2D scanning systems and signal study of bacteriorhodopsin photoelectric chips

• Main Authors: Yen-Chin Lin, 林彥青
• Other Authors: Hsiu-Mei Chen
• Format: Others
• Language: zh-TW
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/998ng2

碩士 === 國立臺灣科技大學 === 化學工程系 === 103 === The purple membrane (PM) of Halobacterium salinarum contains an unidirectional light-driven proton pump, bacteriorhodopsin (BR), which generates a fast (B1B2 ) and a slow (D1D2) photocurrent response upon excitation by a pulse and CW laser, respectively. This research aimed to collect and analyze those two photocurrent responses through a home-built LabVIEW-controlled automatic data acquisition system. This thesis contains two parts. First, the immobilization orientation of b-PM patches on ITO electrodes was investigated by analyzing the B1B2 photocurrent responses. A PM monolayer with nearly uniform orientation could be achieved by a fabrication process with addition of graphene oxide in the linker for PM immobilization and with a followed-up washing over the PM-fabricated chip using a shear flow. This resulted in significant enhance of B1 signals as well as reduction of B2 signals. Microarray-scanning of the as-prepared PM chips also yielded the same supportive observation. Secondly, a PM-based immuno- photoelectric array chip was developed with the D1D2 differentiation photocurrent as the measuring parameter as well as with the fact that PM photocurrents decline when the incident light is blocked by analytes. The detection of Escherichia coli using avidin-bound PM chips with and without prior immobilization of E. coli antibodies resulted in 40% and 57% photocurrent reductions, respectively. On the other hand, 50% and 23% photocurrent reductions were observed when NeutrAvidin-bound PM chips were used to detect E. coli with and without prior immobilization of E. coli antibodies, respectively. Therefore, NeutrAvidin had a lower nonspecific adsorption toward E. coli than avidin, and the prepared antibody-bound PM chips with NeutrAvidin had better detection sensitivity. Finally, simultaneous and fast detection of different organisms was demonstrated by using a LabVIEW-controlled array scanning system.