| 학회 | 한국고분자학회 |
| 학술대회 | 2005년 가을 (10/13 ~ 10/14, 제주 ICC) |
| 권호 | 30권 2호 |
| 발표분야 | 의료용 고분자 부문위원회 |
| 제목 | Application of Nano-Biomaterials to Gene Delivery and More. |
| 초록 | Chitosan, a natural cationic polysaccharide containing N-acetyl-glucosamine, has been widely employed as a non-viral gene carrier for its biocompatibility and superior ability of transfection. A low charge density of chitosan, however, has decreased transfection efficiency of chitosan, compared to other cationic synthetic polymers. In this study, low molecular weight poly(ethylene imine) was chemically conjugated to chitosan chains. Size of DNA/chitosan complex increased steeply compared to DNA/PEI-g-chitosan complex because of short PEG chains grafted to chitosan polymers. The zeta-potential also shows a difference between chitosan and (PEI-PEG)-g-chitosan, suggesting nanoparticulates with between (PEI-PEG)-g-chitosan and DNA are less compact compared to chitosan nanoparticulates. (PEI-PEG)-g-chitosan/DNA complex showed increased transfection efficiencies with a statistical significance. Specifically, the superiority of (PEI-PEG)-g-chitosan/DNA complex was prominent at high N/P ratios. The increased transfection efficiency was of noticeable because many PEG-modified chitosans showed decreased transfection efficiency compared to chitosan. This can be attributed to PEI-PEG grafted on chitosan molecules. While PEG can interfere with electrostatic interactions between DNA and chitosan, PEI, however, increases cationic charge densities on chitosan, reversing interfering effects of PEG on the complex. PEI-PEG-g-chitosan is far less cytotoxic than chitosan. This can be attributed that PEG chains grafted on chitosan interfere with direct interaction between cell membranes and complexes. Synthetic inorganic gene carriers have received limited attention in the gene therapy community, the only notable example being gold nanoparticles with surface-immobilized DNA applied to intradermal genetic immunization by particle bombardment. Multifunctional metal nanorod were fabricated for gene therapy and in vitro immunization. Deposition of the nanorods was achieved by template synthesis, which involves electrochemical deposition into a non-conducting membrane having an array of cylindrical pores. Subsequent removal of the membrane by etching yields metallic nanorods of controlled dimensions. Previously, we demonstrated a new approach for gene delivery using multisegment nanorods. A gene gun was employed for immunization using multifunctional nanorods. A ring magnet also increased the penetration depth of metal nanorods, suggesting magnetic fields affected the orientation of nanorods. |
| 저자 | 유혁상 |
| 소속 | 강원대 |
| 키워드 | 나노; 바이오; 유전자; 전달 |
