Dual colormetric and fluorescent sensor for detection of glucose via Fe3O4-mediated catalytic reaction.

• Main Authors: Wei-Kai Tsai, 蔡威凱
• Other Authors: Wei-Lung Tseng
• Format: Others
• Language: zh-TW
• Published: 2019
• Online Access: http://ndltd.ncl.edu.tw/handle/6hs4r9

碩士 === 國立中山大學 === 化學系研究所 === 107 === Iron nanoparticles are usually used as peroxidase-mimic materials and combined with Glucose oxidase to measure glucose. Glucose oxidase catalyzes glucose to generate H2O2, which in turn is catalyzed by Fe3O4 nanoparticles to produce hydroxyl free radicals as an intermediate. Then, the·OH captures a H+ from the hydrogen donor to catalyze colorimetric reaction and to determine the concentration of glucose. For example, o-Phenylenediamine (OPD) can be oxidized to 2,3-Diaminophenazine by H2O2. In this study, we found that the ferrous ion chelated by Horseradish Peroxidase can catalyze the synthesis of benzimidazole derivates from OPD in the presence of O2 and glucose, which gives strong absorption and fluorescence intensity, as the dual colorimetric and fluorescent sensor of glucose. In order to enhance the stability of catalyst, we prepared the porous Fe3O4 nanospheres composed of small iron nanocrystals and carbon dots via one-pot solvothermal method. Fe3O4 nanoparticles can catalyze OPD and glucose to replace the native HRP enzyme. Organic molecules would form the carbon quantum dots, which capping on the iron nanocrystals, under the high temperature. The interaction between the carbon dots induce self-assembly of the primary iron crystals to form larger and porous nanospheres, followed with the enhancement of catalytic ability. Histidine carbon dots - modified Fe3O4 nanoparticles mimic the heme structure and show comparable activity to naked one. We use ESI to prove the formation of benzimidazole derivative in the presence of glucose and Fe3O4 nanoparticles. Therefore, we can catalyze OPD to accelerate the glucose-derivatization by Fe3O4 nanozyme and apply it to the measurement of glucose concentration in human serum.