Real-time glutamate measurements in the putamen of awake rhesus monkeys using an enzyme-based human microelectrode array prototype

J Neurosci Methods. 2010 Jan 15;185(2):264-72. doi: 10.1016/j.jneumeth.2009.10.008. Epub 2009 Oct 20.


Commonly used for research studies in the central nervous system, microdialysis has revealed a link between dysregulation of the excitatory neurotransmitter glutamate and ischemia and seizure, however limitations like slow temporal resolution have stalled the advancement of microdialysis as a diagnostic tool. We have developed and extensively characterized an enzyme-based microelectrode array technology for second-by-second in vivo amperometric measurements of glutamate in the mammalian CNS. The current studies demonstrated the ability of a human microelectrode array prototype (Spencer-Gerhardt-2 (SG-2)) to measure tonic and phasic glutamate neurotransmission in the putamen of unanesthetized non-human primates. We also showed that the SG-2 remains functional following sterilization. Ability to monitor dynamic changes in glutamate in real-time may assist the development of clinical algorithms to potentially alert care-providers prior to onset of overt ischemia or seizure, or provide neurosurgeons with second-by-second measurements of rapid changes in extracellular glutamate which could help guide surgical procedures or aid in interventional strategies.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Electrochemistry / instrumentation*
  • Electrochemistry / methods*
  • Enzymes
  • Female
  • Glutamic Acid / metabolism*
  • Humans
  • Macaca mulatta
  • Magnetic Resonance Imaging / methods
  • Microdialysis / methods
  • Microelectrodes*
  • Putamen / metabolism*
  • Wakefulness*


  • Enzymes
  • Glutamic Acid