Affordable Access

Publisher Website

Picomolar glyphosate sensitivity of an optical particle-based sensor utilizing biomimetic interaction principles.

  • Rettke, David1
  • Döring, Julia2
  • Martin, Steve1
  • Venus, Tom3
  • Estrela-Lopis, Irina3
  • Schmidt, Stephan4
  • Ostermann, Kai2
  • Pompe, Tilo5
  • 1 Institute of Biochemistry, Leipzig University, Johannisallee 21-23, 04103, Leipzig, Germany. , (Germany)
  • 2 Institute of Genetics, Technische Universität Dresden, Zellescher Weg 20b, 01217, Dresden, Germany. , (Germany)
  • 3 Institute of Medical Physics and Biophysics, Leipzig University, Härtelstraße 16-18, 04107, Leipzig, Germany. , (Germany)
  • 4 Institute of Organic Chemistry and Macromolecular Chemistry, Heinrich Heine Universität Düsseldorf, Universitätsstraße 1, 40225, Düsseldorf, Germany. , (Germany)
  • 5 Institute of Biochemistry, Leipzig University, Johannisallee 21-23, 04103, Leipzig, Germany. Electronic address: [email protected] , (Germany)
Published Article
Biosensors & bioelectronics
Publication Date
May 11, 2020
DOI: 10.1016/j.bios.2020.112262
PMID: 32510337


The continually growing use of glyphosate and its critically discussed health and biodiversity risks ask for fast, low cost, on-site sensing technologies for food and water. To address this problem, we designed a highly sensitive sensor built on the remarkably specific recognition of glyphosate by its physiological target enzyme 5-enolpyruvyl-shikimate-3-phosphate synthase (EPSPs). This principle is implemented in an interferometric sensor by using the recently established soft colloidal probe (SCP) technique. EPSPs was site-specifically immobilized on a transparent surface utilizing the self-assembling properties of circadian clock gene 2 hydrophobin chimera and homogeneity of the layer was evidenced by atomic force microscopy. Exposure of the enzyme decorated biochip to glyphosate containing samples causes formation of enzyme-analyte complexes and a competitive loss of available binding sites for glyphosate-functionalized poly(ethylene glycol) SCPs. Functionalization of the SCPs with different types of linker molecules and glyphosate was assessed employing confocal laser scanning microscopy as well as confocal Raman microspectroscopy. Overall, reflection interference contrast microscopy analysis of SCP-biochip interactions revealed a strong influence of linker length and glyphosate coupling position on the sensitivity of the sensor. In employing a combination of pentaglycine linker and tethering glyphosate via its secondary amino group, concentrations in aqueous solutions down to 100 pM could be measured by the differential adhesion between SCP and biochip surface, supported by automated image analysis algorithms. This sensing concept could even prove its exceptional pM sensitivity in combination with a superior discrimination against structurally related compounds. Copyright © 2020 Elsevier B.V. All rights reserved.

Report this publication


Seen <100 times