Deep Eutectic Solvent Based Air Assisted Ligandless Emulsification Liquid–Liquid Microextraction for Preconcentration of Some Heavy Metals in Biological and Environmental Samples

Recent Applications of Deep Eutectic Solvents in Environmental Analysis

“…Although most applications of DESs in environmental samples analysis have mainly been focused on the evaluation of organic contaminants, the study of inorganic species has also been carried out (see Table 2 [27][28][29][30][31][32][33][34][35][36][37][38][39][40][41]). In this regard, heavy metals such as copper [29,35], lead [27,29,35,40], tungsten [28], arsenic [28,31,37,38], cadmium [27,35,40], cobalt [27], nickel [27,33,35], palladium [34,35], antimony [31,37], mercury [30], and chromium [37,41] represent the main applications of DESs to the analysis of inorganic species, but also trace elements like molybdenum [37], selenium [37,39], and vanadium [37], and compounds including ammonia [36], metal oxides …”

“…In this regard, heavy metals such as copper [29,35], lead [27,29,35,40], tungsten [28], arsenic [28,31,37,38], cadmium [27,35,40], cobalt [27], nickel [27,33,35], palladium [34,35], antimony [31,37], mercury [30], and chromium [37,41] represent the main applications of DESs to the analysis of inorganic species, but also trace elements like molybdenum [37], selenium [37,39], and vanadium [37], and compounds including ammonia [36], metal oxides [32], chlorides [32], acetates [32], phosphates [32], sulphates [32], and carbonates [32] have been studied. Regarding the matrices evaluated, the analysis of environmental waters stands out and different types of waters have been analysed [27,[29][30][31][33][34][35][36][38]…”

“…-The method was applied to the analysis of real samples. [41] With this aim, both NaDESs [29][30][31][32]37,40] or non-NaDESs [27,28,[32][33][34][35][36]38,39,41] have been used for the analysis of inorganic species in environmental samples. Regarding their aqueous compatibility, most cases imply the use of hydrophilic DESs [28][29][30][31][32][34][35][36][37][38][39][40][41] even though some examples of quasi-HDESs [33] and HDESs [27] can be found in the literature.…”

“…[41] With this aim, both NaDESs [29][30][31][32]37,40] or non-NaDESs [27,28,[32][33][34][35][36]38,39,41] have been used for the analysis of inorganic species in environmental samples. Regarding their aqueous compatibility, most cases imply the use of hydrophilic DESs [28][29][30][31][32][34][35][36][37][38][39][40][41] even though some examples of quasi-HDESs [33] and HDESs [27] can be found in the literature. As it is shown in Table 2, ChCl constitutes the most used HBA [28,29,31,32,[34][35][36][37][38][39][40][41], although other quaternary salts such as trihexyl(tetradecyl)phosphonium chloride (THT-DPC) [27] or TBAC [33], a...…”

“…Regarding their aqueous compatibility, most cases imply the use of hydrophilic DESs [28][29][30][31][32][34][35][36][37][38][39][40][41] even though some examples of quasi-HDESs [33] and HDESs [27] can be found in the literature. As it is shown in Table 2, ChCl constitutes the most used HBA [28,29,31,32,[34][35][36][37][38][39][40][41], although other quaternary salts such as trihexyl(tetradecyl)phosphonium chloride (THT-DPC) [27] or TBAC [33], as well as N,N -dimethyl urea (DMU) [32], or betaine [30] have also been employed. With respect to the HBDs, different alcohols [30,32,[34][35][36]38,39,41] and organic acids [27,28,31,32,37], as well as urea [29,…”