聚多巴胺修饰海藻酸钙微球的制备和性能探究

Preparation and functional exploration of polydopamine modified microspheres ALG@PDA

目的:通过微流控电喷雾技术和多巴胺(DA)自聚合反应制备聚多巴胺(PDA)修饰的海藻酸钙微球(ALG@PDA微球)并探究其性能。方法:微流控电喷雾技术制备海藻酸钙微球(ALG微球);DA氧化自聚合反应修饰ALG微球;光镜观察微球粒径;傅里叶变换红外光谱(FTIR)检测微球吸收峰;扫描电子显微镜观察微球表面结构;近红外激光(NIR)和热成像仪探究微球光热效应;CCK-8法、细胞活死染色检测微球浸出液处理后3T3细胞的活性;小鼠组织测试微球的黏附能力。结果:通过探究微流控参数与微载体粒径的关系,得知在一定范围内,微载体的粒径与前驱体溶液浓度、前驱体溶液流速以及毛细玻璃管尖内径成正比,而与外加电压成反比。基于微流控电喷雾技术和DA氧化自聚合反应制备出粒径200μm左右且可注射的ALG@PDA,ALG@PDA具有良好的生物相容性。得益于PDA的光热转换能力,与单纯的ALG相比,ALG@PDA具有良好的光热效应,在NIR的照射下,ALG@PDA可以在3 min时升温21.5℃。基于PDA表面丰富的儿茶酚基团,与单纯的ALG相比,ALG@PDA具有良好的黏附能力,ALG@PDA相互之间可以黏附,还可以黏附在组织表面,增加ALG@PDA在病灶的停留时间。结论:制备的ALG@PDA微球具有良好的生物相容性、光热效应和黏附性。

Objective:To prepare polydopamine(PDA)-modified Calcium alginate microspheres(ALG@PDA microspheres)by microfluidic electrospray technology and dopamine(DA)self-polymerization,and to explore their properties.Methods:Calcium alginate microspheres(ALG microspheres)were prepared by microfluidic electrospray technology,and were modified by DA oxidation auto-polymerization.The particle size of microspheres was observed by the light microscope.Fourier transform infrared spectroscopy(FTIR)was used to detect the absorption peak of microspheres.The surface structure of the microspheres was observed by scanning electron microscopy.Near-infrared laser and thermal imager were used to explore the photothermal effect of microspheres.The viability of 3T3 cells treated with microsphere leaching solution was detected by the CCK-8 method and cell live/dead staining.Mouse tissues were used to test the adhesion ability of microspheres.Results:Within a certain range,the particle size of microcarriers was proportional to the concentration of precursor solution,the flow rate of precursor solution,and the inner diameter of capillary glass tube tip,but inversely proportional to the applied voltage.Based on the microfluidic electrospray technology and DA oxidation selfpolymerization reaction,the injectable ALG@PDA with a particle size of about 200μm and ALG@PDA has good biocompatibility.Thanks to the photothermal conversion ability of PDA,ALG@PDA had good photothermal effect compared with ALG alone,and ALG@PDA can be heated up to 21.5℃in 3 min under NIR irradiation.Based on the plentiful catechol groups on the surface of PDA,compared with ALG alone,ALG@PDA had good adhesion ability,which could adhere to each other and to the tissue surface,thus increasing the residence time of ALG@PDA in the lesion.Conclusion:The prepared ALG@PDA microspheres have good biocompatibility,photothermal effect,and adhesion.