Capillary column development
 "Marcel
Golay joined Perkin-Elmer as a consultant after a 25 year distinguished career at the U.S.
Signal Corps Engineering Laboratories in Fort Monmouth, New Jersey. he was originally
trained as as an electrical engineer and mathematician at the Federal Technical University
of Zurich, Switzerland. He received his PhD in nuclear physics from the University of
Chicago. His connection with Perkin-Elmer was mainly due to to his involvement in the
development of an IR detector, originally conceived as an aircraft detecting device, and
of a multiple-slit IR spectrometer.
When Golay joined Perkin-Elmer, everybody was excited by the versatility and the
incredible separation power of GC; inevitably, he also became involved in various
discussions of the new technique, which was a totally unknown field to him. He became
intrigued by the mathematics of the separation process, and, being an electrical engineer
by training and experience, he tried to interpret it with the help of the Telegrapher's
equation used to describe the process in transmission lines. He presented this unique
comparison at the GC symposium organised in conjunction with the Spring 1956 National
Meeting of the American Chemical Society.
In subsequent months Golay continued to investigate - at first theoretically - the
separation process occurring in the packed chromatographic column. To simplify the system,
he constructed in his mind a model consisting of a bundle of capillary tubes, each
corresponding to a passage through the column packing. These ideal capillaries would be
unrestricted by the geometry of the packing or the randomness of the passages through it,
which are beyond control. Therefore, the capillaries should behave close to the
theoretical possibilities. Golay's considerations were outlined in a number of internal
reports, of which the one dated 5 September 1956 was the most important. In this report he
suggested some experiments with a capillary tube 0.5 - 1mm in diameter. and wetted with a
suitable stationary phase, which corresponded to one of these passages."
Leslie S. Ettre. Evolution of Capillary Columns for Gas Chromatography. LCGC
19(1),48-59, (2001)
see http://www.lcgcint-mag.com/
for the full article and others by Leslie Ettre on the history of chromatography.
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M.J.E. Golay. Preparative Capillary Chromatography - A Proposal
".....this narrative will again start in 1941 at the Signal Corps Laboratories
where I was trying to develop a system of infrared detection. I had to use long brass
tubes which gave me some trouble, and I assigned the trouble to the presence of dirt or
oil on the inside wall of the tube. This gave me the idea that if I had a mixture of
several substances in a gas, the various affinities of the different components would
cause a difference of speed between these components, so that they could be separated.
Well this looked to me like a kind of dry distillation and it looked too good to be true.
I reasoned , brilliantly, that if it were not true then I should forget it, and if it were
true , then surely it must have been part of the bag of tricks of the chemist for a
century. So I went back to infrared detection and dry distillation went into limbo where
it was to stay for 15 years.
Some 14 years later, my friends asked me to make sense out of packed chromatographic
columns, which were just emerging at that time in 1955. Eventually I was to appreciate the
three major virtues of the packed column, but not immediately. I admit that I was at sea
at first regarding what was going on, and the name "chroma" or
"chromo" did not help a bit. However, I noticed a similarity between what
happened to a component going down a chromatographic "line", or a
chromatographic column, and what happens when you inject a signal into a telegrapher's
equation. I developed this little idea into a very learned theory, which, in 1956 at
Dallas, I expounded in front of a distinguished group of analytical chemists, who
understood nothing of it, but missed nothing either because all I had done was to show
what was already suspected, namely that there was an optimal flow rate in the column.
Well, when my friends asked me to stick numbers into my equations, I found them quite
useless, so I stated to think physically as to what went on in a chromatographic packed
column. And then I realised the first virtue of the packed column. It had granules
impregnated by a retentive substance and the flow of the various components of a mixture
going by these substances was not the same, and as the velocities were not the same for
all the components, they became separated. This was dry distillation rediscovered, and my
friends were able to assure me that dry distillation in an open tube just did not exist.
So I made a small calculation which indicated that, pricewise, an open tube was ten
thousand times better than a packed column, and by "price" of a distillation I
mean the product of the pressure differential at both ends of the column by the time it
takes for an analysis. A factor of ten thousand meant that we could do in one second with
an open tube what it would take three hours to do with a packed column. So there was
nothing for it but to try it. It didn't work quite as well as I had hoped, but it worked.
The reason it didn't work as well as I had hoped I ascribed to the time of diffusion into
the thick coating on the tube, a coating of several microns perhaps. And so I came to
discover the second big virtue of the packed column, which was that it used granules that
were porous where the fixed phase was highly divided. This led to the idea of porous lined
open tubes, which became known eventually as SCOT columns, although later on good coatings
were discovered which made this unnecessary."
M.J.E. Golay. Preparative Capillary Chromatography - A Proposal. Journal of High
Resolution Chromatography & Chromatography Communications. Vol. 11, January 1988, pp
6-8 |
