Catch up on stories from the past week (and beyond) at the Slashdot story archive

 


Forgot your password?
Close
typodupeerror
×

Cocaine Biosensor 180

Posted by ScuttleMonkey from the electric-sensor-land dept.
Aaron Rowe writes "The MIT Technology review reports that a lab at UC Santa Barbara has created a biosensor by attaching a special type of DNA called an aptamer to a gold electrode. When cocaine is present, the aptamer tightly hugs a cocaine molecule and leans over so that a metal tag can touch the gold surface. This causes a spike in a plot of current versus voltage when the electrode is attached to a machine called a cyclic voltmeter."
This discussion has been archived. No new comments can be posted.

Cocaine Biosensor More

Cocaine Biosensor

Comments Filter:

  • Gold? (Score:4, Interesting)

    by dada21 ( 163177 ) * <adam.dada@gmail.com> on Monday March 13, 2006 @11:37PM (#14913167) Homepage Journal
    I'm a known gold bug [blogspot.com] and I've been very interested in the industrial applications of gold (partially to gauge demand issues for future supply). In recent months I've found gold being useful for medicine (possibly as a cancer detector most recently). Now it seems it is useful in finding drugs (although I'm sure this would be only for a police purpose, in a free market the same device might be useful in finding the best drugs).

    What are the reasons for gold being used in these situations? I'm very familiar with gold's uniqueness, but it surprises me that it is becoming such a popular metal again -- even beyond the computer and audio industry. Is it really unique for these applications, or is it just a great way for the manufacturers to pad their bottom lines?

    • Re:Gold? (Score:5, Informative)

      by rubycodez ( 864176 ) on Monday March 13, 2006 @11:47PM (#14913227)
      Gold being soft means less force is required to make a good low-resistance electrical contact. So gold is the king of conductors for contact applications. Add to that the fact that it doesn't corrode or oxidize under normal conditions, it beats the two better conductors (at room temperature), silver and copper.
      • I'm aware of those aspects, and I've always assumed that's the reason for use in medicine, but I was wondering if there were other reasons for it beyond the electrical and anti-corrosive properties.

        One thing though -- I was often told that gold is not as good of a conductor as copper, but the reason it is considered better is strictly because copper corrodes so quickly, and can then reduce the effectiveness of copper over gold.
        • hurray, you give me a chance to dig out my thousands of pages long CRC Handbook of Chemistry and Physics (63rd Edition). The resistivity (microhm-cm) of silver, copper, gold, aluminum at 20 degrees C are (drum roll): 1.586, 1.678, 2.24, 2.6548. So that's not true about copper.
          • Uh, you mean it IS true.

            Over a given run of wire, you'll get less of a voltage drop with copper.
            • right, somehow I read parent that gold alleged better conductor than copper, which it isn't. Noticed sodium was 4.7 but measured at 0 degrees C, the guy that tried it at room temp they call "stumpy", hehehe
          • I'm too lazy to do the research but it has something to do with the number of electrons in the outer circle of the atom.

            If I remeber right Silver only has 1 in the outer circle thus can pass the most electrons from atom to atom.

            I state this completely out of my arse and relying on 15 year old high school education so someone please come by and correct me. I think I'm pretty close though from what I remeber.

    • Re: Gold? (Score:5, Funny)

      by Black Parrot ( 19622 ) on Monday March 13, 2006 @11:47PM (#14913228)
      > I'm a known gold bug and I've been very interested in the industrial applications of gold

      I'm interested in economic applications, but unfortunately I don't have as much as I need for some of the experiments I'd like to try.
      • With as much yay being distributed around the UCSB campus, it's not surprise the abundance of it caused some students to include it into their next lab project!

    • Re:Gold? (Score:2, Informative)

      by Anonymous Coward
      I actually came across this paper in JACS a few days ago and a tiny amount of gold is used in the electrode, primarily because it makes the chemistry of attaching the aptamer to the electrode easy. Basically, aside from being easy to tether stuff to, gold doesn't play an integral role in the analysis.
      • Thanks, that's the answer I was looking for. The common answer -- conductivity -- is knowledgeable to all and I appreciate those comments, but I was wondering why gold over others and you pointed me in the direction I needed to head in with my research. Much appreciated.

