Open Access Review

Natural Deep Eutectic Solvents: A New Environment Friendly Solvent

Authors

  • Saurabh Kumar Tiwari

    Department of Chemistry, Kanhaiyalal Basantlal Postgraduate College (KBPG), Mirzapur 231001, India

  • Pratibha Yadav

    Department of Chemistry, Ewing Christian College, Prayagraj 211003, India

  • Mrigank Mauli Dwivedi

    The National Centre of Experimental Mineralogy and Petrology (NCEMP), University of Allahabad, Prayagraj 211002, India

  • Kamlesh Pandey

    The National Centre of Experimental Mineralogy and Petrology (NCEMP), University of Allahabad, Prayagraj 211002, India

DOI:

https://doi.org/10.55121/nefm.v5i1.1182
Received: 28 February 2026 | Revised: 26 March 2026 | Accepted: 7 April 2026 | Published Online: 14 April 2026

Abstract

The fabrication of materials and chemical synthesis depend substantially on solvents. They are strategic part of the green chemistry framework. In accordance with green chemistry, solvents need to qualify certain parameters, such as biodegradability, non-toxicity, non-flammability, recyclability & reusability, low cost etc. to be termed as green solvents. Deep eutectic solvents (DESs) are emerging as excellent “designer” alternatives to conventional solvents owing along with the above mentioned eco-friendly properties have exceptional thermal, moisture durability and best tunable features. DESs have a crucial role in several field related to chemical synthesis along with catalysis, material extraction and purification. They serve an array of roles as solvents, monomers, and templating agents. The Deep Eutectic Solvent (DES)-based electrodeposition opens a new era of the development of metal, alloy, and metallic nanocomposite coatings with highly tailored properties. The corrosion resistance of these coatings is multifactorial, dictated by the DES composition, metal ion concentration, and precise electrochemical parameters. The Electrolytes based on DES are also useful and inexpensive replacements for traditional corrosive and environmentally hazardous aqueous acid solutions for metal alloy electropolishing. In this current review, we are providing an overview of recent research on DES in polymer synthesis and material fabrication.

Keywords

Deep Eutectic Solvent, Green Solvent, Polymerization, Electropolishing, Organic Synthesis

References

[1] Anastas, P.T., Warner, J.C., 2000. Green Chemistry: Theory and Practice. Oxford University Press: Oxford, UK. DOI: https://doi.org/10.1093/oso/9780198506980.001.0001

[2] Anastas, P.T., Williamson, T.C., 1996. Green Chemistry: Designing Chemistry for the Environment. American Chemical Society: Washington, DC, USA. p. 626.

[3] Nandihalli, N., Gregory, D.H., Mori, T., 2022. Energy-Saving Pathways for Thermoelectric Nanomaterial Synthesis: Hydrothermal/Solvothermal, Microwave-Assisted, Solution-Based, and Powder Processing. Advanced Science. 9(25), 2106052. DOI: https://doi.org/10.1002/advs.202106052

[4] Henderson, R.K., Jiménez-González, C., Constable, D.J.C., et al., 2011. Expanding GSK's Solvent Selection Guide—Embedding Sustainability into Solvent Selection Starting at Medicinal Chemistry. Green Chemistry. 13(4), 854–862. DOI: https://doi.org/10.1039/c0gc00918k

[5] Prat, D., Wells, A., Hayler, J., et al., 2016. CHEM21 Selection Guide of Classical- and Less Classical-Solvents. Green Chemistry. 18, 288–296. DOI: https://doi.org/10.1039/C5GC01008J

[6] Verma, A., Srivastava, A., Tiwari, S.K., et al., 2020. Visible Light Promoted Formation of N–S Bond by Photocatalyst Eosin Y. Journal of Heterocyclic Chemistry. 57(9), 3493–3498. DOI: https://doi.org/10.1002/jhet.4069

[7] Tiwari, S.K., Shivhare, K.N., Patel, M.K., et al., 2022. A Metal Free, Hantzsch Synthesis for Privileged Scaffold 1,4-Dihydropyridines: A Glycerol Promoted Sustainable Protocol. Polycyclic Aromatic Compounds. 42(4), 1035–1047. DOI: https://doi.org/10.1080/10406638.2020.1764988

[8] Abbott, A.P., Capper, G., Davies, D.L., et al., 2003. Novel Solvent Properties of Choline Chloride/Urea Mixtures. Chemical Communications. 1, 70–71. DOI: https://doi.org/10.1039/b210714g

[9] Abbott, A.P., Boothby, D., Capper, G., et al., 2004. Deep Eutectic Solvents Formed between Choline Chloride and Carboxylic Acids: Versatile Alternatives to Ionic Liquids. Journal of the American Chemical Society. 126(29), 9142–9147. DOI: https://doi.org/10.1021/ja048266j

[10] Zhang, Q., De Oliveira Vigier, K., Royer, S., et al., 2012. Deep Eutectic Solvents: Syntheses, Properties and Applications. Chemical Society Reviews. 41(21), 7108–7146. DOI: https://doi.org/10.1039/c2cs35178a

[11] Hansen, B.B., Spittle, S., Chen, B., et al., 2021. Deep Eutectic Solvents: A Review of Fundamentals and Applications. Chemical Reviews. 121(3), 1232–1285. DOI: https://doi.org/10.1021/acs.chemrev.0c00385

[12] Fanjul-Mosteirín, N., Concellón, C., del Amo, V., 2016. L-Isoleucine in a Choline Chloride/Ethylene Glycol Deep Eutectic Solvent: A Reusable Reaction Kit for the Asymmetric Cross-Aldol Carboligation. Organic Letters. 18(17), 4266–4269. DOI: https://doi.org/10.1021/acs.orglett.6b01989

[13] Abranches, D.O., Martins, M.A.R., Silva, L.P., et al., 2019. Phenolic Hydrogen Bond Donors in the Formation of Non-Ionic Deep Eutectic Solvents: The Quest for Type V DES. Chemical Communications. 55(69), 10253–10256. DOI: https://doi.org/10.1039/C9CC04846D

[14] Arriaga, S., Aizpuru, A., 2019. Innovative Non-Aqueous Phases and Partitioning Bioreactor Configurations. Advances in Chemical Engineering. 54, 299–348. DOI: https://doi.org/10.1016/bs.ache.2018.12.004

