DNA aptamer-micelle as an efficient detection/delivery vehicle toward cancer cells.

We report the design of a self-assembled aptamer-micelle nanostructure that achieves selective and strong binding of otherwise low-affinity aptamers at physiological conditions. Specific recognition ability is directly built into the nanostructures. The attachment of a lipid tail onto the end of nucleic acid aptamers provides these unique nanostructures with an internalization pathway. Other merits include: extremely low off rate once bound with target cells, rapid recognition ability with enhanced sensitivity, low critical micelle concentration values, and dual-drug delivery pathways. To prove the potential detection/delivery application of this aptamer-micelle in biological living systems, we mimicked a tumor site in the blood stream by immobilizing tumor cells onto the surface of a flow channel device. Flushing the aptamer-micelles through the channel demonstrated their selective recognition ability under flow circulation in human whole-blood sample. The aptamer-micelles show great dynamic specificity in flow channel systems that mimic drug delivery in the blood system. Therefore, our DNA aptamer-micelle assembly has shown high potential for cancer cell recognition and for in vivo drug delivery applications.