Cell Membrane Perforation with Photosensitizer and a Brush-shaped Soft-polymer Sheet Using a Malignant Glioma Cell Line.

Background: Transduction of foreign molecules into cells is an important technique to investigate the functions of corresponding molecules and/or targets. Recently, a mass-producible nanoprinting perforator was devised enabling for large-scale, high-performance drug or nucleic-acid transfer into cells without cell damage. Since little is known on the performance of the system, we investigated its effects on a malignant glioma cell line.

Photodynamic cell membrane perforation for intracellular electrodes.

We report a new aspect of rapid (<10 seconds) light-induced cell membrane perforation for intracellular electrode by Hematoporphyrin (HP), which is an original photosensitizer for photodynamic therapy concept. A microelectrode insertion process to cell could be improved by pinpoint use of the photosensitizing effect to degenerate cell membranes prior to insertion. According to the concept, simple electrode coating with photosensitizer will enable intracellular electrode array for neural engineering.

Self-organized ZnO nanorod with photooxidative cell membrane perforation enables large-scale cell manipulation.

Various devices have been developed for verification and application of cellular functions in recent years. In our previous study, we found that local oxidation reactions in the cell membrane could produce submicron sizes of reversible membrane perforations in cells, while more than 80% of treated cells were viable even after perforations; therefore, to date, we have attempted some applications of this mechanism and analyzed their feasibility. In the present study, we developed a rod-shaped device in which the function of membrane perforation is added by utilizing a photosensitizer and, using the device, we have attempted to produce membrane perforations in a large number of cells.

MALC, a novel microinjection method for loading of macromolecules into cultured neurons.

Microinjection is one of the most useful and important methods in cellular neurobiology. However, direct insertion and retraction of a capillary produce physical stresses inside cells that make it difficult to apply on small and fragile cells, especially the central nervous system (CNS) neurons. In this study, we developed a novel method called MALC (microinjection method assisted with laser activated chromophore) to avoid this disadvantage of the conventional method.