FUNCTIONALIZED PARTICLES FOR LABEL-FREE DNA IMPEDIMETRIC BIOSENSOR FOR DNA AND RNA SENSING

摘要

In one embodiment, 3-Aminopropyltriethoxysilane (APTES) functionalized graphene oxide (APTES-GO) wrapped SiO₂ particle composite (SiO₂@APTES-GO) was prepared via the self-assembly process of APTES-GO sheets and SiO₂ particles. Transmission electron microscopy (TEM) and Attenuated Total Reflectance-Fourier Transform Infrared spectroscopy (ATR-FTIR) confirmed wrapping of the SiO₂ particles by the APTES-GO sheets. A biosensor based on electrochemical impedance spectroscopy (EIS) was constructed and used to sensitively detect dengue DNA and dengue RNA via primer hybridization using different oligonucleotide sequences. The results demonstrated that the SiO₂@APTES-GO electrode material led to enhanced sensitivity, selectivity and detection limit, compared to both APTES-GO and APTES- S1O2. The three-dimensional structure, high surface area, electrical properties and the ability for rapid hybridization offered by the SiO₂@APTES-GO rendered this electrode material as ideal to use in the reported dengue impedimetric sensor.