Whole-Cell Biosensing by Siderophore-Based Molecular Recognition and Localized Surface Plasmon Resonance

Article

Abstract

Selective whole-cell Acinetobacter baumannii detection using a biotinylated siderophore–Fe( iii ) complex in a localized surface plasmon resonance biosensing platform. A siderophore-based active bacterial pull-down strategy was integrated in a localized surface plasmon resonance (LSPR) sensing platform and subsequently tested by detecting whole-cell Acinetobacter baumannii . The LSPR-based whole-cell sensing approach was previously demonstrated with aptamer-based molecular recognition motifs, and here it is extended to the powerful siderophore system, which exploits the natural bacterial need to sequester Fe( iii ). Specifically, a biscatecholate–monohydroxamate mixed ligand siderophore linked to a biotin via three polyethylene glycol repeating units was synthesized and immobilized on Au trigonal nanoprisms of an LSPR sensor. The resulting surface-confined biotinylated siderophore subsequently chelated Fe( iii ), forming a siderophore–Fe( iii ) complex which was shown to be competent to recognize A. baumannii . Target bacteria were captured and then detected by measuring wavelength shifts in the LSPR extinction spectrum. This siderophore pull-down LSPR biosensor approach is rapid (≤3 h detection) and sensitive – with a limit of detection (LOD) of 80 bacterial cells and a linear wavelength shift over the range 4 × 10 2 to 4 × 10 6 cfu mL −1 . As intended by design, the siderophore-based biosensor was selective for A. baumannii over Pseudomonas aeruginosa , Escherichia coli , and Bacillus cereus , and was stable in ambient conditions for up to 2 weeks.

Attributes

Attribute NameValues
Creator
  • Jiayun Hu

  • Manuka Ghosh

  • Marvin Miller

  • Paul Bohn

Journal or Work Title
  • Analytical Methods

Volume
  • 11

First Page
  • 296

Last Page
  • 302

ISSN
  • 17599679

Publication Date
  • 2019-01

Subject
  • SEM

Publisher
  • The Royal Society of Chemistry

Date Created
  • 2019-08-26

Language
  • English

Departments and Units
Record Visibility and Access Public
Content License
  • All rights reserved

Digital Object Identifier

doi:10.1039/c8ay02180e

This DOI is the best way to cite this article.