Tissue loss has traditionally been viewed as irreversible and treatments comprised tissue replacement (by e.g. an engineering device, transplant, or graft). It has been discovered, however, that synthesis of physiologic tissue can be induced by simple chemical analogs of extracellular matrices synthesized by graft copolymerization of a glycosaminoglycan onto type I collagen. The graft can grow out of the host tissue. In this project, TOF-SIMS imaging is being used to determine the distribution of the glycosaminoglycan in the host collagen.