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Microfluidics: Miniature Chemistry Labs

Posted by michael on from the make-jello-using-one-third-vodka dept.

enkidu writes: "The NYTimes has a story (free reg, yaba yaba) about the rapidly emerging field of microfluidics and describes some of the methods used in making micro-valves, pumps and other components. In the future, you won't need to send your blood/urine sample to a lab, your doctor will put in his "lab-in-a-box" and hand you a printout before your leave."

57 comments

  1. But the insurance companies won't allow it... by printman · · Score: 5, Insightful

    A lot of doctors ran out an bought their own mini-lab test equipment when it first came out. Not only did it cost them less than sending it out to be processed, but they got results faster.

    *However*, the insurance companies have put a stop to that. My doctor has to send out my bloodwork and wait almost a week to check my cholesterol, instead of using his own equipment and getting me an answer within an hour or so... In the process, I end up paying *more* to my insurance company and they get to negotiate mass-quantity lab work with the lowest bidder.

    --
    I print, therefore I am.
    1. Re:But the insurance companies won't allow it... by Anonymous Coward · · Score: 1, Funny

      How dare you criticize the free market, implying that they are somehow trying to gouge you. The Free Market (tm) will not tollerate such heresy. The insurance companies are simply trying to make a profit which benefits all humanity. You are hinting that these individual doctors somehow know better than large, holy corporations.

    2. Re:But the insurance companies won't allow it... by cplmd · · Score: 5, Insightful

      As a physician, it's not just the insurance companies to blame - if fact not them at all. It's how our wonderful federal government responds to a few of my unscrupulous colleagues.
      Specifically, Rep. Pete Stark in his three versions of Stark Acts have reduced how much a physician can do for you. Pharmacies, labs and x-ray cannot be owned or used by the doctor if he does have an interest in the facility. I don't have a problem with that given the kickbacks a few doctors got in the past.
      However, as always with federal regulation of individual/local problems, it has extended into areas that no longer make sense and actually make it worse for you as a patient. This office-lab in a box being a case in point.
      While on my soap box, it would be nice if the federal government limited and regulated the legal, esp. civil court system as much as the medical one. Given spiraling malpractice insurance costs and the actual closure of some rural hospitals due to legal liability and insurance costs, maybe as the federal government did with medicare/medicad in setting limits on what reimbursement would be to doctors and hospitals for a given disease, lawyers in this country should be limited in what they are paid for say a divorce, murder defense or malpractice / workman's comp. case.

      --
      just leave me alone and i'll leave you alone - there - isn't that easier and better?
    3. Re:But the insurance companies won't allow it... by Anonymous Coward · · Score: 0

      Which would I rather do...

      Hmm... I bet it's safe to assume that the lab company charges more (even though it is larger, economies of scale, etc.), too, because they can. They have created a near-monopoly...

      And what about some of the problems with lab companies? Lab Corp had a big problem with the FDA a few years ago, for example...

  2. Daily drug screenings! Yay! by 13013dobbs · · Score: 2, Interesting

    *sigh* Now it will be easier for employers/cops/whoever to scan people for evil drugs.

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    No replies made to AC posts. Please log in.

    1. Re:Daily drug screenings! Yay! by Anonymous Coward · · Score: 0
      *sigh* Now it will be easier for employers/cops/whoever to scan people for evil drugs.


      Isn't this a good thing, being more able to determine who is breaking the law? If you have nothing to hide, what are you afraid of?

  3. sorry, your blood sample was declined by Anonymous Coward · · Score: 1, Insightful

    blood testing in a handheld reminds me of Gattaca.
    shudder.

    1. Re:sorry, your blood sample was declined by core10k · · Score: 0

      That's what I thought too. Turns out those pin pricking machines are nearly identical to the handheld machines that Diabetics use to test their blood sugar level. (I'd never seen one at the time, so I didn't realize how common they were)

      --
      Go Kathryn Thurber!
    2. Re:sorry, your blood sample was declined by transcend.ca · · Score: 1

      I wonder if the "handheld devices able to detect anthrax in a room" could be adapted to work like today's face-recognition camera systems, where a detector scans a room passively for traces of DNA that are known to be from a criminal, whose DNA is in a database. Possible?

  4. Obligatory no-reg link by no+parity · · Score: 4, Informative

    http://college.nytimes.com/2002/01/01/science/phys ical/01MICR.html

    1. Re:Obligatory no-reg link by Anonymous Coward · · Score: 0

      Maybe /.'s lame lameness filter can actually do something useful for a change and modify all the lame-ass NYTimes (free reg, yada yada) links to no-reg links. Now there would be a useful /code mod!