        • Re:Gold? (Score:2, Informative)

          by Anonymous Coward
          If you want more info, look up info on gold-thiol self assembled monolayers (SAMs). Basically, if you have a gold surface, thiols spontanteously sit down on it in an organized way. If you can attach a thol group to your molecule of interest it is easy to stick it on a gold-coated surface.

    • Re:Gold? (Score:3, Insightful)

      by Mr. Underbridge ( 666784 )
      It's just an element. The scientists in question aren't particularly concerned with its attractiveness, seemingly mystical attraction, or monetary worth. Like any other chemical, it has a range of uses. Here, it's fairly inert from an oxidative standpoint, yet is relatively easy to attach thiol groups to. In addition, it's conductive. Nothing to see here...

    • Re:Gold? (Score:2, Informative)

      by Anonymous Coward
      Gold leaf. Gold is capable of being made a lot thinner and smoother-faced than most other metals and its high conductivity generally makes an excellent substrate for these sorts of uses. SEE ALSO: scanning tunneling microscope and others.

      • Re:Gold? (Score:2)

        by njh ( 24312 )
        I thought very small things like that were done with photo resists and electrodeposition?

    • Re:Gold? (Score:4, Informative)

      by pimpimpim ( 811140 ) on Tuesday March 14, 2006 @07:32AM (#14914653)
      I'm currently doing a research project on biomaterial-surface interactions (which is a huge field, so I might miss out on some points).

      There are several properties that make gold suitable for these medicinal applications. I'll give a few that I took from chem rev 2005, 105, 1103 [acs.org](*).:

      • It can readily form a thiol-bond with sulfur-containing molecules, this allows for sticking lots of stuff to it, synthetic carbon chains, but also DNA and proteins, all by relatively simple techniques
      • It is very easy to create gold layers of a known structure, there are several deposition techniques available.
      • It is biocompatible: less noble metals like Nickel have Nickel atoms migrating into the system, which can kill cells. Furthermore there will be a lot of oxidation going on at those less noble metal surfaces.
      • Gold can be combined with a lot of electrochemical analysis techniques, and others like SPR, MS, etc.

      There are alternatives available, e.g. Palladium, Platinum, but gold is so versatile that it will be the mostly used metal for quite some time I would say.

      (*) the article is mostly about self-assembled monolayers, so not very general and most of it will not be useful to you, but it contains a very good explanation of the reason why people choose gold in any of these applications.

    • I would suppose it has something to do with the ductility of gold, making it the easiest metal to draw out into the extremely thin wires that this would require.

    • I'm a known gold bug and I've been very interested in the industrial applications of gold (partially to gauge demand issues for future supply).

      I don't understand you. If the world (or just the US) were to go on the gold standard, then the gold supply would be artificially scarce, since governments would have to hoard it. That would make industrial use of gold impractical, and gold would cease being useful for many things. Perhaps in the light of medical uses, it would result in the deaths of people to

  • god DAMNIT (Score:4, Funny)

    by Anonymous Coward on Monday March 13, 2006 @11:38PM (#14913172)
    Great, there goes my job.
  • Will these be for sale to the public, I could use one!!
  • Or does the medical research community not care that my life is made hazardous having to work with sweets-scarfing aspartame junkies??

  • Posession of a controlled substance (Score:2, Funny)

    by Anonymous Coward
    How they get the coke for testing?

    um... officer, it's for "medical research"

  • Other uses? (Score:2, Insightful)

    by Saeed al-Sahaf ( 665390 )
    There are already plenty of "instant" drug detection kits, but I wonder what OTHER uses this technology will have?
    • I'll tell you what! I set up a business that sees a lot of cash go through it: a fast-food restaurant or a network of vending machines. I process all cash I take in through some sort of molecular scrubber based on these molecules. I pick up all the miniscule clumps of cocaine that are on the bills. http://www.snopes.com/business/money/cocaine.asp [snopes.com] I then invest those monies back into more cash-accumulating businesses and extract more and more cocaine.
    • You sprinke a suspect with substance X, which your sensor can detect in minute quantities. You can then follow the trail of X using your handy-dandy biosensor, finding everywhere they went, everyone they met, all the money they handled, and their current location.

      Vik :v)

  • UCSB (Score:5, Funny)

    by s0rbix ( 629316 ) on Monday March 13, 2006 @11:43PM (#14913204)
    and seconds after they turned it on, the sensor was activated by a passing UCSB undergrad...

