Skip to main content
Article
Licensed
Unlicensed Requires Authentication

Gamma radiation-assisted synthesis and characterization of CdS-doped bio-hydrogel for ethyl violet dye removal from aqueous solution: isotherm, kinetic, and thermodynamic studies

  • , ORCID logo , and ORCID logo EMAIL logo
Published/Copyright: February 5, 2026
Radiochimica Acta
From the journal Radiochimica Acta

Abstract

This paper investigates the intricate synthesis methods of radiation-induced hydrogels, focusing on their structural characteristics and functional benefits. Specifically, Pectin/PVP/CdS nanocomposite hydrogels were prepared by gamma-radiation copolymerization of Pectin and Poly (vinyl pyrrolidone) (PVP) in the presence of cadmium sulphide nanoparticles (CdS NPs). The study systematically examined how the irradiation dose, the incorporation of CdS NPs, and varying Pectin/PVP ratios affect the resulting gel content and swelling properties. Comprehensive structural characterization was performed using FTIR, UV/vis, XRD, SEM, EDX, and TEM. Significantly, the prepared nanocomposite was then employed as an efficient adsorbent for removing ethyl violet (EV) dye from aqueous solutions. Results indicated that the Pectin/PVP/CdS nanocomposite exhibited a substantially higher adsorption capacity than the Pectin/PVP control, achieving up to 90 % removal efficiency under optimal conditions. Adsorption kinetics confirmed a best fit with the pseudo-second-order model, indicating that a chemical interaction is the rate-limiting step, while the process itself is exothermic and follows the Freundlich isotherm model.

Keywords: hydrogel; CdS; pectin and gamma radiation
Corresponding author: Rehab Sokary, Radiation Chemistry Department, National Center for Radiation Research and Technology, Egyptian Atomic Energy Authority, Cairo, Egypt, E-mail:

  1. Research ethics: Not applicable.

  2. Informed consent: Not applicable.

  3. Author contributions: All authors have accepted responsibility for the entire content of this manuscript and approved its submission.

  4. Use of Large Language Models, AI and Machine Learning Tools: None declared.

  5. Conflict of interest: All other authors state no conflict of interest.

  6. Research funding: None declared.

  7. Data availability: Not applicable.

References

1. Ravikumar, S.; Mani, D.; Chicardi, E.; Sepúlveda, R.; Balu, K.; Pandiyan, V.; Ahn, Y. H. Development of Highly Efficient cost-effective cds/ag Nanocomposite for Removal of Azo Dyes Under Uv and Solar Light. Ceram. Int. 2023, 49 (6), 9551–9559; https://doi.org/10.1016/j.ceramint.2022.11.123.Search in Google Scholar

2. Reffas, A.; Bouguettoucha, A.; Chebli, D.; Amrane, A. Adsorption of Ethyl Violet Dye in Aqueous Solution by Forest Wastes, Wild Carob. Desalina. Water Treat. 2016, 57 (21), 9859–9870; https://doi.org/10.1080/19443994.2015.1031707.Search in Google Scholar

3. Ahmed, R.; Islam, S.; Hossain, M. A. Characterization of Ethyl Violet Adsorption on Used Black Tea Leaves from Aquatic Environment: Kinetic, Isotherm and Thermodynamic Studies. American J. Physi. Chem. 2021, 10 (2), 38–47; https://doi.org/10.11648/j.ajpc.20211002.14.Search in Google Scholar

4. Poornachandhra, C.; Jayabalakrishnan, R. M.; Prasanthrajan, M.; Balasubramanian, G.; Lakshmanan, A.; Selvakumar, S.; John, J. E. Cellulose-Based Hydrogel for Adsorptive Removal of Cationic Dyes from Aqueous Solution: Isotherms and Kinetics. RSC adv. 2023, 13 (7), 4757–4774; https://doi.org/10.1039/d2ra08283g.Search in Google Scholar PubMed PubMed Central

5. El-Din, H. M. N.; Ibraheim, D. M.; Rabie, A. G. M. Characterization and Drug Delivery Characters of Nanocomposite Hydrogels Based on gamma-radiation Copolymerization of Poly (Vinyl Pyrrolidone) (pvp)/sodium Alginate (Ag)/silver Nps. Int. J. Biol. Macromol. 2023, 234–123674.10.1016/j.ijbiomac.2023.123674Search in Google Scholar PubMed