    2. Re:Obligatory no-reg link by Jack+Greenbaum · · Score: 1

      cypherpunks:cypherpunks almost always works at NYT.

  5. On the hardware side... by danamania · · Score: 2, Interesting
    I wonder if this could be a useful thing in cooling circuitry such as CPU's. Build a cooling system into the CPU itself. perhaps an ultra-efficient heatsink which pumps liquids through tiny channels in thin fins - anything to help heat dissipation.

    ...or combine the medical side of it and pump your own body fluids through your cpu - ooah. scary.

    1. Re:On the hardware side... by Anonymous Coward · · Score: 0

      Oh great. Oh joy. Now I got to use under fin anti-perspirant (sp?) for the CPU ?

    2. Re:On the hardware side... by rgmoore · · Score: 2, Interesting

      Unlikely. The flow that you can get through a very small channel is absolutely tiny. Over a large range, the backpressure goes up as one over the square of cross-sectional area, so a large array of small channels can allow substantially less flow at a given pressure drop than a single large channel of the same area. Using channels the size that you can make using this kind of process you simply aren't going to be able to get enough flow to make much difference.

      (BTW, I do have some idea of what I'm talking about; I've worked in microfluidics and still work in a closely related field.)

      --

      There's no point in questioning authority if you aren't going to listen to the answers.

    3. Re:On the hardware side... by deglr6328 · · Score: 2

      "...or combine the medical side of it and pump your own body fluids through your cpu - ooah. scary."

      'OH NO! He's crashing!.. Code Blue!'

      takes on brand new meanings!

      --
      - "Hear that?! The percolations are imminent! Cease your ingress!"
  6. In other news... by BinaryAlchemy · · Score: 1

    A man spontaneously combusted today while trying to cool his new Athalon25000 with his own blood.

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    ----- The problem with browsing at +5 is that everyone thinks you're being redundant
  7. In the what? by Anonymous Coward · · Score: 0

    No offense intended, but isn't the phrase "in the future" a little outdated?

  8. Re:On the human side... by savaget · · Score: 1

    Cooling a chip is great but,I wonder how many lives this will save by having portable labs available everywhere in the worlds.

  9. Won't this hurt accuracy? by diamond0 · · Score: 3, Interesting
    Due to the small samples such a machine would process, the error margin is bound to be huge. This is elementary statistics, folks; if you want milligrams per deciliter of blood cholesterol, or any sort of statistic about a body fluid, the more of a sample available to the process, the more accurate it's going to be. Compare this to Nielsen surveying only twenty people, or Gallup only a hundred.

    I've been wrong before; maybe a biochemist could chime in and let us know how much blood or urine constitutes a true statistical sample?

    --

    --
    There is no hatred more pure and true than that expressed by children.
    1. Re:Won't this hurt accuracy? by baz00f · · Score: 5, Informative

      Speaking as a pedigreed biochemist, you are correct in the extreme of vanishingly small samples. But these devices are still working with enough volume such that an analyte of interest at a substantial concentration (glucose, cholesterol, etc.) is effectively present at the same concentration at nearly all sample volumes.

      Things DO fall apart (as you intuit) when the concentration of the analyte gets vanishingly small. We see this routinely when we try to quanitate DNA using PCR (Polymerase Chain Reaction) methods. PCR is sensitive enough that we can detect ONE copy of a DNA molecule in a volume of sample. So if you have say, one copy in 1ml of volume, and you sample .1 ml and do your PCR, your test would come up negative upon repeats (on average) 9 out of 10 times. With small numbers of copies you can use Poisson statistics to calculate your hit rate. With higher concentrations your Poisson distribution collapses to a gaussian that gets narrower and narrower, which is the regime that most normal wet analytical techniques work. For example, fasting blood glucose is about 100 mg/dl, which is about 5 mM. Assuming your device can work with 1 nanoliter sample size (this is about 100x smaller than a volume about the size of the proverbial period at the end of a sentence) you would have 3x10^12 molecules of glucose in it. Assuming your technique is sensitive enough to register the presence of this "small" number of molecules, you are still far away from seeing sampling errors on repeats of the same sample due to random fluctuations of the number of molecules (the "concentration") in any given sample.

      Paul Yager at U. Washington (Seattle) has a good introduction to microfluidics:

      Microfluidics Tutorial and Prognostication

    2. Re:Won't this hurt accuracy? by danamania · · Score: 2, Interesting
      I posed this question to a friend who does work with testing body fluids in a lab, and her response was that since there -are- minimum sample sizes, one small test on a tiny scale could certainly have errors on a different scale to current tests.

      My guess is by looking at the relative complexity (in number of components) of the pumps/mixers/detectors compared with a several hundred million transistor CPU, that an array of perhaps millions of separate testers could be easily built, one which would run millions of simultaneous tests.