[15] Suriyanarayanan, S., Olsson, G., Kathiravan, S., et al., 2019. Non-Ionic Deep Eutectic Liquids: Acetamide–Urea Derived Room Temperature Solvents. International Journal of Molecular Sciences. 20(12), 2857. DOI: https://doi.org/10.3390/ijms20122857

[16] Panda, D.K., Bhargava, B.L., 2022. Molecular Dynamics Investigation of Non-Ionic Deep Eutectic Solvents. Journal of Molecular Graphics and Modelling. 113, 108152. DOI: https://doi.org/10.1016/j.jmgm.2022.108152

[17] Lazerges, M., Rietveld, I.B., Corvis, Y., et al., 2010. Thermodynamic Studies of Mixtures for Topical Anesthesia: Lidocaine–Salol Binary Phase Diagram. Thermochimica Acta. 497(1–2), 124–128. DOI: https://doi.org/10.1016/j.tca.2009.08.016

[18] van Osch, D.J.G.P., Dietz, C.H.J.T., van Spronsen, J., et al., 2019. A Search for Natural Hydrophobic Deep Eutectic Solvents Based on Natural Components. ACS Sustainable Chemistry & Engineering. 7(3), 2933–2942. DOI: https://doi.org/10.1021/acssuschemeng.8b03520

[19] Ndizeye, N., Suriyanarayanan, S., Nicholls, I.A., 2019. Polymer Synthesis in Non-Ionic Deep Eutectic Solvents. Polymer Chemistry. 10(39), 5289–5295. DOI: https://doi.org/10.1039/C9PY01039D

[20] Ismail, N., Pan, J., Rahmati, M., et al., 2022. Non-Ionic Deep Eutectic Solvents for Membrane Formation. Journal of Membrane Science. 646, 120238. DOI: https://doi.org/10.1016/j.memsci.2021.120238

[21] Ribeiro, B.D., Florindo, C., Iff, L.C., et al., 2015. Menthol-Based Eutectic Mixtures: Hydrophobic Low Viscosity Solvents. ACS Sustainable Chemistry & Engineering. 3(10), 2469–2477. DOI: https://doi.org/10.1021/acssuschemeng.5b00532

[22] van Osch, D.J.G.P., Dietz, C.H.J.T., Warrag, S.E.E., et al., 2020. The Curious Case of Hydrophobic Deep Eutectic Solvents: A Story on the Discovery, Design, and Applications. ACS Sustainable Chemistry & Engineering. 8(29), 10591–10612. DOI: https://doi.org/10.1021/acssuschemeng.0c00559

[23] Liu, Y., Friesen, J.B., McAlpine, J.B., et al., 2018. Natural Deep Eutectic Solvents: Properties, Applications, and Perspectives. Journal of Natural Products. 81(3), 679–690. DOI: https://doi.org/10.1021/acs.jnatprod.7b00945

[24] Dai, Y., van Spronsen, J., Witkamp, G.-J., et al., 2013. Natural Deep Eutectic Solvents as New Potential Media for Green Technology. Analytica Chimica Acta. 766, 61–68. DOI: https://doi.org/10.1016/j.aca.2012.12.019

[25] van Osch, D.J.G.P., Zubeir, L.F., van den Bruinhorst, A., et al., 2015. Hydrophobic Deep Eutectic Solvents as Water-Immiscible Extractants. Green Chemistry. 17(9), 4518–4521. DOI: https://doi.org/10.1039/C5GC01451D

[26] Florindo, C., Branco, L.C., Marrucho, I.M., 2017. Development of Hydrophobic Deep Eutectic Solvents for Extraction of Pesticides from Aqueous Environments. Fluid Phase Equilibria. 448, 135–142. DOI: https://doi.org/10.1016/j.fluid.2017.04.002

[27] Schaeffer, N., Martins, M.A.R., Neves, C.M.S.S., et al., 2018. Sustainable Hydrophobic Terpene-Based Eutectic Solvents for the Extraction and Separation of Metals. Chemical Communications. 54(58), 8104–8107. DOI: https://doi.org/10.1039/C8CC04152K

[28] Makoś, P., Przyjazny, A., Boczkaj, G., 2018. Hydrophobic Deep Eutectic Solvents as “Green” Extraction Media for Polycyclic Aromatic Hydrocarbons in Aqueous Samples. Journal of Chromatography A. 1570, 28–37. DOI: https://doi.org/10.1016/j.chroma.2018.07.070

[29] van Osch, D.J.G.P., Parmentier, D., Dietz, C.H.J.T., et al., 2016. Removal of Alkali and Transition Metal Ions from Water with Hydrophobic Deep Eutectic Solvents. Chemical Communications. 52(80), 11987–11990. DOI: https://doi.org/10.1039/C6CC06105B

[30] Dietz, C.H.J.T., Kroon, M.C., Di Stefano, M., et al., 2018. Selective Separation of Furfural and Hydroxymethylfurfural from an Aqueous Solution Using a Supported Hydrophobic Deep Eutectic Solvent Liquid Membrane. Faraday Discussions. 206, 77–92. DOI: https://doi.org/10.1039/C7FD00152E

[31] Haider, M.B., Jha, D., Kumar, R., et al., 2020. Ternary Hydrophobic Deep Eutectic Solvents for Carbon Dioxide Absorption. International Journal of Greenhouse Gas Control. 92, 102839. DOI: https://doi.org/10.1016/j.ijggc.2019.102839

[32] Janicka, P., Kaykhaii, M., Płotka-Wasylka, J., et al., 2022. Supramolecular Deep Eutectic Solvents and Their Applications. Green Chemistry. 24(13), 5035–5045. DOI: https://doi.org/10.1039/D2GC00906D

[33] Zhou, P., Liu, G., Fang, H., et al., 2024. Supramolecular Deep Eutectic Solvents: Current Advances and Critical Evaluation of Cyclodextrins from Solute to Solvent in Emerging Functional Food. Comprehensive Reviews in Food Science and Food Safety. 23(6), e70026. DOI: https://doi.org/10.1111/1541-4337.70026

[34] Ioannou, K.A., Ioannou, G.D., Christou, A., et al., 2024. Novel Supramolecular Deep Eutectic Solvent (SUPRADES) as a Sole Chiral Selector in Capillary Electrophoresis for the Enantiomeric Separation of Fluorine-Substituted Amphetamine Analogs. Journal of Chromatography A. 1715, 464628. DOI: https://doi.org/10.1016/j.chroma.2024.464628

