An enzyme-free and label-free visual sensing strategy for the detection of thrombin using a plasmonic nanoplatform

Analyst. 2020 Mar 21;145(6):2219-2225. doi: 10.1039/c9an02340b. Epub 2020 Feb 18.

Abstract

An enzyme-free and label-free visual sensing strategy was developed for sensitively detecting thrombin using a plasmonic nanoplatform. Both the thrombin-triggered catalytic hairpin assembly (CHA) amplification reaction and G-quadruplex/hemin DNAzyme-controlled plasmonic signal readout were engineered on an electrospun nanofibrous membrane. Owing to its large specific surface area and porous structure, the nanofibrous membrane enhanced the loading capacity of B-H2 and the interface interaction efficiency. This plasmonic nanoplatform was used to perform the sensitive and naked-eye detection of thrombin as low as 1.0 pM in human serum samples. This visual strategy can discriminate thrombin from other co-existing proteins very well. Moreover, the visual sensing platform exhibited excellent reusability and long-term stability. The proposed enzyme-free and label-free plasmonic nanoplatform is low-cost, easy to operate and highly sensitive, and has potential applications in the point-of-care detection of protein biomarkers.

MeSH terms

  • Aptamers, Nucleotide / chemistry*
  • Biosensing Techniques / methods*
  • DNA, Catalytic / chemistry
  • G-Quadruplexes*
  • Hemin / chemistry
  • Humans
  • Limit of Detection
  • Nanofibers / chemistry
  • Thrombin / analysis*

Substances

  • Aptamers, Nucleotide
  • DNA, Catalytic
  • thrombin aptamer
  • Hemin
  • Thrombin