Nano‐liquid chromatography combined with a sustainable microextraction based on natural deep eutectic solvents for analysis of phthalate esters

Abstract

The separation of 11 phthalic acid ester (PAEs) was carried out by nano-liquid chromatography coupled to ultraviolet and MS detection. Preliminary experiments were achieved in order to select suitable stationary phases and chromatographic conditions. The baseline separation was obtained, for all compounds, with an XBridge TM C 18 column in less than 15 min, working in step gradient mode. The sensitivity of the method was improved by on-column focusing. PAEs were extracted from alcoholic and nonalcoholic beverages using vortex-assisted emulsification dispersive liquid-liquid microextration and natural deep eutectic solvents. The whole method was validated in terms of linearity, sensitivity, precision, recovery, and repeatability. Combination of both off-line sample preparation preconcentration and large injection volume led to obtain LOQs in the range 5-47 ng/mL. The developed nano-LC-UV method was extended to MS detection to confirm the presence of PAEs in some beverages commercialized in different types of packaging.

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

“…Moreover, a comparison with previous procedures using DES in DLLME to determine PAEs was also included. The results of such comparison are included in Table S5. − The analytical performance of the developed method, in terms of recovery and limits of quantification (LOQs), was very similar to the previously published results. The recoveries for different methods (i.e., SPE, QuEChERS, LLE, magnetic-SPE, simultaneous distillation extraction, and DLLME) were in the range 55–122%.…”

“…Moreover, only one has employed a NaDES (based on l -menthol and acetic acid), but for the extraction of mineral and tap water and one sparkling apple beverage. These applications − have employed LC-UV as the determination method. The use of MS can reliably confirm the presence of a particular analyte and, thus, the developed method is superior in this regard.…”

“…Although there are no papers about the analysis of PAEs in cold infusions or tonic waters, these kinds of compounds have been previously analyzed in tea leaves, tea infusions, iced-tea, and sparkling soft drinks. For this purpose, different extraction methods such as solid-phase extraction (SPE), , QuEChERS, liquid–liquid extraction (LLE), − and liquid-phase microextraction (LPME) − have been used. Dispersive liquid–liquid microextraction (DLLME), based on the dispersion of an extractant phase on the sample, has been employed several times for the extraction of PAEs from nonalcoholic beverages (using variable volumes of chlorinated and nonchlorinated traditional solvents).…”

Hydrophobic Eutectic Solvent-Based Dispersive Liquid-Liquid Microextraction Applied to the Analysis of Pesticides in Wine

“…On the other hand, the dispersive liquid-liquid microextraction (DLLME), developed by Rezaee et al, in 2006 [9], is recognized for its simplicity, low cost, and high ER. Thus far, DLLME has been applied for the extraction of a wide range of compounds from wine, such as phenols [10], phthalic acid esters [11], mycotoxins [12] and pesticides [13][14][15][16][17][18][19][20][21]. As far as this last category is concerned, to the best of our knowledge, only four methods applied the DLLME by using a green extraction solvent, such as 1-undecanol [14] and 1-octanol [15], or 1-dodecanol [16] and a hydrophobic eutectic solvent based on thymol and octanoic acid [17].…”

MWCNT Buckypaper as Electrochemical Sensing Platform: A Rapid Detection Technology for Phthalic Acid Esters in Solutions*

“…However, most of these methods depict a similar procedure of extracting PAEs from the sample using either a solvent or sorbent-based approach and then analyzing the extracted sample by Gas Chromatography (GC) or High-Performance Liquid Chromatography (HPLC). [4] Though these techniques provide accurate PAEs detection, the complexity, lengthy laboratory procedure, need for experts, use of advanced sample preparation techniques, and inability to perform in-situ and real-time monitoring have left quite a gap in the research field. Therefore, recently more attention has been placed on developing easy to handle, in-situ, and real-time PAEs detection methods.…”