| AVS 62nd International Symposium & Exhibition | |
| Surface Modification of Materials by Plasmas for Medical Purposes Focus Topic | Thursday Sessions |
| Session SM+AS+BI+PS-ThA |
| Session: | Plasma Processing of Biomaterials and Biological Systems |
| Presenter: | Yoshihisa Ikeda, Ehime University, Japan |
| Authors: | Y. Ikeda, Ehime University, Japan M. Jinno, Ehime University, Japan |
| Correspondent: | Click to Email |
One of the physical methods that uses discharge plasma irradiation was invented by Satoh, who is one of the authors, and his group in 2002. Since this technique is free from adverse effect associated with viruses, there are no risks as the others mentioned above. The plasma irradiation on genes and cells induces the transfection process in which the genes and cells are exposed to discharge current, charged particles and chemically reactive species.
The authors investigated the factors for plasma gene transfection by changing protocols and looked at the time periods the factors become effective. The results is that transfection rate drops to 1/10 of the standard protocol when the charged particles and chemically reactive species genes are washed out from the wells by PBS solution 60s after plasma irradiation. Since the life times of the charged particles delivered from plasma to the plasmid solution is less than 60s, the direct effect of the charged particles causing transfection finishes before wash out process. This means that nearly 1/10 of transfections occur during plasma irradiation and that the last 9/10 of transfections occur after plasma irradiation is stopped. This second stage transfection is mainly caused by the residual chemically reactive species, however, plasma irradiation stress to cells and plasmids also induces transfection., i.e. possibly charging effect and oxidation stress induce bio-chemical process of the cells in addition to the chemical reactions on the cell membrane and plasmid induced by chemically reactive species such as radicals.