An innovative dual recognition aptasensor for specific detection of Staphylococcus aureus based on Au/Fe3O4 binary hybrid

Sci Rep. 2022 Jul 22;12(1):12502. doi: 10.1038/s41598-022-15637-1.

Abstract

Pathogenic bacteria cause disease outbreaks and threaten human health, prompting the research on advanced detection assays. Herein, we developed a selective molecular imprinted aptasensor for sensitive and prompt quantitation of Staphylococcus aureus (S. aureus) bacteria. The aptasensor was constructed by immobilization of aptamer on gold nanoparticles modified magnetic nanoparticles (apt-AuNPs@ Fe3O4). A functional monomer (o-phenylenediamine, o-phen) was electro-polymerized on the surface of the as-synthesized nanocomposite in the presence of a template (S. aureus). After removing S. aureus, the formed imprinted sites were available to extract pathogenic bacteria from complicated matrices. The surface morphology of the as-fabricated nanocomposites was characterized using different spectroscopic and electrochemical methods. Moreover, we thoroughly evaluated factors affecting the synthesis and determination procedures. The molecular imprinted aptasensor exhibited a wide linear range of 101-107 CFU mL-1 with a Limit of Detection, LOD (signal to noise = 3) of 1 CFU mL-1. The aptasensor detected S. aureus in milk, conduit water, and apple juice samples with good recoveries % and satisfactory relative standard deviations (RSDs %) values.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aptamers, Nucleotide* / chemistry
  • Biosensing Techniques* / methods
  • Electrochemical Techniques / methods
  • Gold / chemistry
  • Humans
  • Limit of Detection
  • Metal Nanoparticles* / chemistry
  • Staphylococcal Infections* / diagnosis
  • Staphylococcus aureus

Substances

  • Aptamers, Nucleotide
  • Gold