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Cited by 467Ionic liquids properties and applicationsChemical and Physical Properties in Aqueous SolutionsPhase Equilibria and Thermodynamics

Green solvents from ionic liquids and deep eutectic solvents to natural deep eutectic solvents

Open access
Vanda, Henni, Dai, Yuntao, Wilson, Erica G., Verpoorte, Robert, Choi, Young Hae·2018·Comptes Rendus. Chimie
DOI 10.1016/j.crci.2018.04.002
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Abstract

Natural deep eutectic solvents (NADESs) are defined as mixtures of certain molar ratios of natural compounds such as sugars, organic acids, amino acids, and organic bases that are abundant in organisms. The melting points of these mixtures are considerably lower than those of their individual ingredients and far below ambient temperature. The first publications on the NADES concept in 2011 created a great expectation regarding their potential as green solvents that could replace conventional organic solvents in a wide range of applications. This was largely because many of the drawbacks of conventional synthetic ionic liquids (ILs) and deep eutectic solvents (DESs), particularly their toxicity and environmental hazards, could be solved using NADESs. Throughout the last 7 years, the interest in NADESs has increased enormously as reflected by the exponential growth of the number of related publications. The research on NADESs has rapidly expanded particularly into the evaluation of the feasibility of their application in diverse fields such as the extraction of (targeted) bioactive compounds from natural sources, as media for enzymatic or chemical reactions, preservatives of labile compounds, or as vehicles of non–water-soluble compounds for pharmaceutical purposes. Along with the exploration of these potential applications, there have been a large number of other studies related to their physicochemical features, the search for new NADESs, the research into the interactions between NADES components or with solutes, the recovery of solutes from NADES solutions, and the ways of circumventing inherent problems of NADESs such as their high viscosity and the consequent difficulties in handling them. This article contains a review of the applications of NADESs as extraction solvents, reaction media, and preservative, providing also a perspective of their future.

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Crossref · 10.1016/j.crci.2018.04.002

Cites

111 of 111 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

0 of 52 cited sources checked · 0 supported · 0 flagged

  • Interpretationcitation

    High solubility of compounds in NADESs has a positive effect on bioavailability.

    “These reports confirm the high solubility of compounds in NADESs has a positive effect on bioavailability.”
    Quote in the paperSubstantial claim
  • Premisecitation

    With NADES as a cosolvent, the production yield of vanillin from isoeugenol by Lysinibacillus fusiformis increased by 142%.

    “With NADES as a cosolvent, the production yield of vanillin was increased by 142%.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [12] [12] Yang, T.-X.; Zhao, L.-Q.; Wang, J.; Song, G.-L.; Liu, H.-M.; Cheng, H.; Yang, Z. ACS Sustain. Chem. Eng., 5 (2017), pp. 5713-5722 source

      Not checked in the free run.

  • Premisecitation

    Betaine-based NADESs give better results than choline chloride-based NADESs in enzymatic reactions.

    “However, as in the previous example, better results have been achieved with betaine than with choline chloride-based NADESs [11].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [11] [11] Khodaverdian, S.; Dabirmanesh, B.; Heydari, A.; Dashtban-moghadam, E.; Khajeh, K.; Ghazi, F. Int. J. Biol. Macromol., 107 (2018), pp. 2574-2579 source

      Not checked in the free run.

  • Premisecitation

    Enzymatic hydrolysis of the NADES-pretreated rice straw gave a saccharification efficiency of 36.0 ± 3.2%.

    “The subsequent enzymatic hydrolysis of this biomass showed a saccharification efficiency of 36.0 ± 3.2% as evaluated by both FTIR and HPLC analysis [14].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [14] [14] Kumar, A.K.; Parikh, B.S.; Pravakar, M. Environ. Sci. Pollut. Res., 23 (2016), pp. 9265-9275 source

      Not checked in the free run.

  • Interpretationcitation

    These low-cytotoxicity NADESs are good candidates for green extraction solvents in food, cosmetics, and pharmaceutical industry.

