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Article: 1956 of alt.cyberpunk.tech
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From: j_wilson@access.digex.net (John M. Wilson)
Newsgroups: alt.cyberpunk.tech
Subject: BIOCHIP TECHNOLOGY UPDATE - SOURCES, REFERENCES & TEXT
Date: 25 Jun 1993 17:22:01 -0400
Organization: Express Access Online Communications, Greenbelt, MD USA
Lines: 400
Message-ID: <j_wilson.741043297@access>
NNTP-Posting-Host: access.digex.net
Summary: a current listing of biochip technology for the cyberpunk
Keywords: BIOCHIP CYBERPUNK NANOTECHNOLOGY BACTERIORHODOPSIN
Status: RO

 
TO:    CyberPunks
 
FROM:  J_Wilson@ACM.ORG
 
RE:    Biochip Technology
 
DATE:  24-JUN-1993
 
       The purpose of this memorandum is to document the current status of 
       biochip technology and to promote serious discussion of the topic.
 
       Almost anyone who has read the stories of George Alec Effinger, William 
       Gibson or W.T. Quick, knows that one of the mainstays of the cyberpunk 
       novel is the "biochip", an organic microprocessor which enables the user 
       to interface with computer systems and other biochip users.
 
       In the context of the cyberpunk novel the "biochip" provides perceptual 
       abilities by translating complex datastructures into the architecture of 
       cyberspace and motor skills by converting motions into intersystem 
       commands to manipulate those datastructures.
 
       Current biochip research appears to fall into two classes, the first is 
       in the category of molecular electronics where organic molecules are 
       used to create nanocircuit elements for the purpose of further reducing 
       chip sizes, the second is in the realm of prosthetics where an implanted 
       organic transducer can relay signals to and from external sources 
       without the eventual rejection posed by conventional techniques.
 
       What follows is information to help establish answers to two questions;
 
       1) When will biochip technology become available to the public?
 
       2) When it becomes available, will anyone really want it?
 
       The appended information will fall into roughly three categories, 
       sources, references and full text. These will be updated as new 
       information becomes available.
 
       Individuals who wish to add to the information contained in this file 
       are encouraged to contact J_Wilson@ACM.ORG. Contributors will be put on 
       a group mailing list for updates as they are posted.
 
***********************************************************************
       SOURCES - listed alphabetically                                 
***********************************************************************
 
The BIOSIS database on DIALOG.
 
       While this is an excellent source of information, it is also quite 
expensive. Some colleges will perform specific datasearches for students and 
staff at no charge.
 
 
C.A.R.L. The Colorado Alliance of Research Libraries.
 
       Many public libraries have public terminals allowing access to 
newspaper, periodical and library databases around the country. There is no 
user fee or connect charge and many sources have full text available online. 
Those sources that are not online can be obatined through interlibrary loan or 
faxed to you for a fee. If you prefer to do research at home, ask the reference 
librarian for the telephone number and dial in direct.
 
 
***********************************************************************
        REFERENCES - to be categorized later                           
***********************************************************************
 
 
 
FORMAT:       book
LOCATION:     TSCO   QH324.U56
CONTROL NBR:  40850471
TITLE:        University of Maryland Task Force on High
              Technology/Biotechnology report.
PUBLISHER:    The Task Force.
DATE:         1983.
SUBJECT:      Bionics.
SUBJECT:      High technology.
 
 
 
AUTHOR: Erickson, Deborah
TITLE:  Not biochips? There may yet be computers made with organic
        molecules.
        illustration chart
 
        p136 (3)
        Scientific American
        Nov 1990  v263 n5
 
DESCRIPTORS:    Molecular electronics_Research 
                Organic compounds_Electric properties
 
FILM NUMBER:    56M 2157
 
 
 
AUTHOR: Lamb, John
TITLE:  Biochips with everything, (molecular electronics)
        illustration photograph
 
        p133 (1)
        Management Today
        April 1988
 
 
 
AUTHOR: Pietrantoni, Michael
TITLE:  The computer is alive. Building the bio-chip
        
        p88 (3)
        USA Today
        July  1990  v119  n2542
 
DESCRIPTORS:    Semiconductors chips_research
                Computers_innovations
 
 
----------------------------------------------------U of Maryland System------- 
AUTHOR(s):       International School of Pure and Applied Biostructure  (9th
                   :  1988 :  Erice, Italy)                                   
TITLE(s):        Towards the biochip :  9th Course of the International
                   School of Pure and Applied Biostructure, Erice, Italy,
                   November 27-December 4, 1988 /  edited by C. Nicolini.     
 
