||In recently years, scientists have developed various self-assembled nanostructures, ranging from magnetic nanoparticles, quantum dots, to small molecule hydrogels. And it has become increasingly important to apply these materials for the benefit of mankind. In this thesis, we studied the self assembled nanostructures on the interface of biological systems and tried to develop them as candidates for either cancer therapy or wound healing. In the first part, we utilized the enzymes in mammalian cells to help the formation of nanofibers from some short chain peptide derivatives, which, after enzymatic catalysis, will self-assemble and form hydrogels intracellularly. Because of the difference of enzymatic activities between cancer cells and normal cells, these small molecules could be the candidates of prodrugs that preferentially kill cancer cells. Thus we designed and studied precursors that are susceptible to esterases, phosphatases or multiple enzymes. Furthermore, we tried to combine anti-cancer drugs with these precursors to achieve maximum potency. In the second part, we applied the small molecule hydrogels in the decorportation of uranium from the contaminated wound of mice, for the nanofibers within the matrix of these hydrogels get high surface/volume ratio and, with a conjugated ligand, can chelate with toxic ions (eg. uranyl ions) with high efficiency. Finally, we conjugated another type of nanostrucutures, magnetic iron oxide nanoparticles, with porphyrin and developed them as potential candidates for bimodal anticancer therapy: photodynamic therapy (PDT) and hyperthermia (HT).