The RGD peptide is a popular peptide targeting motif used in experimental, nanoscale drug delivery vehicles (such as liposomes, micelles, nanoparticles, etc.) The RGD peptide binds specifically with cell adhesion molecules on the cell surface. Upregulation/overexpression of the cell surface markers on certain kinds of cancer leads to selective accumulation of nanomaterial drug carriers within cancerous tissues. Shown is the cyclic analogue of the RGD peptide complexed with alpha 5 Integrin.