[35] Zhang, J., Li, S., Yao, L., et al., 2024. Cyclodextrin-Based Ternary Supramolecular Deep Eutectic Solvents for Efficient Extraction and Analysis of Trace Quinolones and Sulfonamides in Wastewater by Adjusting pH. Analytica Chimica Acta. 1311, 342714. DOI: https://doi.org/10.1016/j.aca.2024.342714

[36] Omar, K.A., Sadeghi, R., 2021. Novel Nonanol-Based Deep Eutectic Solvents: Thermophysical Properties and Their Applications in Liquid-Liquid Extraction and Amino Acid Detection. Journal of Molecular Liquids. 336, 116359. DOI: https://doi.org/10.1016/j.molliq.2021.116359

[37] Sun, P., Wang, C., Li, S., et al., 2024. Supramolecular Deep Eutectic Solvent: A Powerful Tool for Pre-Concentration of Trace Metals in Edible Oil. Analytical and Bioanalytical Chemistry. 416(15), 3533–3542. DOI: https://doi.org/10.1007/s00216-024-05304-x

[38] Florindo, C., Celia-Silva, L.G., Martins, L.F.G., et al., 2018. Supramolecular Hydrogel Based on a Sodium Deep Eutectic Solvent. Chemical Communications. 54(54), 7527–7530. DOI: https://doi.org/10.1039/C8CC03266A

[39] Zhou, M., Fakayode, O.A., Ahmed Yagoub, A.E., et al., 2022. Lignin Fractionation from Lignocellulosic Biomass Using Deep Eutectic Solvents and Its Valorization. Renewable and Sustainable Energy Reviews. 156, 111986. DOI: https://doi.org/10.1016/j.rser.2021.111986

[40] Silva, E., Oliveira, F., Silva, J.M., et al., 2020. Optimal Design of THEDES Based on Perillyl Alcohol and Ibuprofen. Pharmaceutics. 12(11), 1121. DOI: https://doi.org/10.3390/pharmaceutics12111121

[41] Javed, S., Mangla, B., Sultan, M.H., et al., 2024. Pharmaceutical Applications of Therapeutic Deep Eutectic Systems (THEDES) in Maximising Drug Delivery. Heliyon. 10(9), e29783. DOI: https://doi.org/10.1016/j.heliyon.2024.e29783

[42] Kalantri, S., Vora, A., 2024. Eutectic Solutions for Healing: A Comprehensive Review on Therapeutic Deep Eutectic Solvents (TheDES). Drug Development and Industrial Pharmacy. 50(5), 387–400. DOI: https://doi.org/10.1080/03639045.2024.2345131

[43] Álvarez, M.S., Zhang, Y., 2019. Sketching Neoteric Solvents for Boosting Drugs Bioavailability. Journal of Controlled Release. 311–312, 225–232. DOI: https://doi.org/10.1016/j.jconrel.2019.09.008

[44] Stewart, S.A., Domínguez-Robles, J., Donnelly, R.F., et al., 2018. Implantable Polymeric Drug Delivery Devices: Classification, Manufacture, Materials, and Clinical Applications. Polymers. 10(12), 1379. DOI: https://doi.org/10.3390/polym10121379

[45] Tanner, E.E.L., Ibsen, K.N., Mitragotri, S., 2018. Transdermal Insulin Delivery Using Choline-Based Ionic Liquids (CAGE). Journal of Controlled Release. 286, 137–144. DOI: https://doi.org/10.1016/j.jconrel.2018.07.029

[46] Wang, H., Gurau, G., Shamshina, J., et al., 2014. Simultaneous Membrane Transport of Two Active Pharmaceutical Ingredients by Charge Assisted Hydrogen Bond Complex Formation. Chemical Science. 5(9), 3449–3456. DOI: https://doi.org/10.1039/C4SC01036A

[47] Wang, J., Li, M., Duan, L., et al., 2022. Deep Eutectic Systems as Novel Vehicles for Assisting Drug Transdermal Delivery. Pharmaceutics. 14(11), 2265. DOI: https://doi.org/10.3390/pharmaceutics14112265

[48] Shekaari, H., Zafarani-Moattar, M.T., Mokhtarpour, M., 2018. Experimental Determination and Correlation of Acetaminophen Solubility in Aqueous Solutions of Choline Chloride Based Deep Eutectic Solvents at Various Temperatures. Fluid Phase Equilibria. 462, 100–110. DOI: https://doi.org/10.1016/j.fluid.2018.01.017

[49] Mokhtarpour, M., Shekaari, H., Shayanfar, A., 2020. Design and Characterization of Ascorbic Acid Based Therapeutic Deep Eutectic Solvent as a New Ion-Gel for Delivery of Sunitinib Malate. Journal of Drug Delivery Science and Technology. 56, 101512. DOI: https://doi.org/10.1016/j.jddst.2020.101512

[50] Nahar, Y., Thickett, S.C., 2021. Greener, Faster, Stronger: The Benefits of Deep Eutectic Solvents in Polymer and Materials Science. Polymers. 13(3), 447. DOI: https://doi.org/10.3390/polym13030447

[51] Cai, L., Chen, G., Su, B., et al., 2021. 3D Printing of Ultra-Tough, Self-Healing Transparent Conductive Elastomeric Sensors. Chemical Engineering Journal. 426, 130545. DOI: https://doi.org/10.1016/j.cej.2021.130545

[52] Tolmachev, D., Nazarychev, V., Fedotova, V., et al., 2023. Investigation of Structure and Properties of Polymerizable Deep Eutectic Solvent Based on Choline Chloride and Acrylic Acid. Journal of Molecular Liquids. 370, 121030. DOI: https://doi.org/10.1016/j.molliq.2022.121030

[53] Yu, Z., Zhao, Y., Zhao, K., et al., 2024. Recent Advances in Liquid-Free Ionic Conductive Elastomers Based on Polymerizable Deep Eutectic Solvents: Preparations, Properties and Applications. Chemical Engineering Journal. 499, 156113. DOI: https://doi.org/10.1016/j.cej.2024.156113

[54] Fazende, K.F., Gary, D.P., Mota-Morales, J.D., et al., 2020. Kinetic Studies of Photopolymerization of Monomer-Containing Deep Eutectic Solvents. Macromolecular Chemistry and Physics. 221(6), 1900511. DOI: https://doi.org/10.1002/macp.201900511

