Label-free graphene oxide–based SPR genosensor for the quantification of microRNA21

MUJICA, MICHAEL LÓPEZ; ZHANG, YUANYUAN; BÉDIOUI, FÉTHI; GUTIÉRREZ, FABIANA; RIVAS, GUSTAVO

Analytical and Bioanalytical Chemistry

SPRINGER HEIDELBERG

Año: 2020 vol. 412 p. 3539 - 3539

1618-2642

his work is focused on the development of a genosensor for microRNA-21 quantification using surface plasmon resonance (SPR) to transduce the hybridization event. The biosensing platform was built by self-assembling two bilayers of poly(diallyldimethylammonium chloride) (PDDA) and graphene oxide (GO) at a gold surface modified with 3-mercaptopropane sulfonate (MPS), followed by the covalent attachment of the DNA probe. GO was used in two directions, toallow the anchoring of the probe DNA and to increase the sensitivity of the biosensing event due to its field enhancer effect. The new bioanalytical platform represents an interesting alternative for the label-free biosensing of microRNA-21, with a linear range between 1.0 fM and 10 nM, a sensitivity of 5.1 ± 0.1 moM−1 and a detection limit of 0.3fM. The proposed sensing strategy wassuccessfully used for the quantification of microRNA-21 in enriched urine samples.