Hybrid Nanotubes (HyNTs)-Based Intracellular Molecule Delivery

Delivering biomolecules into living cells has become an important challenge in medical and biological fields. Conventional techniques such as virus vector and electroporation are utilized commonly for small molecule delivery, but still remain several problems of low efficiency and low viability for large molecules such as biological proteins and organelles. To overcome this problem, we demonstrate the macromolecular delivery into adhesive cells with metallic nanotube ducts. The metallic nanotubes were developed by an electroless plating of gold onto track-etched polycarbonate template and wet/dry etching [1]. To insert Au nanotubes into the cells (such as HeLa and NIH3T3), we developed the height control system with the fluorescent microscope.<br/>Furthermore, by coating the surface of this nanotube with a conductive polymer (PEDOT), we developed a novel Au nanotube/PEDOT, which is hybrid nanotubes (HyNTs), that promotes the flow of ions at an applied voltage (about 50 mV) below the cell membrane potential [2]. As a result, we have succeeded in developing an electric nanoinjector that delivers macromolecules such as green fluorescent protein (GFP) and DNA plasmid into cells.<br/><br/>[1] Bowen Zhang, Yiming Shi, Daisuke Miyamoto, Koji Nakazawa, Takeo Miyake, “Nanostraw membrane stamping for direct delivery of molecules into adhesive cells”, Scientific Reports, 9, 6806, 2019.<br/>[2] Bowen Zhang, Dinuo Zheng, Shi Yiming, Kazuhiro Oyama, Masahiro Ito, Masaomi Ikari, Takanori Kigawa, Tsutomu Mikawa, Takeo Miyake, “High-Efficient and Dosage-Controllable Intracellular Cargo Delivery through Electrochemical Metal-Organic Hybrid Nanogates”, Small Science, 10, 1002, 2021.