[55] Isik, M., Ruiperez, F., Sardon, H., et al., 2016. Innovative Poly(Ionic Liquid)s by the Polymerization of Deep Eutectic Monomers. Macromolecular Rapid Communications. 37(14), 1135–1142. DOI: https://doi.org/10.1002/marc.201600026

[56] Ren'ai, L., Zhang, K., Chen, G., et al., 2018. Green Polymerizable Deep Eutectic Solvent (PDES) Type Conductive Paper for Origami 3D Circuits. Chemical Communications. 54(18), 2304–2307. DOI: https://doi.org/10.1039/C7CC09209A

[57] Corrigan, N., Jung, K., Moad, G., et al., 2020. Reversible-deactivation radical polymerization (Controlled/living radical polymerization): From discovery to materials design and applications. Progress in Polymer Science. 111, 101311. DOI: https://doi.org/10.1016/j.progpolymsci.2020.101311

[58] Lee, Y., Boyer, C., Kwon, M.S., 2023. Photocontrolled RAFT Polymerization: Past, Present, and Future. Chemical Society Reviews. 52, 3035−3097. DOI: https://doi.org/10.1039/D1CS00069A

[59] Braunecker, W.A., Matyjaszewski, K., 2007. Controlled/Living Radical Polymerization: Features, Developments, and Perspectives. Progress in Polymer Science. 32(1), 93–146. DOI: https://doi.org/10.1016/j.progpolymsci.2006.11.002

[60] Maximiano, P., Mendonça, P.V., Santos, M.R.E., et al., 2017. Eutectic Mixtures as a Green Alternative for Efficient Catalyst Recycling in Atom Transfer Radical Polymerizations. Journal of Polymer Science Part A: Polymer Chemistry. 55(3), 371–381. DOI: https://doi.org/10.1002/pola.28415

[61] Mendonça, P.V., Lima, M.S., Guliashvili, T., et al., 2017. Deep Eutectic Solvents (DES): Excellent Green Solvents for Rapid SARA ATRP of Biorelevant Hydrophilic Monomers at Ambient Temperature. Polymer. 132, 114–121. DOI: https://doi.org/10.1016/j.polymer.2017.10.060

[62] Quirós-Montes, L., Carriedo, G.A., García-Álvarez, J., et al., 2019. Deep Eutectic Solvents for Cu-Catalysed ARGET ATRP under an Air Atmosphere: A Sustainable and Efficient Route to Poly(methyl methacrylate) Using a Recyclable Cu(II) Metal–Organic Framework. Green Chemistry. 21, 5865–5875. DOI: https://doi.org/10.1039/C9GC02624J

[63] Santha Kumar, A.R.S., Singha, N.K., 2019. RAFT Polymerization of 2-Hydroxyethyl Methacrylate in a Deep Eutectic Solvent. Journal of Polymer Science Part A: Polymer Chemistry. 57(23), 2281–2286. DOI: https://doi.org/10.1002/pola.29527

[64] Chou, Y.-T., Lee, W.-R., Yu, S.-S., 2024. Efficient Synthesis of Ultrahigh Molecular Weight Poly(methyl methacrylate) via Visible Light-Induced RAFT Polymerization in Deep Eutectic Solvent. Macromolecules. 57(19), 9241–9249. DOI: https://doi.org/10.1021/acs.macromol.4c01519

[65] Sánchez-Condado, A., Carriedo, G.A., Presa Soto, A., et al., 2019. Organolithium-Initiated Polymerization of Olefins in Deep Eutectic Solvents under Aerobic Conditions. ChemSusChem. 12(13), 3134–3143. DOI: https://doi.org/10.1002/cssc.201900533

[66] Altundağ, A., Ünlü, A.E., Takaç, S., 2021. Deep Eutectic Solvent-Assisted Synthesis of Polyaniline by Laccase Enzyme. Journal of Chemical Technology and Biotechnology. 96(4), 1107–1115. DOI: https://doi.org/10.1002/jctb.6626

[67] Khlupova, M., Vasil'eva, I., Shumakovich, G., et al., 2021. Enzymatic Polymerization of Dihydroquercetin (Taxifolin) in Betaine-Based Deep Eutectic Solvent and Product Characterization. Catalysts. 11(5), 639. DOI: https://doi.org/10.3390/catal11050639

[68] Putro, J.N., Soetaredjo, F.E., Lin, S.-Y., et al., 2016. Pretreatment and Conversion of Lignocellulose Biomass into Valuable Chemicals. RSC Advances. 6(52), 46834–46852. DOI: https://doi.org/10.1039/C6RA09851G

[69] Bajpai, P., 2016. Structure of Lignocellulosic Biomass. In Pretreatment of Lignocellulosic Biomass for Biofuel Production. Springer: Singapore. pp. 7–12. DOI: https://doi.org/10.1007/978-981-10-0687-6_2

[70] Mankar, A.R., Pandey, A., Modak, A., et al., 2021. Pretreatment of Lignocellulosic Biomass: A Review on Recent Advances. Bioresource Technology. 334, 125235. DOI: https://doi.org/10.1016/j.biortech.2021.125235

[71] Tong, J., Hu, W., Qin, Y., et al., 2023. Deep Eutectic Solvent Pretreatment for Green Preparation of Nanocellulose. Cellulose. 30, 4773–4792. DOI: https://doi.org/10.1007/s10570-023-05154-3

[72] Hong, S., Shen, X.-J., Pang, B., et al., 2020. In-Depth Interpretation of the Structural Changes of Lignin and Formation of Diketones during Acidic Deep Eutectic Solvent Pretreatment. Green Chemistry. 22, 1851–1858. DOI: https://doi.org/10.1039/D0GC00006J

[73] Luo, T., Wang, C., Ji, X., et al., 2021. Innovative Production of Lignin Nanoparticles Using Deep Eutectic Solvents for Multifunctional Nanocomposites. International Journal of Biological Macromolecules. 183, 781–789. DOI: https://doi.org/10.1016/j.ijbiomac.2021.05.005

[74] Shen, F., He, C., Wang, Y., et al., 2023. Fully Upgrade Lignocellulose to Three Nanomaterials by Combinational Pretreatment: Refining Straw Waste to Pesticide Nanocarrier. Chemical Engineering Journal. 467, 143376. DOI: https://doi.org/10.1016/j.cej.2023.143376