    “The tested NADESs exhibited low cytotoxicity, making them good candidates for green extraction solvents in novel applications in the food, cosmetics and pharmaceutical industry [93].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [93] [93] Radošević, K.; Ćurko, N.; Srček, V.G.; Bubalo, M.C.; Tomašević, M.; Ganić, K.K.; Redovniković, I.R. LWT-Food Sci. Technol., 73 (2016), pp. 45-51 source

      Not checked in the free run.

  • May combine two claims. 22
  • The quote only partly states this claim. 2
  • Classified as probably not a substantial claim. 9

  • May combine two claims. The quote only partly states this claim.

    Premisecitation

    In toxicity tests, choline chloride:glucose and choline chloride:glycerol NADESs showed low in vitro toxicity (EC50 >10 mM) and were nontoxic to wheat seed germination (EC50 >5000 mg/L), whereas choline chloride:oxalic acid showed moderate cytotoxicity (EC50 1.64 and 4.19 mM for fish and human cell lines).

    “The data obtained with the in vitro toxicity test on cell lines indicated a low toxicity for choline chloride:glucose and choline chloride:glycerol (EC 50 >10 mM for both cell lines), whereas moderate cytotoxicity was observed for choline chloride:oxalic acid (EC 50 value 1.64 and 4.19 mM for fish and human cell line, respectively).”
    • Also stated in: § 3. Concept of NADESs and their applications · plain
      “The phytotoxicity tests showed that the tested NADESs were nontoxic for seed germination (EC 50 >5000 mg/L) [92].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [92] [92] Radošević, K.; Bubalo, M.C.; Srček, V.G.; Grgas, D.; Dragičević, T.L.; Redovniković, I.R. Ecotoxicol. Environ. Saf., 112 (2015), pp. 46-53 source

      Not checked in the free run.

  • The quote only partly states this claim.

    Premisecitation

    The tested tailor-made NADESs exhibited low cytotoxicity in MCF-7 and HeLa cell lines.

    “The cytotoxicity of a few tailor-made NADESs was also tested with in vitro assays using two human cell lines (MCF-7 and HeLa).”
    • Also stated in: § 3. Concept of NADESs and their applications · plain
      “The tested NADESs exhibited low cytotoxicity”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [93] [93] Radošević, K.; Ćurko, N.; Srček, V.G.; Bubalo, M.C.; Tomašević, M.; Ganić, K.K.; Redovniković, I.R. LWT-Food Sci. Technol., 73 (2016), pp. 45-51 source

      Not checked in the free run.

  • Classified as probably not a substantial claim.

    Premisecitation

    NADESs are mixtures of natural compounds (organic acids/bases, amino acids, sugars, sugar alcohols, polyalcohols) that interact via hydrogen bonding and liquefy at specific molar ratios.

    “Natural deep eutectic solvents (NADESs) are mixtures of natural compounds, namely, organic acids and bases, amino acids, sugars, sugar alcohols, and polyalcohols that interact through hydrogen bonding and liquefy if combined in specific molar ratios.”
    • Also stated in: § Abstract · plain
      “Natural deep eutectic solvents (NADESs) are defined as mixtures of certain molar ratios of natural compounds such as sugars, organic acids, amino acids, and organic bases that are abundant in organisms.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [1] [1] Choi, Y.H.; van Spronsen, J.; Dai, Y.; Verberne, M.; Hollmann, F.; Arends, I.W.C.E.; Witkamp, G.-J.; Verpoorte, R. Plant Physiol., 156 (2011), pp. 1701-1705 source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based). May combine two claims.

    Interpretationreasoning

    The term NADES implies the presence of different levels of water in NADESs, which strongly affect their physical-chemical properties.

    “Among other features this implies, in our view, the presence of different levels of water in NADESs, which strongly affect the physicalechemical properties of the NADES.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    Dilute fructose:citric acid gave the best gluten solubilization, and citric acid could prevent gluten oxidation.

    “The results demonstrated that gluten was best solubilized in dilute fructose:citric acid with the additional advantage that citric acid could prevent gluten oxidation.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [98] [98] Lores, H.; Romero, V.; Costas, I.; Bendicho, C.; Lavilla, I. Talanta, 162 (2017), pp. 453-459 source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    In enzymatic reactions, the common NADES components are choline chloride, betaine, sugar alcohols, and sugars, which raise yield and enzyme stability relative to organic acids.

