Nanomaterial-based intracellular delivery systems

Abstract

Techniques for the delivery foreign materials into living cells as well as for sensing have undeniable worth in cell biology research. One-dimensional nanonedles are one of the promising methods for insertion with minimal invasiveness to a cell. Additionally, most studies were done to date have used either a vertical nanoneedle. I synthesized newly inclined nanoneedles and demonstrated a novel platform using inclined-gallium nitride nanoneedles (iGaN NNs) to facilitate efficient intracellular delivery. In our system, the cellular membrane is efficiently penetrated by the iGaN NNs compared to the vertical NNs. Among diverse MOF, zeolitic imidazolate framework-8 (ZIF-8) has excellent biocompatibility, biodegradability by pH-sensitive behavior, and encapsulation capability, which is one of the ideal nanocarrier for drug delivery. I have developed HA-coated FD 70k@ZIF-8 NPs with high cellular uptake. The ZIF-8 is used to encapsulate biomimetic FITC dextran and pH-responsive platform. Then, HA is easily coated on the outer layer of the FD 70k@ZIF-8 NPs through electrostatic interaction in order to selectively target cancer cells. Cellular uptake based on the interaction between HA and the CD44 receptor improved and demonstrated. Among the nanoneedle-based intracellular delivery studies, there is intracellular delivery through cultivation of cells on nanostructures. However, the substances could be conjugated to the surface of nanostructures via organic synthesis. To solve this problems, I suggest that a novel intracellular delivery system. FITC was encapsulated in ZIF-8@ZnO nanoneedles without any organic synthesis for intracellular delivery. I demonstrated that this technique is applicable to deliver various molecules in a cell regardless of cell lines. In conclusion, I have studied intracellular delivery using various nanomaterials-based methods (iGaN nanoneedle, ZIF-8 nanoparticles, ZIF-8@ZnO nanoneedle) in vitro. These methods effectively delivered the foreign substances into the cell with high cell viability. Thus, these methods may provide new route for universal biological application in vitro.