                 Singapore ;  Teaneck, N.J. :  World Scientific,  c1990.  
                 vi, 231 p. :  ill. ;  23 cm.  
                 Includes bibliographical references.  
 
 
OTHER ENTRIES:   Integrated circuits--Congresses.  
                 Biotechnology--Congresses.  
                 Neural computers--Congresses.  
                 Nicolini, Claudio A.  
                 Biochip.  
 
 
Owners: UMCP 
 
UMCP    ENGIN  BKSTKS    STATUS: Due: 02/01/94 CALL #: TK7874.I5922 1988  
 
----1 of 2------------------------------------------U of Maryland System------- 
----------------------------------------------------U of Maryland System------- 
TITLE(s):        Advanced computers :  parallel and biochip processors/  by
                   Norman W. Lord ... [et al.]                                
 
                 Ann Arbor, Mich. :  Ann Arbor Science, Butterworth Group, 
                   c1983.                                                     
                 xii, 155 p. :  ill. ;  24 cm.  
                 Includes bibliographies and index.  
 
OTHER ENTRIES:   Computers.  
                 Parallel processing (Electronic computers)  
                 Molecular electronics.  
                 Lord, Norman W.  
                 Parallel and biochip processors.  
 
 
Owners: UMBC UMCP 
 
UMBC    STACKS           STATUS: Not checked out CALL #: QA76.A38  
 
CALL #: QA76.A38  
 
----2 of 2------------------------------------------U of Maryland System-------
----------------------------------------------------U of Maryland System-------
TITLE(s):        Cyborg worlds :  the military information society /  edited
                   by Les Levidow and Kevin Robins.                           
 
                 London :  Free Association Books,  1989.  
                 186 p. :  ill. ;  24 cm.  
                 Includes bibliographical references and index.  
 
OTHER ENTRIES:   Sociology, Military.  
                 Military art and science--Data processing--Psychological
                   aspects.                                                   
                 Electronic data processing--Psychological aspects.  
                 Computers and civilization.  
 
                 Cybernetics.  
                 Levidow, Les.  
                 Robins, Kevin.  
 
 
Owners: UMCP 
 
UMCP    ENGIN  BKSTKS    STATUS: Not checked out CALL #: U21.5.C93 1989  
 
----1 of 8-----------------------------------------U of Maryland System--------
 
----------------------------------------------------UnCover-------------------- 
AUTHOR(s):       Williams III., Gurney  
TITLE(s):        Forum.  
Summary:         Biochip implants help students organize their thoughts:
                   What other changes in education can we expect to see over
                   the next 50 years?                                         
 
           In:   Omni.  
                 APR 01 1990 v 12 n 7  
         Page:   16  
 
OWNERS: AUR CSU CU  DPL DU  UNC                                                
                         ISSUE STATUS: Published             
---1 of 1-------------------------------------------UnCover--------------------
 
 
 
***********************************************************************
        FULL TEXT ARTICLES                                             
***********************************************************************
 
 
----------------------------------------------------Magazine Index & ASAP------ 
AUTHOR(s):       Erickson, Deborah 
TITLE(s):        Not biochips? There may yet be computers made with organic
                   molecules.                                                 
                  illustration chart   
 
                 p136(3) 
                 Scientific American 
                 Nov  1990  v263  n5   
 
DESCRIPTORS:     Molecular electronics_Research 
                 Organic compounds_Electric properties 
                 Nanotechnology_Research 
 
FILM NUMBER:     56M 2157 
 
----1 of 2-----On-line text or FAX available ------Magazine Index & ASAP-------
 
 
 