[75] Wang, Y., Liu, H., Ji, X., et al., 2023. Production of Nanocellulose Using Acidic Deep Eutectic Solvents Based on Choline Chloride and Carboxylic Acids: A Review. International Journal of Biological Macromolecules. 245, 125227. DOI: https://doi.org/10.1016/j.ijbiomac.2023.125227

[76] Zhang, F., Huang, J., Wu, Z., et al., 2025. Lignin-Derived Deep Eutectic Solvent for Biomass Fractionation Based on α,γ-Diol Lignin Stabilization Strategy. International Journal of Biological Macromolecules. 308, 142053. DOI: https://doi.org/10.1016/j.ijbiomac.2025.142053

[77] Willberg-Keyriläinen, P., Hiltunen, J., Ropponen, J., 2018. Production of Cellulose Carbamate Using Urea-Based Deep Eutectic Solvents. Cellulose. 25, 195–204. DOI: https://doi.org/10.1007/s10570-017-1465-9

[78] Liao, J., Wen, R., Zhao, X., et al., 2024. Quaternized Chitin as Biomaterial for Multiple Applications. Cellulose. 31, 4063–4083. DOI: https://doi.org/10.1007/s10570-024-05902-z

[79] Yuan, Y., Hong, S., Lian, H., et al., 2020. Comparison of Acidic Deep Eutectic Solvents in Production of Chitin Nanocrystals. Carbohydrate Polymers. 236, 116095. DOI: https://doi.org/10.1016/j.carbpol.2020.116095

[80] Li, Z., Liu, C., Hong, S., et al., 2022. Recent Advances in Extraction and Processing of Chitin Using Deep Eutectic Solvents. Chemical Engineering Journal. 446, 136953. DOI: https://doi.org/10.1016/j.cej.2022.136953

[81] Elieh-Ali-Komi, D., Hamblin, M.R., 2016. Chitin and Chitosan: Production and Application of Versatile Biomedical Nanomaterials. International Journal of Advanced Research. 4, 411–427.

[82] Zehra, A., Amin, T., Wani, S.M., et al., 2024. Chitosan-Based Films. In: Amin, T., Naik, H.R., Hussain, S.Z., et al. (Eds.). Polysaccharide Based Films for Food Packaging: Fundamentals, Properties and Applications. Springer: Singapore. pp. 121–144. DOI: https://doi.org/10.1007/978-981-99-4898-7_5

[83] Whistler, R.L., Daniel, J.R., 2000. Starch. In Kirk-Othmer Encyclopedia of Chemical Technology. Wiley: Hoboken, NJ, USA. DOI: https://doi.org/10.1002/0471238961.1920011823080919.a01

[84] Skowrońska, D., Wilpiszewska, K., 2022. Deep Eutectic Solvents for Starch Treatment. Polymers. 14(2), 220. DOI: https://doi.org/10.3390/polym14020220

[85] Zdanowicz, M., Wilpiszewska, K., Spychaj, T., 2018. Deep Eutectic Solvents for Polysaccharides Processing. A Review. Carbohydrate Polymers. 200, 361–380. DOI: https://doi.org/10.1016/j.carbpol.2018.07.078

[86] Zdanowicz, M., Staciwa, P., Jędrzejewski, R., et al., 2019. Sugar Alcohol-Based Deep Eutectic Solvents as Potato Starch Plasticizers. Polymers. 11(9), 1385. DOI: https://doi.org/10.3390/polym11091385

[87] Yan, T., Luo, X., He, X., et al., 2025. Waxy Maize Starch Treatment with Acidic Deep Eutectic Solvents: Effect of Molar Ratio and Carboxylic Acids' Structure. International Journal of Biological Macromolecules. 304, 140886. DOI: https://doi.org/10.1016/j.ijbiomac.2025.140886

[88] Zdanowicz, M., Sałasińska, K., 2023. Characterization of Thermoplastic Starch Plasticized with Ternary Urea-Polyols Deep Eutectic Solvent with Two Selected Fillers: Microcrystalline Cellulose and Montmorillonite. Polymers. 15(4), 972. DOI: https://doi.org/10.3390/polym15040972

[89] Zdanowicz, M., 2021. Deep Eutectic Solvents Based on Urea, Polyols and Sugars for Starch Treatment. International Journal of Biological Macromolecules. 176, 387–393. DOI: https://doi.org/10.1016/j.ijbiomac.2021.02.039

[90] Xiao, Q., Dai, M., Zhou, H., et al., 2022. Formation and Structure Evolution of Starch Nanoplatelets by Deep Eutectic Solvent of Choline Chloride/Oxalic Acid Dihydrate Treatment. Carbohydrate Polymers. 282, 119105. DOI: https://doi.org/10.1016/j.carbpol.2022.119105

[91] Yu, D., Xue, Z., Mu, T., 2022. Deep Eutectic Solvents as a Green Toolbox for Synthesis. Cell Reports Physical Science. 3(4), 100809. DOI: https://doi.org/10.1016/j.xcrp.2022.100809

[92] Kaur, H., 2026. Deep Eutectic Solvent (DES)-Based Gels: Structure, Properties, and Emerging Pharmaceutical Applications. ChemRxiv. DOI: https://doi.org/10.26434/chemrxiv-2026-mjlk8

[93] Jaumaux, P., Liu, Q., Zhou, D., et al., 2020. Deep-Eutectic-Solvent-Based Self-Healing Polymer Electrolyte for Safe and Long-Life Lithium-Metal Batteries. Angewandte Chemie International Edition. 59(23), 9134–9142. DOI: https://doi.org/10.1002/anie.202001793

[94] Bednarz, S., Fluder, M., Galica, M., et al., 2014. Synthesis of Hydrogels by Polymerization of Itaconic Acid–Choline Chloride Deep Eutectic Solvent. Journal of Applied Polymer Science. 131(16). DOI: https://doi.org/10.1002/app.40608

[95] Wang, X., Chen, G., Cai, L., et al., 2021. Weavable Transparent Conductive Fibers with Harsh Environment Tolerance. ACS Applied Materials & Interfaces. 13(7), 8952–8959. DOI: https://doi.org/10.1021/acsami.0c21912

[96] Wu, L., Zhou, J., Bu, X., et al., 2022. Highly Stretchable, Self-Recoverable, and Conductive Double-Network Gels Containing Deep Eutectic Solvent for a Flexible Supercapacitor and Strain Sensor. Journal of Electronic Materials. 51(9), 5074–5086. DOI: https://doi.org/10.1007/s11664-022-09743-z

