Resumo (PT):
Abstract (EN):
In this manuscript, the separation of kahweol and cafestol esters from Arabica coffee brews
was investigated using liquid chromatography with a diode array detector. When detected
in conjunction, cafestol, and kahweol esters were eluted together, but, after optimization,
the kahweol esters could be selectively detected by setting the wavelength at 290 nm to
allow their quantification. Such an approach was not possible for the cafestol esters, and
spectral deconvolution was used to obtain deconvoluted chromatograms. In each of those
chromatograms, the four esters were baseline separated allowing for the quantification of
the eight targeted compounds. Because kahweol esters could be quantified either using
the chromatogram obtained by setting the wavelength at 290 nm or using the deconvoluted chromatogram, those compounds were used to compare the analytical performances.
Slightly better limits of detection were obtained using the deconvoluted chromatogram.
Identical concentrations were found in a real sample with both approaches. The peak areas
in the deconvoluted chromatograms were repeatable (intraday repeatability of 0.8%, interday repeatability of 1.0%). This work demonstrates the accuracy of spectral deconvolution
when using liquid chromatography to mathematically separate coeluting compounds using
the full spectra recorded by a diode array detector.
Language:
English
Type (Professor's evaluation):
Scientific
No. of pages:
9