    “Choline chloride, betaine, sugar alcohol, and sugars are the NADES components that are usually used in enzymatic reactions because they increase the yield and the enzyme stability, as compared to other components such as organic acids [12].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [12] [12] Yang, T.-X.; Zhao, L.-Q.; Wang, J.; Song, G.-L.; Liu, H.-M.; Cheng, H.; Yang, Z. ACS Sustain. Chem. Eng., 5 (2017), pp. 5713-5722 source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Most DESs are biodegradable, nonreactive with water, and usually have acceptable toxicity profiles, unlike most ILs.

    “Most DESs are also biodegradable, nonreactive with water, but unlike most ILs, these solvents usually have acceptable toxicity profiles.”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites [2] [2] Dai, Y.; van Spronsen, J.; Witkamp, G.-J.; Verpoorte, R.; Choi, Y.H. Anal. Chim. Acta, 766 (2013), pp. 61-68 source

      Not checked in the free run.

    • cites [61] [61] Abbott, A.P.; Boothby, D.; Capper, G.; Davies, D.L.; Rasheed, R.K. J. Am. Chem. Soc., 126 (2004), pp. 9142-9147 source

      Not checked in the free run.

    • cites [65] [65] Zhang, Q.; De Oliveira Vigier, K.; Royer, S.; Jérôme, F. Chem. Soc. Rev., 41 (2012), pp. 7108-7146 source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    More than 150 NADES combinations have been proposed.

    “So far, different researchers have proposed more than 150 NADES combinations [2e6].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [2e6]

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    NADESs have been applied in diverse chemical processes, including extraction of natural ingredients, as media for enzymatic/chemical reactions, to solubilize macromolecules and drugs, in cosmetics, and agrochemicals.

    “Following the first publications on NADESs, they have been actively applied in diverse chemical processes, especially in the extraction of natural ingredients [4,7e9], as media for enzymatic or chemical reactions [10e13], to solubilize macromolecules such as polysaccharides and lignins [14] or nonewater-soluble drugs for pharmaceutical purposes [15 e17]”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites [4,7e9]

      Not checked in the free run.

    • cites [10e13]

      Not checked in the free run.

    • cites [15 e17]

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    NADESs made from proline-glutamic acid at a 2:1 ratio and proline-choline chloride at a 1:1 ratio efficiently dissolved rutin.

    “Faggian et al. [101] reported that NADESs composed of prolineeglutamic acid (2:1) and prolineecholine chloride (1:1) efficiently dissolved rutin, a flavonoid used as a nutraceutical for its health-promoting activity.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [101] [101] Faggian, M.; Sut, S.; Perissutti, B.; Baldan, V.; Grabnar, I.; Dall'Acqua, S. Molecules, 21 (2016), pp. 1531-1542 source

      Not checked in the free run.

  • Classified as probably not a substantial claim.

    Premisereasoning

    What distinguishes NADESs from other DESs made of natural ingredients is that the latter do not necessarily have a biological and physiological role in living organisms.

    “However, what distinguishes NADESs from other DESs made of natural ingredients, such as low-melting mixtures, low transition temperature mixtures, and bio-ILs, is that the latter do not necessarily have a biological and physiological role in living organisms.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Interpretationreasoning

    Because their components are natural, NADESs are less toxic and more environmentally friendly than synthetic ILs and DESs.

    “The natural origin of the components (mainly plant primary metabolites, which are taken daily from vegetables or fruit) gives NADESs a great edge over synthetic ionic liquids (ILs) and deep eutectic solvents (DESs), because they are clearly less toxic and more environmentally friendly.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    NADESs have been proposed as an alternative to ILs/DESs because their ingredients come from nature and they are believed to have a real physiological or biological role in nature.

    “Natural DESs or ILs, known as NADESs, have been proposed as a different alternative for two reasons: their ingredients are sourced from nature and they are believed to have a real physiological or biological role in nature.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [1] [1] Choi, Y.H.; van Spronsen, J.; Dai, Y.; Verberne, M.; Hollmann, F.; Arends, I.W.C.E.; Witkamp, G.-J.; Verpoorte, R. Plant Physiol., 156 (2011), pp. 1701-1705 source

      Not checked in the free run.