[97] Prasad, K., Mondal, D., Sharma, M., et al., 2018. Stimuli Responsive Ion Gels Based on Polysaccharides and Other Polymers Prepared Using Ionic Liquids and Deep Eutectic Solvents. Carbohydrate Polymers. 180, 328–336. DOI: https://doi.org/10.1016/j.carbpol.2017.10.020

[98] Fan, K., Wei, W., Zhang, Z., et al., 2022. Highly Stretchable, Self-Healing, and Adhesive Polymeric Eutectogel Enabled by Hydrogen-Bond Networks for Wearable Strain Sensor. Chemical Engineering Journal. 449, 137878. DOI: https://doi.org/10.1016/j.cej.2022.137878

[99] Mercadal, P.A., Romero, M.R., Montesinos, M.d.M., et al., 2023. Natural, Biocompatible, and 3D-Printable Gelatin Eutectogels Reinforced with Tannic Acid-Coated Cellulose Nanocrystals for Sensitive Strain Sensors. ACS Applied Electronic Materials. 5(4), 2184–2196. DOI: https://doi.org/10.1021/acsaelm.3c00075

[100] Biswas, R., Metya, A.K., Abebe, K.M., et al., 2023. Carbon Dioxide Solubility in Choline Chloride-Based Deep Eutectic Solvents under Diverse Conditions. Journal of Molecular Modeling. 29(8), 236. DOI: https://doi.org/10.1007/s00894-023-05643-z

[101] Yadav, T.C., Srivastava, A.K., Mishra, P., et al., 2019. Electrospinning: An Efficient Biopolymer-Based Micro- and Nanofibers Fabrication Technique. In: Rathinam, N.K., Sani, R.K. (Eds.). Next Generation Biomanufacturing Technologies. American Chemical Society: Washington, DC, USA. pp. 209–241. DOI: https://doi.org/10.1021/bk-2019-1329.ch010

[102] Sousa, A.M.M., Souza, H.K.S., Uknalis, J., et al., 2015. Improving Agar Electrospinnability with Choline-Based Deep Eutectic Solvents. International Journal of Biological Macromolecules. 80, 139–148. DOI: https://doi.org/10.1016/j.ijbiomac.2015.06.034

[103] Mano, F., Aroso, I.M., Barreiros, S., et al., 2015. Production of Poly(vinyl Alcohol) (PVA) Fibers with Encapsulated Natural Deep Eutectic Solvent (NADES) Using Electrospinning. ACS Sustainable Chemistry & Engineering. 3(10), 2504–2509. DOI: https://doi.org/10.1021/acssuschemeng.5b00613

[104] Mouro, C., Martins, R., Gomes, A.P., et al., 2023. Upcycling Wool Waste into Keratin Gel-Based Nanofibers Using Deep Eutectic Solvents. Gels. 9(8), 661. DOI: https://doi.org/10.3390/gels9080661

[105] Zhang, Q., Lin, Z., Zhang, W., et al., 2020. Fabrication of Green Poly(vinyl Alcohol) Nanofibers Using Natural Deep Eutectic Solvent for Fast-Dissolving Drug Delivery. RSC Advances. 11, 1012–1021. DOI: https://doi.org/10.1039/D0RA08755F

[106] Marincaș, L., Farkas, N.-I., Barbu-Tudoran, L., et al., 2023. Deep Eutectic Solvent PCL-Based Nanofibers as Drug Delivery System. Materials Chemistry and Physics. 304, 127862. DOI: https://doi.org/10.1016/j.matchemphys.2023.127862

[107] Lai, C.-W., Yu, S.-S., 2020. 3D Printable Strain Sensors from Deep Eutectic Solvents and Cellulose Nanocrystals. ACS Applied Materials & Interfaces. 12(30), 34235–34244. DOI: https://doi.org/10.1021/acsami.0c11152

[108] Sheikhi, M., Rafiemanzelat, F., Ghodsi, S., et al., 2022. 3D Printing of Jammed Self-Supporting Microgels with Alternative Mechanism for Shape Fidelity, Crosslinking and Conductivity. Additive Manufacturing. 58, 102997. DOI: https://doi.org/10.1016/j.addma.2022.102997

[109] Wang, S., Zhang, L., Ma, R., et al., 2023. A Novel One-Pot Strategy to Construct 3D-Printable Cellulose Nanofiber/Poly (Deep Eutectic Solvent) Conductive Elastomers. Chemical Engineering Journal. 454, 140022. DOI: https://doi.org/10.1016/j.cej.2022.140022

[110] Su, J., Li, S., Chen, Y., et al., 2021. 3D Photoprintable Antistatic Materials with Polymerizable Deep Eutectic Solvents. Industrial & Engineering Chemistry Research. 60, 17797–17803. DOI: https://doi.org/10.1021/acs.iecr.1c03317

[111] Cai, L., Chen, G., Tian, J., et al., 2021. Three-Dimensional Printed Ultrahighly Sensitive Bioinspired Ionic Skin Based on Submicrometer-Scale Structures by Polymerization Shrinkage. Chemistry of Materials. 33, 2072–2079. DOI: https://doi.org/10.1021/acs.chemmater.0c04581

[112] Zhu, G., Zhang, J., Huang, J., et al., 2022. Self-Healing, Antibacterial, and 3D-Printable Polymerizable Deep Eutectic Solvents Derived from Tannic Acid. ACS Sustainable Chemistry & Engineering. 10(24), 7954–7964. DOI: https://doi.org/10.1021/acssuschemeng.2c01328

[113] Li, Y., Kankala, R.K., Wu, L., et al., 2023. 3D-Printed Photocurable Resin with Synergistic Hydrogen Bonding Based on Deep Eutectic Solvent. ACS Applied Polymer Materials. 5(1), 991–1001. DOI: https://doi.org/10.1021/acsapm.2c01916

[114] Ramesh, S., Shanti, R., Morris, E., 2013. Characterization of Conducting Cellulose Acetate Based Polymer Electrolytes Doped with 'Green' Ionic Mixture. Carbohydrate Polymers. 91(1), 14–21. DOI: https://doi.org/10.1016/j.carbpol.2012.07.061

[115] Pulyalina, A., Rostovtseva, V., Faykov, I., et al., 2021. Development of Novel Polyamide-Imide/DES Composites and Their Application for Pervaporation and Gas Separation. Molecules. 26(4), 990. DOI: https://doi.org/10.3390/molecules26040990

