Development of a
Green Alternative Vortex-Assisted
Dispersive Liquid–Liquid Microextraction Based on Natural Hydrophobic
Deep Eutectic Solvents for the Analysis of Phthalate Esters in Soft
Drinks
posted on 2021-01-20, 16:34authored byÁlvaro Santana-Mayor, Antonio V. Herrera-Herrera, Ruth Rodríguez-Ramos, Bárbara Socas-Rodríguez, Miguel Ángel Rodríguez-Delgado
A new green alternative vortex-assisted
dispersive liquid–liquid
microextraction method based on a natural hydrophobic deep eutectic
solvent was developed for the extraction of 14 phthalic acid esters
and one adipate in cold infusions and tonic waters. Analyses were
carried out using ultra-performance liquid chromatography coupled
to tandem mass spectrometry. Different eutectic mixtures based on
the monoterpene thymol (essential oil of thyme) and medium-chain fatty
acids (octanoic and decanoic acids) at different molar ratios were
tested in this regard. The effect of different factors affecting extraction
efficiency was optimized through a systematic approach. The method
was validated by means of precision, matrix-matched calibration, recovery,
and repeatability studies using two different deuterated surrogate
standards (dibutyl phthalate-3,4,5,6-d4 and dihexyl phthalate-3,4,5,6-d4). The
method proved to be linear (determination coefficients were higher
than 0.9912) with normalized recoveries in the range between 71 and
124% (except for di-n-octyl phthalate at a low concentration
level in tonic water [63%]). Then, the method was applied for the
analysis of the selected compounds in 3 pineapple/green tea-based
cold infusions and 8 tonic beverages. Finally, the greenness of the
procedure was assessed using the Analytical Eco-Scale. This paper
represents the first application of this natural hydrophobic deep
eutectic solvent for the analysis of phthalate esters, and, also the
first time, these compounds are analyzed in cold infusion and tonic
water.