  • May combine two claims.

    Interpretationreasoning

    High viscosity and virtually no vapor pressure prevail in NADESs, causing challenges for analysis of NADES extracts.

    “The mentioned drawbacks of ILs and DESs, that is, high viscosity and virtually no vapor pressure prevail in NADESs, resulting in some challenges for the analysis of NADES extracts in certain cases.”
    Quote in the paperSubstantial claim

  • Classified as probably not a substantial claim.

    Interpretationnone given

    NADESs have diverse applications including extraction, enzymatic reaction media, dissolution of non-water-soluble compounds, and delivery systems or media for drugs and cosmetics.

    “The diverse applications of NADESs include extraction, enzymatic reaction media, dissolution of nonewater-soluble compounds, and a delivery system or media for drugs and cosmetics, among others”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Interpretationreasoning

    Traditional medicine systems that mix sugar-rich plants with bioactive plants resemble NADESs, implying the NADES concept has been used inadvertently for a long time.

    “There are many examples that seem to bear a great similarity with NADESs such as mixing sugar-rich plants (Glycyrrhiza glabra roots or honey) with bioactive plants.This would imply that inadvertently, the NADES concept has been used for a long time in traditional medicine systems.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    Drought, desiccation, and cold resistance are always connected with high levels of osmolytes, and osmolytes include all compounds found to form NADESs.

    “For example, drought, desiccation, and cold resistance are always reported to be connected with a high level of osmolytes.Osmolytes encompass all the compounds found to form NADESs [1].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [1] [1] Choi, Y.H.; van Spronsen, J.; Dai, Y.; Verberne, M.; Hollmann, F.; Arends, I.W.C.E.; Witkamp, G.-J.; Verpoorte, R. Plant Physiol., 156 (2011), pp. 1701-1705 source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S4 (based).

    Interpretationnone given

    For large-scale processes, the challenge is handling highly viscous nonvolatile solutions of pure compounds or extracts.

    “For large-scale processes, the challenge is how to deal with highly viscous nonvolatile solutions of pure compounds or extracts.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationnone given

    Advantages of NADESs include selectivity for all kinds of compounds, especially medium-polarity compounds; virtual zero vapor pressure; low flammability; low toxicity; increased compound stability; and environmental safety.

    “Summarizing the properties of NADESs, the advantages are their selectivity as solvents for all kinds of compounds, particularly of medium polarity, which are often difficult to dissolve; a virtual zero vapor pressure, which means no losses through evaporation, and low flammability; low toxicity, which allows application in food, cosmetics, agrochemicals, and medicines; increased stability of comp”
    Quote in the paperSubstantial claim
    • Rests on an assumption: NADES components are safe, nontoxic, and edible.

  • May combine two claims.

    Premisecitation

    A 1,2-propanediol-choline chloride-water combination increased salsalate solubility in T37i cell culture medium, allowing a full dose-response curve.

    “Rozema et al. [82] found that a combination of 1,2-propanediolecholine chlorideewater increased the solubility of salsalate in cell culture medium (T37i) allowing the assay of a full doseeresponse curve.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [82] [82] Rozema, E.; Van Dam, A.D.; Sips, H.C.M.; Verpoorte, R.; Meijer, O.C.; Kooijman, S.; Choi, Y.H. RSC Adv., 5 (2015), pp. 61398-61401 source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    In barley seed aleurone tissue, sucrose and choline were the major low-mass molecules and were present in approximately equimolar amounts.

    “In one case, the analysis of the aleurone tissue of barley seeds (Hordeum vulgare) by 1 H NMR spectroscopy showed that the major low mass molecules were sucrose and choline and that they were present in approximately equimolar amounts.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [1] [1] Choi, Y.H.; van Spronsen, J.; Dai, Y.; Verberne, M.; Hollmann, F.; Arends, I.W.C.E.; Witkamp, G.-J.; Verpoorte, R. Plant Physiol., 156 (2011), pp. 1701-1705 source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Betaine monohydrate-glycerol (1:8) was the most selective NADES for palm oil deacidification, with a palmitic acid distribution coefficient of 0.52 (g/L)(g/L)-1 and the lowest antioxidant distribution coefficient.

