基于戊二醛偶联技术制备脲酶-Au-MMP“双面神”酶驱动马达及其运动性能

Fabrication of urease-Au-MMP Janus enzyme-powered micromotors based on glutaraldehyde coupling technology and their motion behaviors

采用磁控溅射技术在磁性微球的半球上溅射Au层,得到Au-磁性微球(MMP)粒子;在Au侧依次偶联半胱胺、戊二醛(GA)和脲酶制备脲酶-Au-MMP“双面神”酶驱动马达;并采用场发射扫描电子显微镜、能谱仪和光学显微镜对马达形貌、成分以及运动性能进行表征。结果表明:脲酶-Au-MMP马达呈“双面神”结构,Au侧表面粗糙;C和Fe元素均匀分布在整个球体上,Au元素只分布在马达的半球上;脲酶不对称修饰在马达的半球上;尿素燃料浓度的提高可以有效提高马达的运动速率,当尿素浓度为10mmol/L时,其运动速率可达3.75μm/s;马达是以磁性微球作为基体,其运动方向可以通过外部磁场的进行精确控制。

Herein,we fabricated the Janus magnetic microspheres (MMPs) by asymmetrically sputtering a thin Au layer on the MMPs.Then,the urease molecules were immobilized on the Au surface by using cysteamine and glutaraldehyde (GA) as linker molecules.Scan electron microscope (SEM),energy dispersive X-ray spectroscopy (EDS),and optical microscope were used to characterize the structure,component and motion behaviors of the as-obtained enzyme-powered urease-Au-MMP Janus motors.The results show that the as-obtained enzyme-powered urease-Au-MMP Janus motors have a Janus structure and the surface of the Au side is rough.The C and Fe elements are evenly distributed on the whole sphere,while the Au element is only distributed on the hemisphere of the enzyme-powered urease-Au-MMP Janus motor.The ureases are asymmetrically modified on the hemisphere of the enzyme-powered urease-Au-MMP Janus motor.The velocity of the enzyme-powered urease-Au-MMP Janus motors can be enhanced effectively with the increase of the urea concentration.When the concentration of urea reaches at 10 mmol/L,the velocity of the enzyme-powered urease-Au-MMP Janus motors can be increased to 3.75 μm/s.In addition,the motor is made from magnetic microspheres,so the direction of motion of the motor can be precisely controlled by an external magnetic field.