     Some wild talk was going around in 1983 that the same kinds of genetic    
   engineering techniques enabling microorganisms to produce drugs would       
   also let them churn out computers.  The organisms would self-assemble       
   "biochips"--complex clusters of organic molecules that would function as    
   integrated circuitry but be thousands of times smaller than                 
   conventional components.  Or so the story went.  Some investors bit hard    
   before the scheme--and the company promoting it--was debunked by a          
   federal scientific inquiry.                                                 
 
     The ridicule that followed continues to haunt a small group of serious    
   researchers, who believe that organic molecules can indeed be made to       
   work as submicroscopic computer elements.  Please, they plead, don't use    
   the word "biochip" to describe their work.  Their challenge is to build     
   organic molecules that can repeatedly switch from conductive to             
   nonconductive states and back again, just like conventional electronic      
   components made of semiconductors such as silicon.                          
 
     The research, which parallels perennial efforts to shrink the size of     
   semiconductor components, remains largely theoretical.  It will be years    
   before any molecular electronics devices are commercialized--if ever.       
   But scientists are reporting tantalizing early successes.  Some skeptics    
   are beginning to wonder if there might be something to the idea after       
   all.  "People are excited about pushing chemistry to new frontiers,"        
   says Robert M. Metzger, a physical chemist at the University of Alabama     
   at Tuscaloosa.  He notes, "The physicists are encouraging us, and the       
   engineers are at least not laughing at us any more."                        
 
     This summer, organic chemist James M. Tour of the University of South     
   Carolina at Columbia announced that he had synthesized a section of a       
   molecule that might function as an electronic switch.  His blueprint was    
   proposed by IBM researcher Ari Aviram in 1988.  Aviram, who first began     
   musing about molecular computer parts in the early 1970s, envisioned        
   large organic molecules that could give and accept electrons and so         
   carry current.                                                              
 
     The model could pass a single electron between two molecular              
   chains--enough to make a switch, if the electron's movement could be        
   controlled.  The chain donating the electron would become a conductor,      
   and the one receiving it would become an insulator.  The chains were        
   joined with a bridge for the electron to cross.                             
 
     To keep the electron from jumping at will, Aviram twisted the bridge      
   at a 90-degree angle so that the arms of the molecule would look like a     
   plus sign if viewed from above.  This way, the chains would be separated    
   from each other, and the electron could move from one to the other only     
   when forced to, by voltage applied through an electrode abutting the        
   bridge.  Current would move through the chain that gave up the electron     
   into electrodes attached at either end.                                     
 
     So far Tour and two graduate students have made a couple of versions      
   of these twisted bridges.  In one, the chains are based on a conductive     
   polymer called polythiophene, which has a backbone of sulfur molecules.     
   "We're building the chains separately, then we'll slap the pieces           
   together," he says.  Tour says his approach to constructing large           
   molecules to order is borrowed from pharmaceutical manufacturing, but it    
 
   has not been used widely by materials scientists.                           
 
     Tour acknowledges that the molecule he has built is just the              
   beginning.  After all the chemical tricks and hard labor, the molecular     
   chain is still only 23 angstroms long, less than half the size Aviram       
   described.  "Chemists shy away from making molecules that big," Aviram      
   says.  "It's a very laborious undertaking."                                 
 
     Unfortunately, a molecule that could connect to circuit lines on          
   conventional semiconductor chips would have to be far bigger than that.     
   And such connections are necessary before a billion or so molecules         
   could be wired together into working computer components.  With current     
   commercial methods for etching conductive paths on semiconductor chips,     
   the distance between individual circuit lines is typically 8,000            
   angstroms.  Even the most dense techniques of electron-beam patterning      
   bring the wires no closer than 150 angstroms.  To bridge these minute       
   conductors, a molecule would still have to be three times the size of       
   the one Aviram postulated.  But Tour is optimistic that he can build        
   much larger molecules.  "Now it's just a matter of hooking more             
   thiophenes into the chains," he says.                                       
 
     Aviram and other proponents of the new electronics figure that by the     
   time organic molecules are ready to roll out, circuit-pattern distances     
   will not be so vast.  Even then, the molecules would somehow have to be     
   connected to the conductive "wiring."  One possible solution is             
   designing molecules that contain a specific atom, or collections of         
   atoms, known to have affinity for a particular substance.                   
 
