The chemical coupling of growth factors to solid substrates are discussed as an alternative to delivery systems. Utilizing entire proteins for this application is hampered by safety and stability considerations. Instead, growth factor mimicking peptides are of great interest for biomedical applications, such as tissue engineering, due to their purity and stability. The human cathelicidin derived antimicrobial peptide LL37, beside its microbicidal activity, was shown to stimulate endothelial cell growth when used in a soluble form. Here, in a novel approach, spacer mediated immobilization, but not direct conjugation of LL37, to a gold substrate was shown to result in a pronounced mitogenic effect on endothelial cells, comparable to that of soluble vascular endothelial growth factor.