6. Chen, J.; Jiang, X.; Yin, D.; Zhang, W. Preparation of a Hydrogel-based Adsorbent for Metal Ions Through High Internal Phase Emulsion Polymerization. ACS omega 2020, 5 (32), 19920–19927; https://doi.org/10.1021/acsomega.9b03405.Search in Google Scholar PubMed PubMed Central

7. Mohamed, A. A.; Mahmoud, G. A.; El-Din, M. E.; Saad, E. Synthesis and Properties of (Gum acacia/polyacryamide/sio2) Magnetic Hydrogel Nanocomposite Prepared by Gamma Irradiation. Poly. Plastics Technolo. Mater. 2020, 59 (4), 357–370; https://doi.org/10.1080/25740881.2019.1647240.Search in Google Scholar

8. Rattanawongwiboon, T.; Hemvichian, K.; Lertsarawut, P.; Suwanmala, P. Chitosan-Poly (Ethylene Glycol) Diacrylate Beads Prepared by radiation-induced Crosslinking and their Promising Applications Derived from Encapsulation of Essential Oils. Radiat. Phys. Chem. 2020, 170–108656.10.1016/j.radphyschem.2019.108656Search in Google Scholar

9. Babaladimath, G.; Badalamoole, V. Pectin-Graft-Poly (2-acrylamido-2-methyl-1-propane Sulfonic Acid) Silver Nanocomposite Hydrogel Beads: Evaluation as Matrix Material for Sustained Release Formulations of Ketoprofen and Antibacterial Assay. J. Polym. Res. 2018, 25 (9), 202; https://doi.org/10.1007/s10965-018-1592-5.Search in Google Scholar

10. Zhang, P.; Li, W.; Zhai, X.; Liu, C.; Dai, L.; Liu, W. A Facile and Versatile Approach to Biocompatible “Fluorescent Polymers” from Polymerizable Carbon Nanodots. Chemi. Communi. 2012, 48 (84), 10431–10433; https://doi.org/10.1039/c2cc35966a.Search in Google Scholar PubMed

11. Qian, J.; Chen, J.; Ruan, S.; Shen, S.; He, Q.; Jiang, X.; Zhu, J.; Gao, H. Preparation and Biological Evaluation of Photoluminescent Carbonaceous Nanospheres. J. colloid inter. sci 2014, 429, 77–82; https://doi.org/10.1016/j.jcis.2014.05.016.Search in Google Scholar PubMed

12. Tan, X.; Liu, S.; Shen, Y.; He, Y.; Yang, J. Quantum Dots (Qds) Based Fluorescence Probe for the Sensitive Determination of Kaempferol. Spectrochim. Acta Part A: Molecu. Biomolecu. Spectrosco. 2014, 133, 66–72; https://doi.org/10.1016/j.saa.2014.05.032.Search in Google Scholar PubMed

13. De, B.; Voit, B.; Karak, N. Transparent Luminescent Hyperbranched epoxy/carbon Oxide Dot Nanocomposites with Outstanding Toughness and Ductility. ACS Appl. Mater. Interfaces 2013, 5 (20), 10027–10034; https://doi.org/10.1021/am402415g.Search in Google Scholar PubMed

14. Sahiner, N.; Sel, K.; Meral, K.; Onganer, Y.; Butun, S.; Ozay, O.; Silan, C. Hydrogel Templated Cds Quantum Dots Synthesis and their Characterization. Colloids and Surfaces A: Physicochem. Engin. Aspects 2011, 389 (1–3), 6–11; https://doi.org/10.1016/j.colsurfa.2011.09.006.Search in Google Scholar

15. Konwar, A.; Gogoi, N.; Majumdar, G.; Chowdhury, D. Green chitosan–carbon Dots Nanocomposite Hydrogel Film with Superior Properties. Carbohydr. polym 2015, 115, 238–245; https://doi.org/10.1016/j.carbpol.2014.08.021.Search in Google Scholar PubMed

16. Chauhan, G. S.; Kumari, A.; Sharma, R. Pectin and Acrylamide Based Hydrogels for Environment Management Technologies: Synthesis, Characterization, and Metal Ions Sorption. J. appl. polym. sci 2007, 106 (4), 2158–2168; https://doi.org/10.1002/app.26729.Search in Google Scholar

