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HPLC Application Sheet #121
Basic Compounds
Column: Cogent HPS C18, 150mm x 4.6mm
Type of Hardware: Super-Link System
Catalog Number: 75018-15 or 75018-15R
Flow Rate: 1.0mL/min
Temperature: Ambient
Detection: 254nm
Injection: 10µL
Mobile Phase: 60:40 Methanol:Water
Test Mixture: Uracil/Pyridine/Phenol
Click Here to view stationary phase specifications
Click Here to view chemical structures of analytes
Peak
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tR
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k'
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Symmetry
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USP Tailing
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N/M
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1: Uracil
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1.73
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0.00
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1.21
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1.12
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47,240
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2: Pyridine
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2.52
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0.46
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3.26
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2.54
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32,113
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3: Phenol (Carbolic Acid)
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3.09
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0.78
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1.03
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0.99
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70,220
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Discussion of Chromatogram:
This is an industry standard method to show the relativity of peak shape and efficiency of phenol and pyridine. This
un-buffered test is used by column manufacturers to define the residual silanol site and trace metal activity of the
stationary phase. With older “base deactivated” technology products in the market, the pyridine peak would elute
after phenol and tail to unacceptable levels
(click Here to view Comparative Chromatograms) in these un-buffered conditions. The peak
shape and efficiency of pyridine could be easily optimized with a buffer. This column is an excellent choice for
many basic compounds.
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