Fluorescent aptasensor for the determination of Salmonella typhimurium based on a graphene oxide platform.

Duan, Ying; Ning, Yi; Song, Yang; Deng, Le

We report on an aptamer with high affinity against Salmonella typhimurium ( S. typhimurium) and selected from an enriched oligonucleotide pool by a whole-cell SELEX process in a method for the fluorimetric determination of S. typhimurium using a graphene oxide platform. In the absence of target, the fluorescence was fairly weak as result of the FAM-labeled aptamer adjacent to graphene oxide. If, however, the fluorophore is released from the graphene oxide due to the formation of the target/aptamer complexes, fluorescence intensity is substantially increased. Under the optimum conditions, the assay displays a linear response to bacteria in the concentration range from 1 × 10 to 1 × 10 CFU·mL, with a detection limit of 100 CFU·mL. The method is selective in that fluorescence is not much enhanced in case of other bacteria. This aptasensor displays higher sensitivity and selectivity than others and is believed to possess a large potential with respect to the rapid detection of bacteria. [Figure not available: see fulltext.]

FLUORESCENCE; SALMONELLA typhimurium; GRAPHENE oxide; CHEMICAL affinity; OLIGONUCLEOTIDES; BIOLOGICAL assay

Microchimica Acta, 2014, Vol 181, Issue 5/6, p647

0026-3672

Academic Journal

10.1007/s00604-014-1170-4