[116] Russo, F., Tiecco, M., Galiano, F., et al., 2022. Launching Deep Eutectic Solvents (DESs) and Natural Deep Eutectic Solvents (NADESs), in Combination with Different Harmless Co-Solvents, for the Preparation of More Sustainable Membranes. Journal of Membrane Science. 649, 120387. DOI: https://doi.org/10.1016/j.memsci.2022.120387

[117] Khajavian, M., Vatanpour, V., Castro-Muñoz, R., et al., 2022. Chitin and Derivative Chitosan-Based Structures—Preparation Strategies Aided by Deep Eutectic Solvents: A Review. Carbohydrate Polymers. 275, 118702. DOI: https://doi.org/10.1016/j.carbpol.2021.118702

[118] Shafie, M.H., Yusof, R., Samsudin, D., et al., 2020. Averrhoa bilimbi Pectin-Based Edible Films: Effects of the Linearity and Branching of the Pectin on the Physicochemical, Mechanical, and Barrier Properties of the Films. International Journal of Biological Macromolecules. 163, 1276–1282. DOI: https://doi.org/10.1016/j.ijbiomac.2020.07.109

[119] Sousa, A.S.B.D., Lima, R.P., Silva, M.C.A.D., et al., 2022. Natural Deep Eutectic Solvent of Choline Chloride with Oxalic or Ascorbic Acids as Efficient Starch-Based Film Plasticizers. Polymer. 259, 125314. DOI: https://doi.org/10.1016/j.polymer.2022.125314

[120] Zeraatkar Moghaddam, A., Tabani, H., Bameri, A., et al., 2024. Agarose-Based Gel Electromembrane Extraction Using Silica Nanoparticles Coated with Polymeric Deep Eutectic Solvent as a Membrane Additive. Journal of Molecular Liquids. 401, 124615. DOI: https://doi.org/10.1016/j.molliq.2024.124615

[121] Guo, Y., Tian, D., Shen, F., et al., 2019. Transparent Cellulose/Technical Lignin Composite Films for Advanced Packaging. Polymers. 11(9), 1455. DOI: https://doi.org/10.3390/polym11091455

[122] Xia, Q., Chen, C., Yao, Y., et al., 2021. A Strong, Biodegradable and Recyclable Lignocellulosic Bioplastic. Nature Sustainability. 4(7), 627–635. DOI: https://doi.org/10.1038/s41893-021-00702-w

[123] Yu, J., Xu, S., Goksen, G., et al., 2023. Chitosan Films Plasticized with Choline-Based Deep Eutectic Solvents: UV Shielding, Antioxidant, and Antibacterial Properties. Food Hydrocolloids. 135, 108196. DOI: https://doi.org/10.1016/j.foodhyd.2022.108196

[124] Moon, G.Y., Youn, H.S., Kim, G.H., et al., 2025. Effect and Characterization Comparison of Various Deep Eutectic Solvent Types in Pretreatment of Lignocellulosic Biomass and Bioplastic Production. Industrial Crops and Products. 225, 120452. DOI: https://doi.org/10.1016/j.indcrop.2024.120452

[125] Wan Chik, M., Hadi, N., Yusof, R., 2025. Effect of Choline Chloride/Citric Acid Ratios on Physical and Mechanical Properties of Citrus Maxima Rind Pectin-Based Bioplastic. Journal of Advanced Research in Fluid Mechanics and Thermal Sciences. 127(1), 223–236. DOI: https://doi.org/10.37934/arfmts.127.1.223236

[126] Mane, R.S., Jadhav, V., Al-Enizi, A.M., 2023. Solution Methods for Metal Oxide Nanostructures. Elsevier: Amsterdam, The Netherlands. pp. 197–220.

[127] Simka, W., Puszczyk, D., Nawrat, G., 2009. Electrodeposition of Metals from Non-Aqueous Solutions. Electrochimica Acta. 54(23), 5307–5319. DOI: https://doi.org/10.1016/j.electacta.2009.04.028

[128] Ferreira, E.S.C., Pereira, C.M., Silva, A.F., 2013. Electrochemical Studies of Metallic Chromium Electrodeposition from a Cr(III) Bath. Journal of Electroanalytical Chemistry. 707, 52–58. DOI: https://doi.org/10.1016/j.jelechem.2013.08.005

[129] Smith, E.L., Abbott, A.P., Ryder, K.S., 2014. Deep Eutectic Solvents (DESs) and Their Applications. Chemical Reviews. 114(21), 11060–11082. DOI: https://doi.org/10.1021/cr300162p

[130] Popescu, A.-M., Cojocaru, A., Donath, C., et al., 2013. Electrochemical Study and Electrodeposition of Copper(I) in Ionic Liquid-Reline. Chemistry Research in Chinese Universities. 29(5), 991–997. DOI: https://doi.org/10.1007/s40242-013-3013-y

[131] Pollet, B.G., Hihn, J.-Y., Mason, T.J., 2008. Sono-Electrodeposition (20 and 850 kHz) of Copper in Aqueous and Deep Eutectic Solvents. Electrochimica Acta. 53(12), 4248–4256. DOI: https://doi.org/10.1016/j.electacta.2007.12.059

[132] Abbott, A.P., Capper, G., McKenzie, K.J., et al., 2006. Voltammetric and Impedance Studies of the Electropolishing of Type 316 Stainless Steel in a Choline Chloride Based Ionic Liquid. Electrochimica Acta. 51(21), 4420–4425. DOI: https://doi.org/10.1016/j.electacta.2005.12.030

[133] Wang, S., Zhang, Z., Lu, Z., et al., 2020. A Novel Method for Screening Deep Eutectic Solvent to Recycle the Cathode of Li-Ion Batteries. Green Chemistry. 22(14), 4473–4482. DOI: https://doi.org/10.1039/D0GC00701C

[134] Abbott, A.P., Capper, G., Davies, D.L., et al., 2006. Solubility of Metal Oxides in Deep Eutectic Solvents Based on Choline Chloride. Journal of Chemical & Engineering Data. 51(4), 1280–1282. DOI: https://doi.org/10.1021/je060038c

[135] Tran, M.K., Rodrigues, M.-T.F., Kato, K., et al., 2019. Deep Eutectic Solvents for Cathode Recycling of Li-Ion Batteries. Nature Energy. 4(4), 339–345. DOI: https://doi.org/10.1038/s41560-019-0368-4

