www.CogentColumns.com
Hello.
My name is Professor Joe Pesek and I am the inventor of Cogent TYPE-C silica hydride phases.
From the beginning of their development, these columns showed us that they were unique and
could be the inception of a new phase for HPLC making data less expensive and easier
to obtain.
The character and benefits of these columns have been shown over the last 15 years
to be remarkable for long life time, faster to equilibrate than ordinary columns and able
to retain polar compounds with remarkable precision and with little buffer used.
I am sure you will enjoy using these columns and will get plenty of great data from them.
HPLC, particularly in combination with Mass Spectrometry, has become one of the most important
analytical techniques available to a large number of chemists and other scientists.
Analyses span a broad range of applications such as biotechnology, pharmaceuticals, forensics,
food quality, clinical measurements and chemical product development using instruments such
as the one you see behind me.
A variety of Cogent Type-C columns are available as tools for solving challenging analytical
problems in these and other fields of application.
To illustrate the utility of Type C columns in a simple practical analysis, histamine
in red wine is determined on a Cogent column, the Diamond hydride.
Histamine is known to cause allergic reactions in many people.
This column is used because histamine is very hydrophilic and the Diamond Hydride is particularly
effective for polar compounds.
First we will demonstrate the sample preparation used for this analysis.
A known amount of red wine and buffer are added to a sample vial.
The sample is now ready for injection into the HPLC MS instrument to analyze for histamine.
The data obtained for this analysis is illustrated in the following series of extracted ion chromatograms
at the exact mass for histamine.
The first chromatogram is the data obtained for a red wine sample where the winery claims
to have low levels of histamine.
As seen, there is considerable background noise in this data but not any distinct peak
for histamine.
The second chromatogram is a standard histamine sample used to identify the retention time
of histamine.
The third chromatogram is the same sample used in the first analysis but spiked at the
level of 10 parts per million histamine.
This last data proves the winery's claim that its red wine is low in histamine since
the 10 parts per million spike provides a strong signal in the wine matrix.
Due to the unique composition of the Cogent Type C columns, the three analyses shown are
done consecutively with only a three minute reequilibration time between injections.
Our second example is the analysis of critical polar metabolites that are part of the uric
acid cycle.
Shown in the first figure is a comparison of the optimized data obtained on two different
columns, the Diamond Hydride and the Cogent Diol.
This data illustrates the importance of proper column selection.
While the Diamond Hydride can retain these analytes adequately, separation is much better
on the diol column.
Two of the critical analytes are 6-aminouracil in black on the DH and then on the diol in
red and the second, allantoin, first on the DH in black and then on the diol in red.
The last panel is an overlay showing the superior separation on the diol in red vs. the DH in
black.
The second set of results is a series of repetitive injections of the sample analyzing uric acid
in urine with a 3 minute equilibration time between runs.
The first injection is the standard followed by three urine sample analyses.
As shown, the retention times of the consecutive runs are virtually identical.
This is another important feature of the silica hydride phases when analyzing polar compounds
and such precision, usually 0.2% or less, is generally not possible by other chromatographic
methods used for the determinations of hydrophilic analytes.
I hope that you have enjoyed this short presentation about our Cogent Type C columns.
They are being used in laboratories around the world from determining food composition
in South America and the United States to pharmaceutical analyses and medical investigations
in Europe, the United States, and Australia.
For more information or to order our columns please contact us.
Our contact information is in the notes below the video.
www.CogentColumns.com
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