    “The combination of betaine monohydrateeglycerol (1:8) was the most selective with a distribution coefficient of palmitic acid of 0.52 (g/L)(g/L) À1 and the lowest distribution coefficient of antioxidants, as observed by HPLC and NMR [20].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [20] [20] Zahrina, I.; Nasikin, M.; Krisanti, E.; Mulia, K. Food Chem., 240 (2018), pp. 490-495 source

      Not checked in the free run.

  • May combine two claims.

    Interpretationreasoning

    If pure compounds are to be isolated from NADES extracts, novel methods may be needed to eliminate the solvent because it cannot be evaporated.

    “If pure compounds are to be isolated from NADES extracts, in some cases it is necessary to find novel methods to eliminate the solvent as it cannot be evaporated.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S4 (based). May combine two claims.

    Interpretationreasoning

    NADESs have a biological role in nature and promising potential for biotechnology or biological engineering.

    “Finally, considering the distinctive characteristics of NADESs, that is, their biological role in nature, their potential for a large number of applications in biotechnology or biological engineering is extremely promising.”
    Quote in the paperNot a substantial claim
    • The authors state this as an assumption: NADESs exist as a third liquid phase in cells of all organisms.

  • May combine two claims.

    Premisenone given

    All NADESs are made of hydrophilic or polar ingredients, which theoretically limits their application to hydrophilic compounds.

    “All NADESs are made of hydrophilic or polar ingredients, a fact that should theoretically limit their application to hydrophilic compounds.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationreasoning

    NADES extracts have been mainly analyzed using HPLC-DAD, which detects only compounds with UV/vis chromophores because other HPLC detectors may be incompatible with NADES components.

    “So far, NADES extracts have been mainly analyzed using HPLC-DAD, a method that allows only the detection of compounds with UV/vis chromophore because other available HPLC detectors could be incompatible with NADES components.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S4 (based). May combine two claims.

    Interpretationnone given

    NADESs are cheap, safe, nontoxic, environmentally friendly, and sustainable.

    “which are cheap, safe, nontoxic, environmentally friendly, and sustainable.”
    Quote in the paperNot a substantial claim
    • Rests on an assumption: NADES components are safe, nontoxic, and edible.

  • May combine two claims.

    Premisecitation

    Water content significantly affects the solubilizing capacity of NADESs and reduces their viscosity.

    “This is in line with the experimental data obtained related to the water content of NADESs that showed its significant effect on their solubilizing capacity and the reduction of their viscosity [2,94].”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [2] [2] Dai, Y.; van Spronsen, J.; Witkamp, G.-J.; Verpoorte, R.; Choi, Y.H. Anal. Chim. Acta, 766 (2013), pp. 61-68 source

      Not checked in the free run.

    • cites [94] [94] Dai, Y.; Verpoorte, R.; Choi, Y.H. Food Chem., 159 (2014), pp. 116-121 source

      Not checked in the free run.

28 of 28

  • The paper relies on this without support.

    ILs and DESs have toxicity and environmental hazards that NADESs can solve.

    “This was largely because many of the drawbacks of conventional synthetic ionic liquids (ILs) and deep eutectic solvents (DESs), particularly their toxicity and environmental hazards, could be solved using NADESs.”

  • The paper relies on this without support.

    NADESs have a real physiological or biological role in living organisms.

    “Natural DESs or ILs, known as NADESs, have been proposed as a different alternative for two reasons: their ingredients are sourced from nature and they are believed to have a real physiological or biological role in nature.”

  • The paper relies on this without support.

    NADES components are safe, nontoxic, and edible.

    “As mentioned above, the fact that NADES components are safe, nontoxic, and even edible, allows NADESs to be considered for pharmaceutical, cosmetic, and food applications”

  • The paper relies on this without support.

    NADESs can dissociate in contact with biofluids, allowing dissolved compounds to precipitate.

    “However, before considering NADESs as drug delivery systems, it is important to bear in mind that they might dissociate in contact with biofluids.Thus, even if a compound was totally dissolved in an NADES, it could precipitate when the NADES dissociates in the organism.”

  • The paper relies on this without support.

