서강대학교

초록/요약

Viruses are the agents of most destructive diseases afflicting animals and plants. The Human immunodeficiency virus (HIV) is well known variants which causes the AIDS in human and affects the immune system to allow life-threatening infections. To understand the phenomena and find a cure for AIDS, the HIV was intensively studied over the years. In this study, nano scale prtoein chip is developed to detect HIV-1 virus based on immunoreactions. To determine the HIV-1 Virus, HIV-1 Virus like particles (HIV-1 VLPs) was produced by cotransfection of HEK293 T cells with two different plasmids, pCMV-dR8.74 and pDOLHIVenv, which contain Gag and Pol, and Env components of HIV-1, respectively. The produced HIV-1 VLPs were determined by energy-filtering transmission electron microscope and ELISA. Further, Using HIV-1 VLPs, comparative efficiency was determined by several other methods, such as electrical detection by scanning tunneling microscopy, electrochemical detection system by cyclic voltammogram, and plasmonic detection by localized surface plasmon resonance and surface enhanced raman spectrocopy. Fragmented antibody, which contains native thiol (-SH) group was applied to the Au surface for oriented immobilization. Moreover, electrochemically fabricated Au nanostructure and Au nanoparticle-antibody complex had improved the sensitivity and selectivity of sensor device. STM was applied to develop vertically configured electrical detection system. In the electrochemical detection, the 3-D nano structure enhances the electrical property due to their higher surface-to-volume ratio, which makes electrode to susceptible to external influences, especially when their size continues to reduce to atomic level. Since the dimensions of nanostructure become comparable to the size of the target biomolecules, measurement sensitivity will increase, and also this due to higher capture efficiency. Furthermore, fabricated Au nanopattern produces localized plasmon by induced electromagnetic field. This plasmon provides a very sensitive probe to detect small changes in the dielectric environment around the nanostructures, which is particularly attractive for sensing applications. Local refractive index changes induced by biomolecular interactions at the surface of the nanostructures were monitored by the LSPR peak changes. Due to the difference in dielectric constants between the Au nanopattern and the surrounding media, the changes in the biological components on the Au nanopatterned ITO substrate could be distinguished by different SERS peaks observed on a spectrum. From the results, it is concluded that to detect HIV-1 virus plasmonic detection method is the most suitable for developing a protein based chip. Moreover, the proposed techniques could be extended to detect various kinds of human diseases.