1. Pathan S. and Bose S., Arsenic Removal Using Green Renew-able Feedstock-Based Hydrogels: Current and Future Perspec-tives, ACS. Omega, 3, 5910-5917, 2018.
2. Jiang L. and Liu P., Design of Magnetic Attapulgite/Fly Ash/Poly(acrylic acid) Ternary Nanocomposite Hydrogels and
Performance Evaluation as Selective Adsorbent for Pb2+ Ion, ACS Sustain. Chem. Eng., 2, 1785-1794, 2014.
3. Yahia L., History and Applications of Hydrogels, J. Biomed.Sci., 4, 13, 2015. 4. Liu R., Liang S., Tang X.-Z., Yan D., Li X., and Yu Z.-Z., Tough and Highly Stretchable Graphene Oxide/Polyacryl-amide Nanocomposite Hydrogels, J. Mater. Chem., 22, 14160-14167, 2012.
5. Chowdhury N., Solaiman, Roy C.K., Firoz S.H., Foyez T., and Imran A.B., Role of Ionic Moieties in Hydrogel Networks to
Remove Heavy Metal Ions from Water, ACS Omega, 6, 836-844, 2021.
6. Perumal S., Atchudan R., Edison T.N.J.I., Babu R.S., Karp-agavinayagam P., and Vedhi C., A Short Review on Recent
Advances of Hydrogel-Based Adsorbents for Heavy Metal Ions, Metals, 11, 864, 2021. doi: 10.3390/met11060864
7. Badsha M.A.H., Khan M., Wu B., Kumar A., and Lo I.M.C., Role of Surface Functional Groups of Hydrogels in Metal Ad-
sorption: From Performance to Mechanism, J. Hazard. Ma-ter., 408, 124463, 2021.
8. Godiya C.B., Martins Ruotolo L.A., and Cai W., Functional Biobased Hydrogels for the Removal of Aqueous Hazardous
Pollutants: Current Status, Challenges, and Future Perspec-tives, J. Mater. Chem., 8, 21585-21612, 2020.
9. Wahlstrom N., Steinhagen S., Toth G., Pavia H., and Edlund U., Ulvan Dialdehyde-Gelatin Hydrogels for Removal of
Heavy Metals and Methylene Blue from Aqueous Solution, Carbohydr. Polym., 249, 116841, 2020.
10. Wang W., Kang Y., and Wang A., One-Step Fabrication in Aqueous Solution of a Granular Alginate-Based Hydrogel for Fast and Efficient Removal of Heavy Metal Ions, J. Polym. Res., 20, 101, 2013.
11. Bandara P.C., Perez J.V.D., Nadres E.T., Nannapaneni R.G., Krakowiak K.J., and Rodrigues D.F., Graphene Oxide Nano-
composite Hydrogel Beads for Removal of Selenium in Con-taminated Water, ACS Appl. Polym. Mater., 1, 2668-2679,
2019.
12. Duc T.H., Vu T.K., Dang C.T., Nguyen V.H., La D.D., Kim G.M. et al., Synthesis and Application of Hydrogel Calcium
Alginate Microparticles as a Biomaterial to Remove Heavy Metals from Aqueous Media, Environ. Technol. Innov., 22,
101400, 2021.
13. Yang F., Yu P., Yang Z., Zhang X., and Ma J., Double-Network Hydrogel Adsorbents for Environmental Applications, Chem. Eng. J., 426, 131900, 2021.
14. Wu X., Shao G., Shen X., Cui S., and Wang L., Novel Al2O3–SiO2 Composite Aerogels with High Specific Surface Area at Elevated Temperatures with Different Alumina/Silica Molar Ratios Prepared by a Non-Alkoxide Sol–Gel Method, RSC
Adv., 6, 5611-5620, 2016.
15. Shaheed N., Javanshir S., Esmkhani M., Dekamin M.G., and Naimi-Jamal M.R., Synthesis of Nanocellulose Aerogels and Cu-BTC/Nanocellulose Aerogel Composites for Adsorption of Organic Dyes and Heavy Metal Ions, Sci. Rep., 11, 18553,
2021.
16. Tian C., She J., Wu Y., Luo S., Wu Q., and Qing Y., Reusable and Cross-Linked Cellulose Nanofibrils Aerogel for the
Removal of Heavy Metal Ions, Polym. Compos., 39, 4442-4451, 2017.