17. Song, M.; Wang, J.; He, J.; Kan, D.; Chen, K.; Lu, J. Synthesis of Hydrogels and their Progress in Environmental Remediation and Antimicrobial Application. Gels 2022, 9 (1), 16; https://doi.org/10.3390/gels9010016.Search in Google Scholar PubMed PubMed Central

18. Demir, G. , Ö.; Yavaş, A. Investigation of the Effects of Applying Gamma Irradiation as a Pre-treatment to Cotton Printed Fabric. Fiber. Poly. 2025, 1–16.Search in Google Scholar

19. Ghasempour, A.; Dehghan, H.; Ataee, M.; Chen, B.; Zhao, Z.; Sedighi, M.; Guo, X.; Shahbazi, M. A. Cadmium Sulfide Nanoparticles: Preparation, Characterization, and Biomedical Applications. Molecules 2023, 28 (9), 3857; https://doi.org/10.3390/molecules28093857.Search in Google Scholar PubMed PubMed Central

20. Fares, M. M.; Assaf, S. M.; Abul‐Haija, Y. M. Pectin Grafted Poly (N‐Vinylpyrrolidone): Optimization and in Vitro Controllable Theophylline Drug Release. J. Appl. Polym. Sci. 2010, 117 (4), 1945–1954; https://doi.org/10.1002/app.32172.Search in Google Scholar

21. Chauhan, K.; Kumar, R.; Kumar, M.; Sharma, P.; Chauhan, G. S. Modified Pectin-based Polymers as Green Antiscalants for Calcium Sulfate Scale Inhibition. Desalination 2012, 305, 31–37; https://doi.org/10.1016/j.desal.2012.07.042.Search in Google Scholar

22. Salas, H.; Gutiérrez-Bouzán, C.; López-Grimau, V.; Vilaseca, M. Respirometric Study of Optical Brighteners in Textile Wastewater. Materials 2019, 12 (5), 785; https://doi.org/10.3390/ma12050785.Search in Google Scholar PubMed PubMed Central

23. Kumar, M.; Mishra, R. K.; Banthia, A. K. Development of Pectin Based Hydrogel Membranes for Biomedical Applications. Intern. J. Plasti. Technolo 2010, 14 (2), 213–223; https://doi.org/10.1007/s12588-011-0019-5.Search in Google Scholar

24. Guo, Q.; Huang, J.; Li, X. Miscibility of Poly (n-vinyl-2-pyrrolidone) with Poly (Hydroxyether of Phenolphthalein) and Polyacrylonitrile. European polym. j. 1996, 32 (4), 423–426; https://doi.org/10.1016/0014-3057(95)00166-2.Search in Google Scholar

25. Hosseinzadeh, H.; Bahador, N. Novel Cds Quantum Dots Templated Hydrogel Nanocomposites: Synthesis, Characterization, Swelling and Dye Adsorption Properties. J. Mol. Liq. 2017, 240, 630–641; https://doi.org/10.1016/j.molliq.2017.05.129.Search in Google Scholar

26. Bardajee, G. R.; Hooshyar, Z. Interaction of a Novel Starch‐Capped Cds Quantum Dots with Human Serum Albumin and Bovine Serum Albumin. Starch‐Stärke 2016, 68 (3–4), 329–338; https://doi.org/10.1002/star.201500092.Search in Google Scholar

27. Kowalonek, J.; Kaczmarek, H. Studies of pectin/polyvinylpyrrolidone Blends Exposed to Ultraviolet Radiation. European Polym. J. 2010, 46 (2), 345–353; https://doi.org/10.1016/j.eurpolymj.2009.09.015.Search in Google Scholar

28. Mishra, R. K.; Datt, M.; Banthia, A. K. Synthesis and Characterization of pectin/pvp Hydrogel Membranes for Drug Delivery System. Aaps Pharm. 2008, 9 (2), 395–403; https://doi.org/10.1208/s12249-008-9048-6.Search in Google Scholar PubMed PubMed Central

29. Aboelwafa, M. A.; Abdelghany, A. M.; Meikhail, M. S. Preparation, Characterization, and Antibacterial Activity of Zns-np’s Filled polyvinylpyrrolidone/chitosan Thin Films. Biointerf. Res. Appl. Chem. 2021, 14336–14343.10.33263/BRIAC116.1433614343Search in Google Scholar

