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Subject: Microscale chemistry

Microscale chemistry

From: Walter Henry <whenry>
Date: Wednesday, May 23, 1990
The following appeared in sci.chem on usenet.  If someone has the energy
to check this out, it could lead to some really valuable bench
applications.  For those of us who have attempted to reduce drastically
the volume of solvents (etc.) used in treatments, microscale might
provide some useful insights, tools, and techniques (not necessarily in
that order).

    >From: SLZ7P [at] cc__usu__edu
    Newsgroups: sci.chem
    Subject: Re: Microscale? (Where to get, etc...)
    Date: 22 May 90

    >I recently heard a talk by R. Nader and he mentioned a
    >product/process called microscale that allows chemistry students to
    >use a fraction of the chemicals that conventional techniques
    >require.  Does anyone have information about this?  Thanks

    >I believe he was referring to microscale experiments.  Basically
    >each student has a set of reagents in small sealed squeeze tubes
    >similar to eye droppers which contain only about 10 ml of reagent.
    >A whole variety of experiments

    I took an organic lab using microscale and actually it worked very
    well. Our department bought kits (Micro Kit , Mayo-MO-1, Cat. No.
    94305-99) which are sets of fully functional organic glassware with
    everything necessary to do distillation, refluxing, separation,
    recrystallization, etc. with a text book (Mayo, Pike, and Butcher,
    Microscale Organic Laboratory, John Wiley & Sons, 1986) specifically
    written for these kits.  Everything is done exactly the same as
    normal synthesis except you work on the microliter/milligram scale
    (which apparantly saved the department enough money to pay for the
    kits in less than three years though I don't have any exact
    numbers).  Also, due to the much smaller volumes involved, hoods
    only had to be used in a few isolated cases and the risks of fire
    and chemical spills were almost eliminated (I never saw either the
    whole time I was in lab).  You might want to write to our chemistry
    dept. here for more details.

             Utah State University
         Dept. of Chemistry and Biochemistry
         Logan, UT  84322-1619     (801) 750-1619

    Anyway, I hope this helps.

    | S. Beck                     | Address as of this summer:  |
    | slz7p [at] cc__usu__edu            |   Quantum Theory Project    |
    |   (or slz7p [at] usu__bitnet)     |   University of Florida     |
    |                             |   Gainesville, FL  32611    |

    >From: dove [at] ucscb__UCSC__EDU (Ray Rischpater)
    Newsgroups: sci.environment,sci.chem
    Subject: Re: Microscale?
    Summary: Explanation of what it "entails"
    Date: 22 May 90
    Organization: UCSC Open Access

        Microscale isn't so much a process as it is a collection of
    techniques which allow students to perform organic reactions on a
    very small scale, utilizing very small quanities of reagents.  This,
    of course, results in saving lots of chemicals and lowering the
    waste output from educational sites.

        The average student's microscale setup consists of several small
    (1.0 - 3.0 ml) vials, a small (needleless) syringe for measuring
    fluid volumes, very small replicas of distillation columns which can
    screw directly on to the small vials, and the like.  Several items,
    such as a distillation collector (to collect the products of a
    distillation) have been very cleverly re- engineered considering the
    small scale.  For instance, the aforementioned distillation
    collector (called a Hickman still) consists of a glass tube which
    has a fat bottom and skinnier top.  The bottom base screws into the
    top of the vial, and has a lip in it to collect condensation which
    collects on the sides of the still.  Typically, all of this
    glassware is screwed together and sealed using ground glass joints
    and rubber (Teflon?  I'm not sure) washers.

        Reactions using microscale are performed using around 0.01-0.04
    moles of reagents (someplace on the milligram level, usually), as
    opposed to "normal" (macroscale) educational labs, which are
    anywhere above the 0.1 mole scale.

        (As a student who has just finished a year-long course in
    Organic Chemistry) I think it's a really nifty technique.  We use it
    a lot with chemicals which we know to be nasty for the environment,
    or overly expensive. There are also times where (becuase of
    mistakes, say, or when analyzing a limited amount of an unknown
    compound) where microscale becomes incredibly convenient.

        I hope that answers your questions.  Feel free to mail me if you
    like; I could send you some actual details of labs incorporating
    this technique.

    dove [at] ucscg__ucsc__edu                 Ray Rischpater
    dove [at] ucscb__ucsc__edu                     Cowell College #707
    (408) 426-0716                      UC Santa Cruz
                                Santa Cruz, CA 95062

                   Conservation DistList Instance 3:8
                  Distributed: Wednesday, May 23, 1990
                        Message Id: cdl-3-8-008
Received on Wednesday, 23 May, 1990

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