    • and seconds after they turned it on, the sensor was activated by a passing UCSB undergrad...

      I got my Ph.D. at UCSB, and I had to laugh when I read this.
      Adam Sandler played some live shows at UCSB during my years there. The live recordings of at least the first couple of versions of the Chanukah/Hanukkah Song were recorded there, and inside the album What The Hell Happened To Me?, you can see pictures of Sandler at one of those shows, wearing a UCSB cap.
      So I tell people: "Y'know that part of the Han

  • kinky (Score:5, Funny)

    by nEoN nOoDlE ( 27594 ) on Monday March 13, 2006 @11:48PM (#14913233)
    When cocaine is present, the aptamer tightly hugs a cocaine molecule and leans over so that a metal tag can touch the gold surface.

    Sounds kinky. Makes me regret not listening during chemistry class.

  • Competetive technology (Score:5, Funny)

    by SnowZero ( 92219 ) on Monday March 13, 2006 @11:56PM (#14913278)
    There are a lot of "Cocaine biosensors" you could hire off the street for a few dollars ah hour. They will react quite strongly when they find the compound in question (i.e. the "good stuff").
    • There are a lot of "Cocaine biosensors" you could hire off the street for a few dollars ah hour. They will react quite strongly when they find the compound in question (i.e. the "good stuff").

      Yeah, but it's like using pigs to hunt truffles -- you have to ensure the pig doesn't get a chance to eat the truffles, or it's just a waste of time. =)

  • Big deal (Score:5, Funny)

    by Ancil ( 622971 ) on Monday March 13, 2006 @11:58PM (#14913285)
    When cocaine is present, the aptamer tightly hugs a cocaine molecule and leans over so that a metal tag can touch the gold surface.
    You can get the same effect with any garden-variety stripper.
    • You can get the same effect with any garden-variety stripper.

      That's an interesting garden you have. How might I go about planting my own?

  • cocaine? (Score:4, Funny)

    by Simon Garlick ( 104721 ) on Monday March 13, 2006 @11:59PM (#14913286)
    They might as well have named it the $20 bill biodetector.

  • Dogs out of work? (Score:4, Funny)

    by ewg ( 158266 ) on Tuesday March 14, 2006 @12:01AM (#14913301)
    Does this mean all those drug-sniffing dogs are out of work?

  • Much more than cocaine (Score:5, Interesting)

    by Michael Woodhams ( 112247 ) on Tuesday March 14, 2006 @12:02AM (#14913303) Journal
    It has the potential to measure concentrations of thereputic/analgesic drugs too. Imagine an needle with appropriate probes inside which constantly monitor the blood concentration of drugs. Wires lead to an IV control which then administers the drugs at precisely the rate required.

    This is, of course, a very hypothetical future - it might not work out this well.
    • I remeber a role playing game called Rifts that had a class known as the Jucier that had this very technology. They were typlically amped to the maximium body potential, but this cut their average life expectancy to around 5-10 years after getting "jucied"

      See more here Palladium Books [palladiumbooks.com]
    • contamination... physical scraping... oxidation...

      I think there is enough dust and grime to mess up this sort of tech in real-world usage.
    • Yes, but the point is that if you are a college student working on a "cocaine detector" you can get permission to legally purchase cocaine from the DEA ;)

      Seriously, I have to wonder where they get it. They could get it from a drug company, as they have substantial amounts of it, most of which is used to create the various "-ain" drugs, but they might also have simply gone to the source, depending on how much they needed. For those not aware, "the source" in the U.S. is generally Coca Cola. According to the

  • Sweet!!! (Score:5, Funny)

    by LandownEyes ( 838725 ) on Tuesday March 14, 2006 @12:03AM (#14913307)
    No more crawling on the floor at 4am!!!

  • Go nuts around money-counters (Score:3, Interesting)

    by fuzzybunny ( 112938 ) on Tuesday March 14, 2006 @12:04AM (#14913310) Homepage Journal
    Maybe they could install these in banks and have them thrown out after about 5 minutes because the staff were going nuts about the constant beeping every time they counted $100 bills...

