Establishment of a new method based on nucleic acid functionalized GO for the rapid detection of Salmonella typhimurium carrying SSeC gene / 中华微生物学和免疫学杂志

ABSTRACT

Objective To establish a simple, efficient and low-cost method for the detection of Salmonella typhimurium carrying SSeC gene. Methods In this study, a nano-biosensor ( FAM-P/GO) was successfully established based on the noncovalent assembly of carboxy-fluorescein ( FAM)-labeled probe and graphene oxide ( GO) . The target gene at different concentrations and SSeC gene-harbored bacterium sam-ples were detected by the FAM-P/GO nano-biosensor to evaluate its sensitivity. The specificity of the estab-lished nano-biosensor was evaluated by using DNAs with mismatched base pairs and single-stranded DNAs ( ssDNAs) extracted from various species. Results The established strategy for SSeC gene detection showed a good linear range of 0. 05-1. 0 μmol/L (R2=0. 992 1) with a lower limit of 0. 05 μmol/L. Moreover, the lower detection limit for target bacterium samples was 103 CFU/ml and the fluorescence intensity increased linearly with the concentration from 103 CFU/ml to 108 CFU/ml. The signal-to-noise ( S/N) of the experi-mental group was much greater than that of the control group, which indicated that the establish method was highly specific. Conclusion The FAM-P/GO nano-biosensor was successfully established in this study, which provided a new and possible way for the rapid detection of Salmonella typhimurium harboring SSeC gene.