17. Liu X.G., Mao Q.S., Jiang Y., Li Y., Sun J.L., and Huang F.X., Preparation of Al2O3-SiO2 Composite Aerogels and their Cu2+ Absorption Properties, Int. J. Min. Met. Mater., 28, 317-324, 2021.
18. Huang Y. and Wang Z., Preparation of Composite Aerogels Based on Sodium Alginate, and Its Application in Removal of Pb(2+) and Cu(2+) from Water, Int. J. Biol. Macromol., 107, 741-747, 2018.
19. Pekala R.W., Organic Aerogels from the Polycondensation of Resorcinol with Formaldehyde. J. Mater. Sci., 24, 3221-3227, 1989.
20. Ye J., Wu Q., Peng C., Xu H., Zhang J., Xie T. et al., Surface Migration of Pb(II) From Water and Soil Using an Aerogel/
Graphite Felt Primary Cell System, Chemosphere, 294, 133666, 2022.
21. Wang M., Wang Z., Zhou X., and Li S., Efficient Removal of Heavy Metal Ions in Wastewater by Using a Novel Alginate-
EDTA Hybrid Aerogel, Appl. Sci., 9, 547, 2019.
22. Bajpai S.K. and Sharma S., Investigation of Swelling/Degra-dation Behaviour of Alginate Beads Crosslinked with Ca2+ and Ba2+ Ions, React. Funct. Polym., 59, 129-140, 2004.
23. Wang J. and Li Z., Enhanced Selective Removal of Cu(II) from Aqueous Solution by Novel Polyethylenimine- Functionalized Ion Imprinted Hydrogel: Behaviors and Mech-anisms, J. Hazard. Mater., 300, 18-28, 2015.
24. Nair S.S. and Yan N., Bark Derived Submicron-Sized and Nano-Sized Cellulose Fibers: From Industrial Waste to High
Performance Materials, Carbohydr. Polym., 134, 258-266, 2015.
25. Tian C., Yi J., Wu Y., Wu Q., Qing Y., and Wang L., Prepa-ration of Highly Charged Cellulose Nanofibrils Using High-
Pressure Homogenization Coupled with Strong Acid Hydrolysis Pretreatments, Carbohydr. Polym., 136, 485-492, 2016.
26. Mi X., Huang G., Xie W., Wang W., Liu Y., and Gao J., Prepa-ration of Graphene Oxide Aerogel and Its Adsorption for Cu2+ Ions, Carbon, 50, 4856-4864, 2012.
27. Li Z. and Ngai T., Microgel Particles at the Fluid-Fluid Inter-faces, Nanoscale, 5, 1399-1410, 2013.
28. He Z. et al., Degradable CO2-Responsive Microgels with Wrinkled Porous Structure for Enhanced, Selective and
Recyclable Removal of Anionic Dyes, Cr(VI) and As(V), Eur. Polym. J., 149, 110374, 2021.29. Jiang L. and Liu P., Novel Magnetic Fly Ash/Poly(acrylic acid) Composite Microgel for Selective Adsorption of Pb(II) Ion: Synthesis and Evaluation, Ind. Eng. Chem. Res., 53, 2924-2931, 2014.
30. Liu P., Jiang L., Zhu L., and Wang A., Novel Approach for Attapulgite/Poly(acrylic acid) (ATP/PAA) Nanocomposite
Microgels as Selective Adsorbent for Pb(II) Ion, React. Funct. Polym., 74, 72-80, 2014.
31. Jaworski Z., Spychaj T., Story A., and Story G., Carbomer Microgels as Model Yield-Stress Fluids, Rev. Chem. Eng., 38,
2021.
32. El-Bahy S.M., Fadel D.A., El-Bahy Z.M., and Metwally A.M.,Rapid and Highly Efficient Cesium Removal by Newly Syn-
thesized Carbomer Encapsulated Potassium Copper Hexacya-noferrate Composite, J. Environ. Chem. Eng., 6, 1875-1885,
2018.
33 Kabanov A.V. and Vinogradov S.V., Nanogels as Pharmaceu-tical Carriers: Finite Networks of Infinite Capabilities, Angew.Chem. Int. Ed., 48, 5418-5429, 2009.
34. Shailesh D.G., Pooja S.M., Yogesh M.P., Ashwini D.C., andMilind J.U., Overview of Nanogel and Its Applications, GSC
Biol. Pharm. Sci., 16, 040-061, 2021.