甘露糖修饰的微马达的制备及其免疫功能初探

In order to develop a novel sugar hybrid material with self-actuated micromotor and immune function, we designed and prepared a dumbbell micromotor modified with mannose (Zinc oxide/Polydopamine/Mannose micromotor, ZnO/PDA/Man micromotor for short), which combines the kinetic properties of ZnO active colloid and visible light absorption properties of PDA materials. X-ray diffraction (XRD) and Raman spectroscopy results showed that the introduction of PDA and Man does not change the crystal shape of ZnO, which ensures that the photocatalytic activity of ZnO is unaffected in ZnO/PDA/Man. The dumbbell structure of the micromotor can cause an uneven distribution of ions, the ion gradient will drive micromotor to move. The micromotor energy source is non-toxic and can move itself in solution with pure water as fuel under visible light. The simulation verified that the motion mechanism of dumbbell micromotor is ionic self-diffusiophoresis, which keeps the head in front and pulls the colloid to move. The motion behavior of the micromotor under different intensities of visible light was observed and recorded by the microscope. It was found that the micromotor changed from translational motion to circular motion with the enhancement of light intensity, and the micromotor’s motion speed also increased gradually. Meanwhile, by adjusting the direction of incident light, the motion direction of ZnO/PDA/Man micromotor can be accurately adjusted to make it move according to the predetermined route. In order to preliminarily explore whether the mannose-modified micromotor can regulate the phenotype of macrophages, the ZnO/PDA/Man micromotor was incubated with macrophages, and the morphological changes of macrophages were observed with a microscope. The results showed that the micromotor could be used as an immune activator to polarize macrophages. What’more, cytotoxicity experiment indicated that ZnO/PDA/Man micromotor has good biocompatibility. Compared with traditional immune activators, ZnO/PDA/Man micromotor is expected to realize free movement in tumor tissues under visible light irradiation, so as to promote their deep penetration into tumor tissues, which has potential application in the field of tumor immunotherapy.