posted on 2020-01-15, 20:42authored byDecibel
P. Elpa, Shu-Pao Wu, Pawel L. Urban
Extraction
of volatile compounds from complex liquid matrices is
a critical step in volatile compound analysis workflows. Recently,
green chemistry principles are increasingly implemented in extraction
processes. Some of the available approaches are solvent-free but still
require concentration or trapping of analytes. Here, we propose effervescent
tablet-induced extraction (ETIE) as a method of transferring volatile/semivolatile
compounds from liquid matrices to the gas phase for analysis. This
technique relies on the release of carbon dioxide produced in situ
during a neutralization reaction, which occurs when a tablet is inserted
into an aqueous sample matrix. In this process, many bubbles of carbon
dioxide are instantly formed in the sample matrix. The bubbles rapidly
extract and liberate volatile compounds from the sample. The gaseous
effluent is then immediately transferred to a detector (atmospheric
pressure chemical ionization mass spectrometry (MS) or gas chromatography
(GC) hyphenated with MS). ETIE-GC-MS can be used for analysis of volatile
compounds present in real samples. The method was validated for analysis
of selected ethyl esters present in a yogurt drink. The calibration
data set was linear over a range from 5 × 10–7 to 1 × 10–5 M. The limits of detection ranged
from 1.51 × 10–7 to 6.82 × 10–7 M, while the recoveries ranged from 71 to 118%. Inter- and intraday
precision of selected ethyl esters in aqueous solution was satisfactory
(relative standard deviation, 3.6–18.3%). Furthermore, it is
shown that ETIE improves the performance of headspace solid-phase
microextraction while eliminating the need for heating and shaking
samples.