Amino Acids

, Volume 47, Issue 7, pp 1379–1388 | Cite as

Chemically functionalized single-walled carbon nanotubes enhance the glutamate uptake characteristics of mouse cortical astrocytes

  • Manoj K. Gottipati
  • Elena Bekyarova
  • Robert C. Haddon
  • Vladimir ParpuraEmail author
Original Article


Using a radioactive glutamate uptake assay and immunolabeling, we report that single-walled carbon nanotubes, chemically functionalized with polyethylene glycol (SWCNT-PEG), delivered as a colloidal solute, cause an increase in the uptake of extracellular glutamate by astrocytes and an increase in the immunoreactivity of the glutamate transporter GLAST on their cell surface, which is likely a consequence of an increase in the immunoreactivity of glial fibrillary acidic protein. Additional corollary is that astrocytes exposed to SWCNT-PEG became larger and stellate, morphological characteristics of maturation and heightened activity of these glial cells. These results imply that SWCNT-PEG could potentially be used as a viable candidate for neural prosthesis applications, perhaps to alleviate the death toll of neurons due to glutamate excitotoxicity, a pathological process observed in brain and spinal cord injuries.


Carbon nanotubes Astrocytes Glial fibrillary acidic protein Glutamate excitotoxicity 



Carbon nanotube


Excitatory amino acid transporter


Glial fibrillary acidic protein


l-Glutamate/l-aspartate transporter


Glial l-glutamate transporter


Indirect immunocytochemistry




Polyethylene glycol


Rho-associated protein kinase


Single-walled carbon nanotube


dl-Threo-β-benzyloxyaspartic acid



We thank Stephanie M. Robert and Dr. Harald Sontheimer, University of Alabama at Birmingham, for their help with the glutamate uptake study and Dr. Vladimir Grubišić for his constructive comments on a previous version of this manuscript. V. Parpura acknowledges the support of this work by National Institutes of Health (The Eunice Kennedy Shriver National Institute of Child Health and Human Development award HD078678).

Conflict of interest

The authors declare that they have no conflict of interest.

Ethical standard

All applicable international, national and/or institutional guidelines for the care and use of animals were followed. All procedures performed in studies involving animals were in accordance with the ethical standards of the institution or practice at which the studies were conducted.

Supplementary material

726_2015_1970_MOESM1_ESM.docx (401 kb)
Supplementary material 1 (DOCX 401 kb)


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Copyright information

© Springer-Verlag Wien 2015

Authors and Affiliations

  • Manoj K. Gottipati
    • 1
  • Elena Bekyarova
    • 2
    • 3
  • Robert C. Haddon
    • 4
    • 5
  • Vladimir Parpura
    • 1
    • 6
    Email author
  1. 1.Department of Neurobiology and Department of Biomedical EngineeringUniversity of Alabama at BirminghamBirminghamUSA
  2. 2.Department of Chemistry and Department of Chemical Engineering, Center for Nanoscale Science and EngineeringUniversity of CaliforniaRiversideUSA
  3. 3.Carbon Solutions, Inc.RiversideUSA
  4. 4.Department of Chemistry and Department of Chemical Engineering, Center for Nanoscale Science and EngineeringUniversity of CaliforniaRiversideUSA
  5. 5.Department of PhysicsKing Abdulaziz UniversityJeddahSaudi Arabia
  6. 6.Department of BiotechnologyUniversity of RijekaRijekaCroatia

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