      Only comparing those results with known working ones would show if the results were comparable - certainly one more type of testing can't hurt, and if it only proves extra accuracy in a few cases, they may be ones with a great impact.

    3. Re:Won't this hurt accuracy? by Vinson+Massif · · Score: 2, Informative

      Analytical volumes are in the mL range to ease handling and to minimize cumulative error. In most modern techniques, microlitres are taken up by the test instruments; the actual amount of 'stuff' that is actually analysed is minute. Good test design and bench technique give good results.

      It's not the sample volume I'd be questioning, but calibration, standarization, and QA procedures. These are the root of inaccurate (and imprecise) test results.

      --

      --
      "Remember, any tool can be the right tool." -- Red Green
    4. Re:Won't this hurt accuracy? by uncadonna · · Score: 1

      I really wish people wouldn't assume that they can spot an elementary error in published science upon five minutes thought. You'll invaribaly find that they have already thought of and dealt with your show-stopper.

      It's widely believed that climate change models "don't account for water vapor", too. It amazes me that people can convince themselves that scientists can work on a project for years and still miss things that are obvious to amateurs.

      There's plenty wrong with science these days, but still it's just about impossible to be transparently wrong in the hard sciences. Subtly wrong, sure, nut not obviously wrong.

      This posting was basically a nice question, but something about the way it was asked bothers me a lot.

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      --
      mt
    5. Re:Won't this hurt accuracy? by red_gnom · · Score: 1

      This is absolutely truth.
      For the best results doctors should take no less than five liters of the patient's blood for testing.

    6. Re:Won't this hurt accuracy? by SillySlashdotName · · Score: 0

      Yup, you are wrong.

      I am diabetic, and I check my blood glucose levels. I use a small portion of one drop of blood. For each test, the population of the test is ONE, and the volumn of the sample is small. I (and my doctor) still trust the results, because the test is STANDARDIZED, i.e., if such-and-so procedure is followed, and you use these strips in this machine which has been shown to give the following value when used with that specific control solution, the results will correlate closely with independent lab analysis of a much larger sample.

      In the hospital, the Blood Glucose Monitoring machine used on the floors is required to be calibrated (checked against known solutions) at least daily, and preferably more frequently. This means I may not check a CBG (capillary Blood Glucose) for several weeks, but when I do, the test will give a result that correlates well with 'actual' (determined by any laboratory) values.

      I work for a hospital (in IT now, but I am a LPN as well and worked in patient care for several years), and a considerable cost in the lab is the "control solutions" needed to check that the machine is giving the same results to a known solution as other labs. I would assume a major concern is/was that physicians would not run the controls as frequently as independent labs do (due to the costs) and would therefore have invalid results on which they were basing their decisions - maybe to the detriment of the patient.

      >>Compare this to Nielsen surveying only twenty people, or Gallup only a hundred.

      Better yet, compare this to Nielsen or Gallup surveying only a few thousand and then stating what millions of people NOT surveyed were doing/thinking/watching - which happens so frequently it is not often thought about, and shows that, if valid techniques and procedures are used, the results can be amazingly accurate and usable.

      --
      Acts of massive stupidity are almost never covered by warranty. --me.
  10. Re:Serious buffer overflow found in Linux-2.4.17 by Anonymous Coward · · Score: 0

    Another overflow error again!
    Well that's it, starting tomorrow,
    I'm going remove linux from all 3,014
    computers at work and install winXP.
    With the XP volume licensing scheme,
    I will save alot of money over buying
    3,014 XP professional licenses individually
    In fact, so much money that it will be like
    losing money if I don't go with the microsoft
    solution.

    --Bill G.
    --Tech Guru/Senior Sysadmin

  11. Incredible Shrinking Labs by Anonymous Coward · · Score: 1, Informative

    http://www.ornl.gov/ORNLReview/meas_tech/shrink.ht m
    A small blurb on Dr ramseys work.

    http://www.chipcenter.com/columns/bmcginty/col01 2. html
    Another article on fludic chips.[check the links at the bottom]

  12. Solution by Wire+Tap · · Score: 1

    Just tell the insurance companies to get outta town. Really, if enough people, at once, stood up against their bull crap, they would have to cave.

    --

    Man is born free; and everywhere he is in chains.

  13. Re:1/1/2002 by Anonymous Coward · · Score: 0

    It's Sam Sloan, frequent rambler on a great number of Usenet groups. Try searching for his name on groups.google.com...

  14. Great news... by cperciva · · Score: 2

    next time my doctor needs to take a blood sample maybe they'll be able to take a small enough quantity of blood that I won't faint. It's not a problem if they only need to run one test, but when they need four or five tests this will be a major improvement.

