Analysis of the heterogeneous structure of iron oxide/gold nanoparticles and their application in a nanosensor

作者：Bustami Y^*; Moo Young M; Anderson W A

来源：Sensors and Actuators B: Chemical , 2017, 245: 753-764.

DOI：10.1016/j.snb.2017.01.142

• IONPs/AuNPs
• Electrostatic self-assembly
• Glucose oxidase immobilization
• Glucose detection

Magnetic iron oxide-gold nanoparticles (IONPs-AuNPs) could provide a useful platform for biosensing purposes. The aim of this study was to investigate the formation of such particles using a simple electrostatic self-assembly technique, and then to demonstrate their application using a glucose detection assay. AuNPs were attached to the IONPs surface by ionic interaction, as verified using UV-vis spectrophotometry. Then, a carbodiimide-coupling technique was used to covalently attach glucose oxidase (GOx) onto the nanoparticles' surface and the bioactivity was measured using an ABTS colorimetric assay. For characterization, UV-vis spectrophotometer, DLS, zeta potential, TEM, EDX, XPS and FTIR techniques were used. The particle diameter obtained from TEM was 16.1 +/- 11.1 nm and EDX confirmed the presence of Au and Fe elements. In addition, FTIR results exhibited strong vibrational modes around 1654, 1546 and 3369 cm(-1) that appeared to be primarily due to immobilization of GOx onto Fe/Au. The colorimetric assay also showed a significant increase in green color intensity, due to oxidation of ABTS, with increasing glucose concentrations ranging from 20 mu M to 100 mu M. IONPs/Au nanoparticles showed a good potential for application in this colorimetric assay, thus suggesting an excellent basis for a nanosensor system using these particles.

• 出版日期2017-6