     "These functional groups will be important to wiring up molecules,"       
   declares Mark S. Wrighton, a chemist at the Massachusetts Institute of      
   Technology.  He offers an example of how the approach could simplify        
   manufacturing: Because sulfur-containing molecules stick to gold, and       
   carboxylic groups bind to aluminum oxide, an array of wires containing      
   those metals could be dipped into a solution of the organic molecules       
   and emerge with conductive connections exactly where they ought to be.      
 
     Others working in molecular electronics believe single molecules may      
   present too many problems to be practical.  "How do you connect a single    
   molecule?" Metzger asks.  He is working instead on devices built from       
   films a molecule thick.  Carefully patterned layers stacked on top of       
   one another could make vertical as well as horizontal connections,          
   obviating bulky wires and increasing the circuit density.                   
 
     Metzger explains that the trick is to design directionality into the      
   molecules--to give them, for instance, greasy tails so they move away       
   from water and line up facing the same way.  But he still has not           
   figured out how to carve patterns in a layer.                               
 
     The delicacy of one-molecule-thick films makes them vulnerable to         
   pinholes and other defects, but researchers who favor the approach say      
   such devices will still be more reliable than single molecules.  To add     
   stability to films, some scientists are binding the molecules to polymer    
   substrates.                                                                 
 
     Metzger and his collaborators have made a film five by 10 inches and      
 
   are testing to confirm that it conducts current in one direction.  The      
   next step will be to control manufacture to make the working size           
   smaller.  "Within the next two years, somebody will know for sure           
   whether films work.  From that to a workable device, it'll be maybe 10      
   years," Metzger predicts.                                                   
 
     Even Aviram acknowledges that single organic molecules probably will      
   not be reliable enough to use alone.  "No one disputes there will be a      
   need for redundancy," he says.  Exactly how much redundancy will be         
   necessary has to be determined experimentally.  Because fully functional    
   molecules have not yet been made, the matter is mostly intuitive at         
   present.  Critics point out that the more molecules get piled up for        
   safety's sake, the closer organic systems will come to the size of          
   conventional devices.  Supporters note that a model of individual           
   molecules used for data processing and storage already exists in            
   nature--in the form of DNA.                                                 
 
     Some researchers, in fact, are looking to nature for molecules that       
   switch naturally.  At the Syracuse University Center for Molecular          
   Electronics, Robert R. Birge is using bacterial rhodopsin as a switch       
   for a high-speed RAM (random-access memory).  A pulse of laser light        
   causes the chemical to switch from one form to another.  The substance,     
   similar to pigment found in the retina of the human eye, comes from a       
   bacteria found in salt marshes.  "It's a very old organism--the only one    
   I know of that can transfer from breathing to photosynthesis," he           
   notes.                                                                      
 
     Copper's well-known friendliness toward electricity is earning the        
   element a place in some molecular electronics research.  A group led by     
   Richard S. Potember of the Johns Hopkins University Applied Physics         
   Laboratory is adding copper to a thin film of an organic molecule called    
   tetracyanoquinodimethane (TCNQ).  Pulses of high voltage or laser light     
   cause the copper atoms to bind and unbind from TCNQ, switching the film     
   from conducting to nonconducting.  A similar TCNQ film is being             
   developed at Japan's National Chemical Laboratory for Industry, where a     
   group headed by Hiroaki Tachibana is using heat to flip the switch.         
 
     Predictably, few molecular electronics researchers are guessing how       
   long it will be until some of their devices become commercial realities.    
 
     But all are encouraged by the speed at which developing                   
   technologies--particularly scanning tunneling electron microscopes--are     
   allowing them to observe and construct materials on a molecular level.      
   At the same time, manufacturing techniques for structures approaching       
   the size of large molecules are getting better.  "Molecular electronics     
   is a distant goal," Aviram concedes.  But he notes, "There are a lot of     
   beautiful scientific milestones until then."                                
 
 
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