Release Date:  December 1, 1999

NOTICE:  NS-00-003	



The National Institute of Neurological Disorders and Stroke (NINDS), is 
seeking to identify sources that are interested and have the potential 
capability to study biomaterials for the CNS with a long-term goal of 
rationally designing microelectrode surfaces to promote integration of 
microelectrodes within the CNS.  The information requested below will 
aid in planning and developing a possible solicitation for this 
potential initiative.  It is our opinion that the most suitable target 
audience to respond to this inquiry would be organizations engaged in 
or familiar with similar research.


Biomaterials that are implanted into the central nervous system, such 
as the microscopic electrode shafts of neural prostheses, should 
interact with neural and other tissues on a cellular and molecular 
level.  Two differences between the implant and the neural tissue that 
hinder this interaction are differences in stiffness and differences in 
surface chemistry.  For example, silicon microelectrodes have an 
elastic modulus of around 100 gigaPascals whereas the stiffness of 
neural tissue is on the order of 0.1 megapascals.  This million fold 
difference in stiffness results in significant differential movement in 
response to external stress.  The imbalance probably causes greater 
problems in large brained animals where stress loads are larger and may 
account for the greater difficulty that has been encountered in chronic 
recording from larger brained animals.

An implanted surface must not move with respect to the neural tissue it 
is making connections with.  In addition, the surface of an implant 
must be recognized biochemically by the neural tissue as a surface that 
is appropriate for contact.  This interaction between implanted 
microelectrode and neural tissue must be understood and controlled.  
Controlling the interaction requires an understanding of how cells, 
including neurons and glia, and extracellular matrix respond to the 
surface chemistry of the implant and knowledge about leachable 
substances of implanted biomaterials.  Microelectrodes offer the 
possibility of controlled stimulation of smaller volumes of neural 
tissue – on the order of one thousand to one hundred thousand times 
smaller than those used today – provided that the surface interaction 
between the microelectrode and the neural tissue is controlled.

This Request for Information (RFI) is for information and planning 
purposes only and shall not be construed as a solicitation or as an 
obligation on the part of the Government.  The Government does not 
intend to award a contract on the basis of responses nor otherwise pay 
for the preparation of any information submitted or the Government’s 
use of such information.  Acknowledgement of receipt of responses will 
not be made, nor will respondents be notified of the Government’s 
evaluation of the information received.  However, should such a 
requirement materialize, no basis for claims against the Government 
shall arise as a result of a response to this request for information 
or the Government’s use of such information as either part of our 
evaluation process or in developing specifications for any subsequent 
requirement.  Responses will be held in a confidential manner.  Any 
proprietary information should be so marked.

All respondents are asked to indicate the type and size of your 
business organization, e.g., Large Business, Small Business, Small 
Disadvantaged Business, Women-Owned Business, 8 (a), Historically Black 
College or University/Minority Institution (HBCU/MI), educational 
institution, profit/non-profit hospital, or other nonprofit 

Responses should be identified with NIH-NINDS-RFI-00-03, and are due by 
December 13, 1999.  Please submit three copies of your response to the 
attention of: Desiree Y. Wheeler, Contract Specialist, Contracts 
Management Branch, National Institute of Neurological Disorders and 
Stroke, NIH, 6001 Executive Boulevard, Room 3287, MSC 9531, Bethesda, 
Maryland  20892-9531.  Facsimile responses will also be accepted.  E-
mail responses, sent to, will also be accepted. 

Return to Volume Index

Return to NIH Guide Main Index

Office of Extramural Research (OER) - Home Page Office of Extramural
Research (OER)
  National Institutes of Health (NIH) - Home Page National Institutes of Health (NIH)
9000 Rockville Pike
Bethesda, Maryland 20892
  Department of Health and Human Services (HHS) - Home Page Department of Health
and Human Services (HHS) - Government Made Easy

Note: For help accessing PDF, RTF, MS Word, Excel, PowerPoint, Audio or Video files, see Help Downloading Files.