是在混合LB膜中,获得了脲酶的紧密堆积排列。从沉积在氧化铟锡(ITO)基板上的LB膜的阻断效应来看,LB膜的电化学性质表明电荷传输受脂质结构控制。