[136] Roldán-Ruiz, M.J., Ferrer, M.L., Gutiérrez, M.C., et al., 2020. Highly Efficient p-Toluenesulfonic Acid-Based Deep-Eutectic Solvents for Cathode Recycling of Li-Ion Batteries. ACS Sustainable Chemistry & Engineering. 8(14), 5437–5445. DOI: https://doi.org/10.1021/acssuschemeng.0c00892

[137] Ammar, M., Ashraf, S., Gonzalez-Casamachin, D.A., et al., 2024. Recent Progress of Urea-Based Deep Eutectic Solvents as Electrolytes in Battery Technology: A Critical Review. Batteries. 10(2), 45. DOI: https://doi.org/10.3390/batteries10020045

[138] Azmi, S., Koudahi, M.F., Frackowiak, E., 2022. Reline Deep Eutectic Solvent as a Green Electrolyte for Electrochemical Energy Storage Applications. Energy & Environmental Science. 15(3), 1156–1171. DOI: https://doi.org/10.1039/D1EE02920G

[139] Zhang, C., Zheng, H., Lin, L., et al., 2024. Deep Eutectic Solvent-Based Solid Polymer Electrolytes for High-Voltage and High-Safety Lithium Metal Batteries. Advanced Energy Materials. 14(35), 2401324. DOI: https://doi.org/10.1002/aenm.202401324

[140] Ruiz-Olles, J., Slavik, P., Whitelaw, N.K., et al., 2019. Self-Assembled Gels Formed in Deep Eutectic Solvents: Supramolecular Eutectogels with High Ionic Conductivity. Angewandte Chemie International Edition. 58(13), 4173–4178. DOI: https://doi.org/10.1002/anie.201810600

[141] Li, J., Tu, J., Jiao, H., et al., 2017. Ternary AlCl₃-Urea-[EMIm]Cl Ionic Liquid Electrolyte for Rechargeable Aluminum-Ion Batteries. Journal of the Electrochemical Society. 164(13), A3093–A3100. DOI: https://doi.org/10.1149/2.0811713jes

[142] Ng, K.L., Malik, M., Buch, E., et al., 2019. A Low-Cost Rechargeable Aluminum/Natural Graphite Battery Utilizing Urea-Based Ionic Liquid Analog. Electrochimica Acta. 327, 135031. DOI: https://doi.org/10.1016/j.electacta.2019.135031

[143] Li, C.-L., Huang, G., Yu, Y., et al., 2022. A Low-Volatile and Durable Deep Eutectic Electrolyte for High-Performance Lithium–Oxygen Battery. Journal of the American Chemical Society. 144(13), 5827–5833. DOI: https://doi.org/10.1021/jacs.1c11711

[144] Zhang, T., Yu, J., Lin, T., et al., 2025. Fluorinated Deep Eutectic Gel Electrolytes for Sustainable Lithium Metal Batteries. Journal of the American Chemical Society. 147(36), 32861–32872. DOI: https://doi.org/10.1021/jacs.5c08642

[145] Zhang, X., Tang, Q., Luo, H., et al., 2025. Hydrogen Bond Reconstruction Maneuver in Eutectic Electrolyte Enables Ultralong-Lifespan Zinc-Ion Batteries. Journal of the American Chemical Society. 147(43), 39440–39451. DOI: https://doi.org/10.1021/jacs.5c12021

[146] Stettler, A.M., Blanchard, S.S., Baker, G.A., et al., 2026. The Direct Piezoelectric Effect in Deep Eutectic Solvents. Journal of the American Chemical Society. 148(6), 5900–5904. DOI: https://doi.org/10.1021/jacs.5c21126

[147] Yadav, N., Ansari, M.D., Yadav, V.B., et al., 2021. Metal-Free Visible-Light-Mediated Organophotoredox Catalysis: Synthesis of 3-Functionalized Indole via C–C, C–N Bond Formation. Molecular Diversity. 25(2), 1103–1109. DOI: https://doi.org/10.1007/s11030-020-10044-y

[148] Tiwari, S.K., Nazeef, M., Verma, A., et al., 2022. BF₃-Etherate Promoted Facile Access to Vinyloxyimidazopyridines: A Metal-Free Sustainable Approach. Molecular Diversity. 26, 1259–1266. DOI: https://doi.org/10.1007/s11030-021-10228-0

[149] Shuheil, M.A., Zaki, M.E.A., Priya, G.P., et al., 2026. Cu(II)–Functionalized Magnetic Fe₃O₄@SiO₂–TCCP Catalyst for the Synthesis of Imidazo[1,2-a]pyridines in Deep Eutectic Solvents. Journal of Inorganic and Organometallic Polymers and Materials. DOI: https://doi.org/10.1007/s10904-025-04157-w

[150] Chegeni, E., Habibi, D., Monem, A., 2026. The Arginine/Gallic Acid-Based Deep Eutectic Solvent as a Capable Catalyst for the Green Synthesis of Pyrano[2,3-d]pyrimidines. Scientific Reports. 16, 4627. DOI: https://doi.org/10.1038/s41598-025-34760-3

[151] Tran, T.-A.N., Nguyen, L.D., Nguyen, K.N., et al., 2026. A Brønsted-Based Deep Eutectic Solvent as a Green Catalyst for the Sustainable One-Pot Synthesis of 1,2,4,5-Tetrasubstituted Imidazole Derivatives: In Vitro Cytotoxicity and In Silico Binding Studies on HepG2 Cells. RSC Advances. 16(17), 15249–15265. DOI: https://doi.org/10.1039/D6RA00422A

[152] Xiong, J., Liu, J., Lu, J., et al., 2026. Tunable Deep Eutectic Solvents for Selective Production of 5-Methylfurfural from Enteromorpha prolifera Derived Rhamnose: A Mechanistic Insight. Journal of Environmental Chemical Engineering. 14(2), 121542. DOI: https://doi.org/10.1016/j.jece.2026.121542

Downloads

How to Cite

Saurabh Kumar Tiwari, Pratibha Yadav, Mrigank Mauli Dwivedi, & Pandey, K. (2026). Natural Deep Eutectic Solvents: A New Environment Friendly Solvent. New Environmentally-Friendly Materials, 5(1), 1–26. https://doi.org/10.55121/nefm.v5i1.1182