  • testing (Score:4, Interesting)

    by evoltap ( 863300 ) on Tuesday March 14, 2006 @12:05AM (#14913326)
    One would hope that this would lead to methods that would be available to employers who currently only test for marijuana. Supposedly cannibus will show up even it it was consumed a month prior, cocaine on the other hand does not show up.

    Of course if you look at the history of the CIA in the 80's, one might hypothesize that the government has no interest in stopping cocaine consumption.

    At least we all know marijuana is very bad.....there's this new movie out, Reefer Madness......really informative.
    • I wonder if the over crimilization of Marajuana and the more relaxed stance (still crimilaized but not as evident) on cocaine because cocaine is more of a productivity generator while marajuana is more of a demotevator?

  • If This Thing Short Circuits (Score:3, Funny)

    by highwaytohell ( 621667 ) on Tuesday March 14, 2006 @12:07AM (#14913332)
    Do users get a different type of buzz?? Bet Robert Downey Jr will try to quash this technology ASAP.

  • big surprise (Score:4, Funny)

    by schematix ( 533634 ) * on Tuesday March 14, 2006 @12:09AM (#14913342) Homepage
    As a recent grad of UCSB, i'd have to say they picked the perfect place to develop a cocaine sensor. The students and faculty will have no problem finding suitable substances to test it on.
  • "attaching a special"... "an aptamer to a gold electrode."... "...the aptamer tightly hugs..." "...and leans over so that a metal tag can touch the gold surface. This causes a spike in a plot of current versus voltage when the electrode is attached to a machine called a cyclic voltmeter."

    heheh Funny... slash imageword: "straps"
  • [...] created a biosensor by attaching a special type of DNA called an aptamer to a gold electrode.

    The difficult bit was persuading George W Bush to swap the silver spoon for a gold one.

  • Convience (Score:2, Funny)

    by Joebert ( 946227 )
    Theese things are going to end up for sale on the counters at convience stores, right next to the roses in the little glass tubes & the brillo pads...

  • The real trick is.... (Score:5, Funny)

    by canning ( 228134 ) on Tuesday March 14, 2006 @12:43AM (#14913477) Homepage
    At-home pregnancy tests are the model of diagnostic simplicity: a tester just pees on a stick and within minutes knows if she has to buy a crib. Imagine if one could just as easily detect HIV infection or a drug overdose.

    The real challenge is getting the corse to pee on the stick. I suggest the 'old hand in the warm water' trick.

  • This is it! (Score:3, Funny)

    by typical ( 886006 ) on Tuesday March 14, 2006 @01:19AM (#14913601) Journal
    Now the War on Drugs will *surely* be won in short order!

  • Extensive research, measured in kilos (Score:5, Funny)

    by smoon ( 16873 ) on Tuesday March 14, 2006 @01:23AM (#14913611) Homepage
    It ended up taking about 68 kilos of cocaine to finally nail down the winning formula, reported biochemist George Placky. "We put in a lot of long nights, in fact we frequently would stay in the lab for 72 hours straight." "The team worked so hard we tried to accomodate them wherever possible." Indeed the lab is awash with stereo equipment, couches, and large screen TVs.

    Univeristy officials confirmed the long nights. Security guard Paul Costas remakred "Yeah, those guys were going at it for days on end. I helped them smuggle chicks into their parti..ahh *research*."

    "We feel that with another couple of years we will have similar sensors for crystal meth, heroin, and extasy." said Dr. Placky, who is currently applying for federal grants to fund the research, as well as provide sufficient quantities of the substances for thorough research.

  • Addendum (Score:3, Funny)

    by c0dedude ( 587568 ) on Tuesday March 14, 2006 @01:29AM (#14913631)
    When asked if the device could register false positives, the researchers responded, "She don't lie, she don't lie, she don't lie; cocaine."
  • anyone residing around the area will know what I'm talking about.

    I'm sure they had all the coke they needed for testing.

  • Who cares? (Score:3, Informative)

    by TallMatthew ( 919136 ) on Tuesday March 14, 2006 @06:41AM (#14914536)
    Returning instant results doesn't mean anything if the drug's not in your system.

    Cocaine has a plasma half-life of 90 minutes. Current cocaine drug tests detect metabolites, not the drug itself, and even those only work within 24-48 hours after using.

  • That government installed biosensor on your sewer outlet won't need a warrent.

Slashdot Top Deals

It is easier to write an incorrect program than understand a correct one.

Close