Development of purple membrane-based photoelectric chips to detect Fungi, Gram-negative and Gram-positive bacteria detection

• Main Authors: Yin-De Lai, 賴銀德
• Other Authors: Hsiu-Mei Chen
• Format: Others
• Language: zh-TW
• Published: 2019
• Online Access: http://ndltd.ncl.edu.tw/handle/ce3z3f

碩士 === 國立臺灣科技大學 === 化學工程系 === 107 === Untreated bacteremia patients are at high risk of developing acute multiple-organ metastatic infection. Early identification of infectious microorganisms as fungus, gram-negative bacteria, or gram-positive bacteria help narrow the antibiotics treatment, and avoid the development of antibiotic resistance. Halobacterium salinarum purple membrane (PM) contain bacteriorhodopsin, a light-driven proton pump able to transport protons across PM upon illumination and subsequently generate photocurrents. According to the linear dependence of PM photocurrents on illumination intensities, we had developed a series of different PM-based biosensors. This thesis comprises four parts. First, a PM chip coated with chitin-aptamers to detect fungi with optimization investigation. Secondly, antibodies against lipoteichoic acid (LTA) were immobilized on a PM chip to capture gram-positive bacteria. Thirdly, another immunosensing PM-based chip was constructed with antibodies against lipopolysaccharide (LPS) to recognize gram-negative bacteria. Finally, the performance of those three chips were investigated with seven bacteremia strains most commonly prevalent in Taiwan, demonstrating their differential recognition ability among fungi, gram-negative bacteria, and gram-positive bacteria. The newly developed PM-based bacteremia biosensor has the advantages of direct and fast detection with high sensitivity, and can be applied to rapid screening in the future.