    --
    Tarsnap: Online backups for the truly paranoid
    1. Re:Great news... by jhoug · · Score: 1

      The amount of blood taken for normal analysis isn't enough to give you direct physiological symptoms. The psychosomatic issues are generally the cause of dizzyness and fainting ( your brain, quite rightly, doesn't want you to have holes in vessels, or to give up any blood. Dropping your blood pressure to reduce blood loss is an evolutionary good thing).
      A fingerprick will give enough volume for microsampling, but the number of fainters will diminish, not disappear. I volunteer at Red Cross blood drives, and I've seen a high-school football player faint from the fingerprick. I've also seen non-donors have issues (bring a friend for "moral support", watch THEM collapse!)
      Anyone who tries to give blood is a hero, and those who are uncomfortable with the proccess, but donate anyway are bigger heros...

      --
      Recursion: To curse repeatedly.
    2. Re:Great news... by lines · · Score: 1

      I'm wondering if this also means that blood samples can be taken via different routes? No need for blood from the vein if a finger-sitck will do.

      --
      to e-mail, remove '.dot.' from the address
  15. Sweet! by roystgnr · · Score: 1

    I'm supposed to be researching microfluidics before I get back to meet my advisor after vacation. I wonder how one would reference Slashdot in a footnote... ;-)

  16. sample size by Anonymous Coward · · Score: 0

    ..you won't need to send your blood/urine sample to a lab, your doctor will put [it] in his "lab-in-a-box" and hand you a printout before your leave.

    I have enough problems with the little cups, and now I've got to pee into something much smaller?

  17. Dr. Quake by Tsar · · Score: 2

    It's interesting to see Dr. Stephen R. Quake's name cropping up again in one of these stories. His group is working on some amazing stuff, mostly working with one molecule at a time—although, admittedly, they're moby molecules.

    No, I wasn't going to comment on his framerate.

  18. the FUTURE by Anonymous Coward · · Score: 0

    no, in the future, disease of any kind will not exist. I predict that micro-fluidics will be used to make the zaniest curvey-straw ever devised.

  19. URL Citations by Anonymous Coward · · Score: 0

    Actualy a good question. The WWW is a valuble tool for researching almost any topic. Web based research papers can use links to the relevent documents in their citations. But that is only a partial answer. Web based information can be somewhat transitory. The idea of a citation is to provide enough information that one could go to a library and find thw document being cited. Is a URL sufficient? And how does this relate to DeadTree papers? What is the correct form for citing a Web Based document? Maybe an "Ask Slashdot" topic?

    BTW, it is *a* yoo-are-ell (URL), not *an* er-al (url) in the sentence above. Which brings up another topic. With all the terms that are refered to by initials, of wich only some can be used as acronyms and only some of thouse were intended as acronyms, how does one know the difference. Remember, that an acronym is a *word* made from parts of other words, e.g. Radar, Gimp, and Wac. Other terms are mearly initials, e.g. WWW, NAACP, and WAC. Notice that WAC and Wac refer to the same thing. WAC became Wac through common usage. Is there any informatiion regarding the currently accepted status of such things as URL? This makes a difference. As a programmer a large part of my job involves documentation, reports, and proposals. This part of the job is as important as the code I write. It needs to be handeled with the same degree of profesionalism as programming.

  20. Hear Hear! by Anonymous Coward · · Score: 0

    As a neuroscience grad student - I HATE to see this sort of thing on Slashdot, but the ugly truth is that geeks (all of us) tend to have big egos, and lots of people here think that because they know POP protocols, Perl, C/C++, and PHP, etc. that this somehow makes them able to critique EFFECTIVELY scientific theories and papers that they have no experience in.

    Hell, I don't think that I MYSELF have enough knowledge or experience to critique NERUO papers yet!

    But such is life, and such is Slashdot - where people think that Science-Fiction movies (Jurassic Park, Gattaca, Terminator, 2001, etc.) have real relevance to genetic engineering, robotics, AI, etc, and use them as arguments for their opinions on such matters.

    Sincerely,
    Kevin Christie
    Neuroscience Program
    University of Illinois at Urbana-Champaign
    crispiewm@hotmail.com

  21. Whay not in manual??????? by MercTech · · Score: 1

    I find the use of a lab for routine blood work lucridous. It takes a half hour to run a routine spectrum of blood work manually.
    My own physician finds it lucridous that the HMO he is affiliated with will not allow him to draw his own blood nor do his own routine tests. Hell the lab charges $145.00 for a CBC that he could have done in his office for $35.00

    --
    NRRPT/RCT