Highly sensitive label-free in vitro detection of aflatoxin B1 in an aptamer assay using optical planar waveguide operating as a polarization interferometer

Ali Al-Jawdah, Alexei Nabok, Hisham Abu-Ali, Gaelle Catanante, Jean Louis Marty, Andras Szekacs

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

This work reports on further development of an optical biosensor for the in vitro detection of mycotoxins (in particular, aflatoxin B1) using a highly sensitive planar waveguide transducer in combination with a highly specific aptamer bioreceptor. This sensor is built on a SiO2–Si3N4–SiO2 optical planar waveguide (OPW) operating as a polarization interferometer (PI), which detects a phase shift between p- and s-components of polarized light propagating through the waveguide caused by the molecular adsorption. The refractive index sensitivity (RIS) of the recently upgraded PI experimental setup has been improved and reached values of around 9600 rad per refractive index unity (RIU), the highest RIS values reported, which enables the detection of low molecular weight analytes such as mycotoxins in very low concentrations. The biosensing tests yielded remarkable results for the detection of aflatoxin B1 in a wide range of concentrations from 1 pg/mL to 1 μg/mL in direct assay with specific DNA-based aptamers. [Figure not available: see fulltext.].

Original languageEnglish
Pages (from-to)7717-7724
Number of pages8
JournalAnalytical and Bioanalytical Chemistry
Volume411
Issue number29
DOIs
Publication statusPublished - Nov 1 2019

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Keywords

  • Aflatoxin B1
  • Aptamer
  • Optical planar waveguide
  • Polarization interferometer
  • Refractive index sensitivity

ASJC Scopus subject areas

  • Analytical Chemistry
  • Biochemistry

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