Residual dendrimer amine groups were modified with incorporate COOH group containing biomolecules such as cell adhesion peptides into collagen scaffolds. YIGSR, as a model cell adhesion peptide, was incorporated into both the bulk structure of the gels and onto the gel surface. The effects of the peptide modified collagen gels on corneal epithelial cell behavior were examined with an aim of improving the potential of these materials as tissue-engineering scaffolds. YIGSR was first chemically attached to dendrimers and the YIGSR attached dendrimers were then used as collagen crosslinkers, incorporating the peptide into the bulk structure of the collagen gels. YIGSR was also attached to the surface of dendrimer crosslinked collagen gels through reaction with excess amine groups. The YIGSR modified dendrimers were characterized by H-NMR and MALDI mass spectra. The amount of YIGSR incorporated into collagen gels was determined by 125I radiolabelling at maximum to be 3.1–3.4_10_2 mg/mg collagen when reacted with the bulk and 88.9–95.6 mg/cm2 when attached to the surface. The amount of YIGSR could be tuned by varying the amount of peptide reacted with the dendrimer or the amount of modified dendrimer used in the crosslinking reaction. It was found that YIGSR incorporation into the bulk and YIGSR modification of surface promoted the adhesion and proliferation of human corneal epithelial cells as well as neurite extension from dorsal root ganglia.

Dendrimer可以结合胶原支架，在dendrimer的氨基末端加入羧基，羧基中包含被称为YIGSR的细胞粘附多肽。YIGSR可以先与dendrimer化学连接，这种dendrimer作为胶原交联剂，使YIGSR结合到胶原凝胶中。YIGSR也可以连接到已交联dendrimer的胶原凝胶表面。经过YIGSR修饰的dendrimer用H-NMR和MALDI质谱图检测。胶原中YIGSR的含量由放射性标记¹²⁵I控制，前者最大是3.1-3.4×10^-2mg/mg,后一种连接到胶原表面是88.9-95.6ug/cm²。改变与dendrimer反应的YIGSR的量，或者改变交联反应中经过修饰的dendrimer的量，都可以调整YIGSR的含量。研究发现，经过YIGSR修饰的胶原凝胶作为一种组织工程支架能促进角膜上皮细胞的黏附和增殖，同样对背根神经节轴突的延长也有促进作用。