APPLICATION OF BIOMATERIALS IMMOBILIZED WITH BIOSIGNAL MOLECULES

用于控制组织或细胞与生物材料之间的界面的方法可以分为两类。一种是材料的生物化，另一种是化学修饰。生物化包括固定化抗凝剂或用于血液相容性的血液内皮细胞杂交，或固定化细胞粘附肽以用于细胞粘附剂。此外，细胞生长因子蛋白的固定化增强了细胞的生长。生物信号蛋白的固定化使生物材料能够调节细胞的各种功能，如分化、分泌和运动。化学修饰包括表面亲水或疏水，或电化学修饰。聚合物科学的最新进展使材料表面的时空控制成为可能。细胞的位置可以通过表面的光刻修饰来调节，细胞的附着和分离可以通过热敏聚合物…的温度操纵来控制更重要的是，表面进行了生物处理，以促进生长和促进分化。此外，通过生物和化学相结合的方法实现了时空可控的智能生物材料。这种智能生物材料不仅可用于医学应用，还可用于生物传感器和纳米生物技术的基本方法。表面生物化是通过固定化细胞生长因子蛋白、胰岛素和表皮生长因子实现的。EGF是一种膜结合型生长因子，可通过“旁分泌刺激”刺激细胞而不扩散。固定化胰岛素和EGF对细胞生长的促进作用强于游离胰岛素或EGF。在嗜铬细胞瘤(PC12)细胞培养中，固定化EGF促进神经分化，但不促进生长，而游离EGF促进细胞生长。刺激方式(旁分泌和旁分泌)切换基因表达。利用温敏聚合物制备了时间可控的智能生物材料。通过与胰岛素的结合，通过降温将促进细胞生长的生物材料与生长的细胞分离，通过模式固定化热响应聚合物、胰岛素和EGF实现空间可控生物材料，在低温下观察到生长细胞在微图案化的热响应聚合物上的选择性分离。在用胰岛素或EGF固定的特定区域观察到选择性的信号转导。该技术有助于显示固定的生物信号对旁分泌刺激的作用。较少

Approaches for controlling the interface between tissue or cells and biomaterial can be divided into two categories. One is biolization of materials another chemical modification.Biolization invloves immobilization of anticoagulant or hybridization of blood endothelial cells for blood-compatibility, or immobilization of cell adhesive reptide for cell adhesives. In addition, immobilization of cell growth factor proteins enhances cell growth. The immobilization of biosignal proteins enables biomaterials to regulate various functions of cells, such as differentiation, secretion, and motility.Chemical modification involves surface hydrophilization or hydrophobilization, or electrochemical modification. Recent progress of polymer science has enabled space-time control of material surface. The position of cells can be regulated by photo-lithographic modification of the surface and the attachment and detachment of cells can be controlled by temperature manipulation of a thermo-sensitive polym … More er.Herein the surface was biolized for growth enhancement and differentiation promotion. In addition, space-time controlled intelligent biomaterials were achieved by the combination of biological and chemical approches. The intelligent biomaterials will be useful not only for medical applications but also for fundamental methodologies of biosensors and nano-biotechnology.Surface biolization was achieved by immobilization of cell growth factor proteins, insulin and epidermal growth factor (EGF). EGF is a membrane-bound growth factor which can stimulate cells without diffusion in medium by "juxtacrine stimulation". Immobilized insulin and EGF enhanced cell growth more than free insulinor EGF.In the culture of pheochromocytoma (PC12) cells, the immobilized EGF promoted neural differentiation but did not enhance the growth, although free EGF enhanced growth. The stimulation mode (juxtacrine and paracrine) switched the gene expression.Time-controlled intelligent biomaterial was prepared usinf thermo-sensitive polymer. By combination with insulin, the biomaterial enhanced cell growth and the grown cells were detached by lowering temperature.Spatial controlled biomaterial was achieved by pattern immobilization of thrermo-responsive polymer, insulin, and EGF.Selective detachment of growth cells was observed on the micro-patterned thermo-responsive polymer at a low temperature. Selective signal transduction was observed on th specific area immobilized with insulin or EGF.The technique was useful for visualization of juxtacrine stimulation by immobilized biosignals. Less