## 4 Supramolecular Solvent (SUPRAS) as Extraction Phase  
Supramolecular solvents (SUPRASs) are nano-structured liquids in which the spontaneous association of different molecules self-organizes in a biphasic system formed by a continuous and a dispersed phase. SUPRASs' amphiphilic nature highlights one of their main advantages, providing excellent solvation for a wide range of organic and inorganic compounds. This characteristic is due to the presence of supramolecular aggregates, promoting a solvent with different degrees of polarity [77; 78; 79]. Supramolecular solvents have already been used in the determination of several classes of compounds such as parabens, pesticides, polycyclic aromatic hydrocarbons and bisphenols [80; 81; 82; 83]. A very recent SUPRAS paper showed SUPRAS applicability with LPME as the extraction solvent. In this work, cationic surfactants didodecyldimethylammonium bromide (DDAB) and dodecyltrimethylammonium bromide (DTAB) were used in the extraction solvent mixture. SUPRAS-based liquid phase microextraction (SUPRAS-LPME) was also used in the preconcentration of five TCs (tetracycline, oxytetracycline, chlortetracycline, methacycline and doxycycline) in milk, egg and honey samples. An alkaline solution of the analytes was preconcentrated via electrostatic and hydrophobic interactions in the presence of the SUPRAS extraction solvent. The extraction mechanism was confirmed by the exploration of SUPRAS' Zeta potential and particle size. According to the authors, the results showed an excellent quantification method using SUPRAS and LPME for the determination of TCs in various matrices [84]. Recently, an innovative study proposed the application of a novel hexafluoroisopropanol (HFIP)/Brij-35 based SUPRAS in the determination of some organic compounds in water samples also using LPME. Brij-35 is a budget-friendly and non-toxic anionic surfactant that has a high cloud point (>100 \({}^{\circ}\)C). Presenting characteristics of a strong hydrogen-bond donor, elevated density and high hydrophobicity, HFIP was used in Brij-35's density regulation and cloud-point reduction to \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Technique** & **DES/NADES Composition** & **Analytes** & **Matrix** & **LOD** & **Instrumentation** & **Ref.** \\ \hline DES-ALLME & Ch-Cl: TNO 1 & Methadone & Water and biologic & 0.7 ug L\({}^{-1}\) & GC-FID & [65] \\ \hline UA-DLIME & trioctylmethylammonium & & & & & \\ chloride: decanoic acid & UV filters & Water & 0.15–0.30 ng mL\({}^{-1}\) & HFLC-UV & [66] \\ \hline VA-LLME & Decanoic acid: & Malondialdehydedehyde (MDA) and & Human urine, apple juice and & 2.0 and 10 mg mL\({}^{-1}\) & HFLC-UV & [67] \\  & bromide & Formaldehyde (FA) & rain water & 2.0 and 10 mg mL\({}^{-1}\) & HFLC-UV & [67] \\ \hline AA-EME & ChCl: Ph-EOH & Amphetamine-type & and & & & \\ stimulants (Ats) & & pharmaceutical & 2.0–5.0 ng mL\({}^{-1}\) & HFLC-UV & [68] \\  & & & wastewater & & & \\ \hline SFO-ALLME & Ch-Cl n-butylric acid & Aromatic amines & Aqueous samples & 1.8–6.0 ng L\({}^{-1}\) & GC-MS & [69] \\ \hline UA-DLIME & thymol, acamophor, decanoic & PAHs & Industrial effluents & 0.0039–0.0098 & & \\  & 10-undacycline acids & & & & & \\  & & & & & \\ \hline DSPE-DES-ALLMEhCl: 4-chlorophenyl & Tricyclic & Human urine & 8–15 and 32–60 & GC-MS & [71] \\  & & antidepressant drugs & and plasma & ng L\({}^{-1}\) & \\ \hline DES-GALIME & Mixture of two or three & & & & \\  & different carboxylic acids (CS, ChCl, CII and CII) & & & & \\ \hline VA-RF-LIME & [N4444]/Cl TBA 2: ethylene glycol (EG) & & & & \\  & & & & & \\ \hline MA-in & ChCl: phenol and ChCl: syringe & & & & \\  & butyric acid & & & & \\ \hline DLME & Hexafluoro isopropanol: & & & & \\  & & & & & \\  & & & & & \\ \hline UA-DLIME-DES & Quaternary phosphonium & & & & \\  & salts: straight-chain & & & & \\  & monobasic acids & & & & \\ \hline \hline \end{tabular}  
* 1–5, 6, 7, 8-Tetrahydro-5, 5, 8, 8-tetramethylnphthalene-2-ol; 2—tetrabutylammonium chloride ([N4444] CI, TBA).  
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