Design of a mediator-free, non-enzymatic electrochemical biosensor for glutamate detection

Elnaz Zeynaloo, Yu Ping Yang, Emre Dikici, Ralf Landgraf, Leonidas G. Bachas, Sylvia Daunert

Research output: Contribution to journalArticlepeer-review

8 Scopus citations


A mediator-free, non-enzymatic electrochemical biosensor was constructed by covalent immobilization of a genetically engineered periplasmic glutamate binding protein onto gold nanoparticle-modified, screen-printed carbon electrodes (GluBP/AuNP/SPCE) for the purpose of direct measurement of glutamate levels. Glutamate serves as the predominant excitatory neurotransmitter in the central nervous system. As high levels of glutamate are an indicator of many neurologic disorders, there is a need for advancements in glutamate detection technologies. The biosensor was evaluated for glutamate detection by cyclic voltammetry. Binding of glutamate to the immobilized glutamate binding protein results in a conformational change of the latter that alters the microenvironment on the surface of the sensor, which is manifested as a change in signal. Dose–response plots correlating the electrochemical signal to glutamate concentration revealed a detection limit of 0.15 μM with a linear range of 0.1-0.8 μM. Selectivity studies confirmed a strong preferential response of the biosensor for glutamate against common interfering compounds.

Original languageEnglish (US)
Article number102305
JournalNanomedicine: Nanotechnology, Biology, and Medicine
StatePublished - Jan 2021


  • Glutamate biosensor
  • Gold nanoparticle
  • Non-enzymatic
  • Periplasmic binding protein
  • Screen-printed carbon electrode

ASJC Scopus subject areas

  • Bioengineering
  • Medicine (miscellaneous)
  • Molecular Medicine
  • Biomedical Engineering
  • Materials Science(all)
  • Pharmaceutical Science


Dive into the research topics of 'Design of a mediator-free, non-enzymatic electrochemical biosensor for glutamate detection'. Together they form a unique fingerprint.

Cite this