Summary Cancer is the second leading cause of death in the United States. Many of the cancer drugs exhibit systemic and non-selective toxicity to all tissues. To limit systemic toxicity of cancer drugs, chemical and biological targeting has been proposed. In targeted approaches, the drugs are delivered to a specific location (i.e. only cancer cells) using targeting moieties, such as antibodies, aptamers, small protein scaffolds, peptides, and small molecule ligands. Currently, targeted methods are in clinical use and under investigation; however, success has been limited. The goal of this proposal is to develop a new, generic, targeting-free drug delivery method for localized cancer that in the future can result in more effective and less toxic treatments than current methodologies. Our approach relies on cell selection process controlled by externally induced temperature difference between the targeted cells and the adjacent cells. Drug delivery is facilitated by a peptide-based drug carrier, specifically designed to fold into triple helical conformation at temperatures lower than 37C and penetrate cellular membrane only when folded. Thus, when in a coiled, non-helical conformation (above 37C), the peptide cannot be internalized by the cells (OFF switch). When the temperature is lower than the folding temperature, the peptide will undergo coil-to-helix transition and assemble into triple helix. The peptide in the helical conformation can be internalized by the cell (ON switch). In addition we propose to develop cooling device that can externally-induce temperature difference between the targeted cells and the adjacent cells to assist with the temperature-responsive peptide nanocarrier uptake to malignant cells. This proposal aims to establish thermal discrimination conditions of nanocarrier delivery to selected cancer cells (MCF-7, A495, FaDu), determine peptide nanocarrier folding kinetics and correlate it with cellular uptake. This aim will be accomplished using Circular Dichroism (CD) spectroscopy and the flow chamber equipped with syringe pump to mimic conditions in vivo. In addition, we aim to design and test cooling device to locally control temperature gradient to assist the delivery. The developmental objective is to increase the PI's involvement in interdisciplinary research directly related to human health and to increase the productivity of the PI laboratory. The requested support will result in the development of new methodologies and protocols that incorporate many scientific fields, including synthetic chemistry, cell biology, and engineering. This will directly increase participation of graduate (MS) and undergraduate students, including students from traditionally underrepresented backgrounds. This SC3 support, if awarded, will increase the PI's research output and improve competitiveness for major grant support such as NSF and NIH-RO1 type grants.