    NADESs have lower reactivity than ILs.

    “considering the low reactivity of NADESs compared to that of ILs.”

  • The authors state this as an assumption.

    NADESs exist as a third liquid phase in cells of all organisms.

    “In our first article [1], we introduced the hypothesis of NADESs as a third liquid phase in cells of all organisms, presenting indirect evidence for their presence in plants.”
6 of 6

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

  • The development of HDES is a major breakthrough in analytical chemistry.

    “The development of HDES is a major breakthrough in analytical chemistry since DES and NADES are theoretically and practically limited to the extraction of only hydrophilic or polar compounds [48].”

    From Recent Advances in Hydrophobic Deep Eutectic Solvents for Extraction (2019) · cites this paper as [48]

  • NADES can be used as solubilization agents for macromolecules and as media for enzymatic reactions.

    “NADES can be used as solubilization agents for macromolecules and as media for enzymatic reactions [48].”

    From Recent Advances in Hydrophobic Deep Eutectic Solvents for Extraction (2019) · cites this paper as [48]

  • DES and NADES are theoretically and practically limited to the extraction of only hydrophilic or polar compounds.

    “The development of HDES is a major breakthrough in analytical chemistry since DES and NADES are theoretically and practically limited to the extraction of only hydrophilic or polar compounds [48].”

    From Recent Advances in Hydrophobic Deep Eutectic Solvents for Extraction (2019) · cites this paper as [48]

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • The berberine solvent ratios differ between the text and Table 4

    Minor

    The text gives 2:1 ratios for both proline-malic acid and proline-urea, while Table 4 gives 1:1 for both formulations.

1 of 1

Cites

Flagged first, then by citations

2 of the 113 references couldn’t be matched to a known paper.

Research works printed but not linked: 4

  1. [5] Bakirtzi, C.; Triantafyllidou, K.; Makris, D.P. J. App. Res. Med. Aromat. Plants, 3 (2016), pp. 120-127
  2. [22] Walden, P. Bull. Acad. Imper. Sci. (St. Petersburg), 8 (1914), pp. 405-422
  3. [23] Hückel, W. Chem. Ber., 91 (1958) (XIX–LXVI)
  4. [78] Wang, A.L.; Zheng, X.L.; Zhao, Z.Z.; Li, C.P.; Zheng, X.F. Prog. Chem., 26 (2014), pp. 784-795

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Related

Authors
Vanda, H., Dai, Y., Wilson, E. G., Verpoorte, R., & Choi, Y. H.
Affiliations
  • Leiden University (NL)
  • China Academy of Chinese Medical Sciences (CN)
Corresponding author
Choi, Young Hae
ORCID
Venue
Comptes Rendus. Chimie
Publisher
MathDoc/Centre Mersenne
Published
2018-05-10
Volume
21
Issue
6
Pages
628-638
ISSN
  • 1631-0748 (ISSN-L)
  • 1878-1543
DOI
10.1016/j.crci.2018.04.002
OpenAlex
W2799658069
Cited by
467
References
113
Citations by year
2026: 37 · 2025: 70 · 2024: 65 · 2023: 72 · 2022: 59 · 2021: 72 · 2020: 51 · 2019: 39 · 2018: 2
FWCI
9.82
Type
journal article
Language
en
Open access
Licence
www.elsevier.com/tdm/userlicense/1.0/ (tdm)
Locations
  • Comptes Rendus Chimie (publishedVersion)
  • Leiden Repository (Leiden University) (submittedVersion)
  • Comptes Rendus Chimie (submittedVersion)
  • Data Archiving and Networked Services (DANS) (submittedVersion)
Topics
  • Physical Sciences › Chemical Engineering › Catalysis › Ionic liquids properties and applications
  • Physical Sciences › Chemical Engineering › Filtration and Separation › Chemical and Physical Properties in Aqueous Solutions
  • Physical Sciences › Engineering › Biomedical Engineering › Phase Equilibria and Thermodynamics
Keywords
natural deep eutectic solvents, green solvents, ionic liquids, deep eutectic solvents, solvent toxicity, bioactive compound extraction, reaction media, pharmaceutical vehicles, viscosity, physicochemical properties, solute recovery

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