A composite of 3-Aminopropyltriethoxysilane (APTES) functionalized graphene oxide (APTES-GO) wrapped on SiO2 particles (SiO2@APTES-GO) was prepared via self-assembly. Transmission electron microscopy (TEM) and ATR-Fourier Transform Infrared spectroscopy (ATR-FTIR) confirmed wrapping of the SiO2 particles by the APTES-GO sheets. An impedimetric biosensor 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 dengue RNA detection sensitivity with selectivity and detection limit (1 femto-Molar), compared to both APTES-GO and APTES-SiO2. The three-dimensional structure, higher contact area, electrical properties and the ability for rapid hybridization offered by the SiO2@APTES-GO led to the successful design of a dengue biosensor with the lowest detection limit reported to date.
Jin, S. A., Poudyal, S., Marinero, E. E., Kuhn, R. J., & Stanciu, L. A. (2016). Impedimetric Dengue Biosensor based on Functionalized Graphene Oxide Wrapped Silica Particles. Electrochimica Acta, 194, 422–430. https://doi.org/10.1016/j.electacta.2016.02.116