Structure-switching fluorescence aptasensor for sensitive detection of chloramphenicol

Pengfei Ma, Yuhan Sun, Imran Mahmood Khan, Qian Hui Gu, Lin Yue, Zhouping Wang

Research output: Journal PublicationArticlepeer-review

22 Citations (Scopus)


The performance of chloramphenicol aptamer, including binding thermodynamics, structure switching, and binding domain, was investigated by isothermal titration calorimetry, circular dichroism, and molecular docking. Then, a new fluorescence aptasensor was developed with signal amplification mediated by exonuclease I-catalyzed reaction and hybridization chain reaction (HCR) for chloramphenicol detection. In this system, the aptamer-binding domain is blocked by the initiator of HCR, the aptamer undergoes structure switching in the presence of chloramphenicol, and DNA dissociation occurs. The released aptamer is subsequently recognized and cleaved by Exo I to set free chloramphenicol. With the Exo I-assisted chloramphenicol recycling, an increasing number of initiators were exposed from the digestion of the initiator-aptamer complex. Then, the chain-like assembly of FAM labeled H1 and H2 through HCR was triggered by the initiator, generating a long DNA polymer. Under optimum conditions, the aptasensor exhibited a log-linear range from 0.001 to 100 nM of chloramphenicol and a detection limit of 0.3 pM. Additionally, the designed biosensing platform was applied to determine chloramphenicol in milk and lake water with high accuracy. The current approach provides a new avenue to develop sensitive aptasensors with the assistance of binding mechanism between aptamer and target compounds. [Figure not available: see fulltext.]

Original languageEnglish
Article number505
JournalMicrochimica Acta
Issue number9
Publication statusPublished - 1 Sept 2020
Externally publishedYes


  • Aptasensor
  • Binding mechanism
  • Chloramphenicol
  • Exonuclease I
  • Hybridization chain reaction

ASJC Scopus subject areas

  • Analytical Chemistry


Dive into the research topics of 'Structure-switching fluorescence aptasensor for sensitive detection of chloramphenicol'. Together they form a unique fingerprint.

Cite this