30. Mishra, S. K.; Srivastava, R. K.; Prakash, S.; Yadav, R. S.; Panday, A. Structural, Optical and Photoconductivity Characteristics of Manganese Doped Cadmium Sulfide Nanoparticles Synthesized by co-precipitation Method. J. alloy. compound. 2012, 513, 118–124; https://doi.org/10.1016/j.jallcom.2011.10.003.Search in Google Scholar

31. Nyamukamba, P.; Moloto, M. J.; Mungondori, H. Visible Light‐Active cds/tio2 Hybrid Nanoparticles Immobilized on Polyacrylonitrile Membranes for the Photodegradation of Dyes in Water. J. Nanotech. 2019 (1); https://doi.org/10.1155/2019/5135618.Search in Google Scholar

32. Sayed, A.; Hany, F.; Abdel-Raouf, M. E. S.; Mahmoud, G. A. Gamma Irradiation Synthesis of Pectin-based Biohydrogels for Removal of Lead Cations from Simulated Solutions. J. Polym. Res. 2022, 29 (9), 372; https://doi.org/10.1007/s10965-022-03219-8.Search in Google Scholar

33. Sadik, W. A. A.; El-Demerdash, A. G. M.; Gabre, H. A.; Hamza, M. E. S. Effective Removal of Malachite Green Dye by eco-friendly pectin-grafted Poly (acrylamide-co-sodium Acrylate) Hydrogel from Aqueous Solutions. Polym. Bull. 2025, 82 (1), 281–311; https://doi.org/10.1007/s00289-024-05502-8.Search in Google Scholar

34. Hou, C.; Ma, K.; Jiao, T.; Xing, R.; Li, K.; Zhou, J.; Zhang, L. Preparation and Dye Removal Capacities of Porous Silver nanoparticle-containing Composite Hydrogels via Poly (Acrylic Acid) and Silver Ions. RSC Adv. 2016, 6 (112), 110799–110807; https://doi.org/10.1039/c6ra23371f.Search in Google Scholar

35. Kumar, N.; Mittal, H.; Parashar, V.; Ray, S. S.; Ngila, J. C. Efficient Removal of Rhodamine 6g Dye from Aqueous Solution Using Nickel Sulphide Incorporated Polyacrylamide Grafted Gum Karaya Bionanocomposite Hydrogel. RSC adv. 2016, 6 (26), 21929–21939; https://doi.org/10.1039/c5ra24299a.Search in Google Scholar

36. Devi, G. K.; Kumar, P. S.; Kumar, K. S. Green Synthesis of Novel Silver Nanocomposite Hydrogel Based on Sodium Alginate as an Efficient Biosorbent for the Dye Wastewater Treatment: Prediction of Isotherm and Kinetic Parameters. Desalina. Water Treat. 2016, 57 (57), 27686–27699; https://doi.org/10.1080/19443994.2016.1178178.Search in Google Scholar

37. Arafa, E. G.; Gawad, O. F. A.; Eldin, Z. E.; Ibrahim, M. M.; Abd-Elghafour, S. A.; Osman, A. H. Sustainable Sodium Alginate Hydrogels Incorporating Banana Leaf Activated Carbon and organo-clay for Enhanced Dye Removal. Sci. Rep. 2025, 15 (1), 16197; https://doi.org/10.1038/s41598-025-99343-8.Search in Google Scholar PubMed PubMed Central

38. Elsayed, A. E.; Attia, S. K.; Rashad, A. M.; Mahmoud, G. A.; Osman, D. I. Synthesis of Dispersed Magnetic fe3o4 Nanohydrogel Based on Gelatine by Gamma Irradiation for Toxic Heavy Metals Removal. J. Inorg. Organomet. Polym. Mater. 2025, 35 (4), 2546–2564; https://doi.org/10.1007/s10904-024-03387-8.Search in Google Scholar

39. Omer, A. M.; Sadik, W. A.; Abbas, R.; Tamer, T. M.; Abd-Ellatif, M. M.; Mohy-Eldin, M. S. Novel amino-ethyl Carboxymethyl Cellulose Crosslinked Ampholyte Hydrogel Development for Methyl Orange Removal from Waste Water. Sci. Rep. 2024, 14 (1), 14701; https://doi.org/10.1038/s41598-024-64245-8.Search in Google Scholar PubMed PubMed Central

40. Fadhillah, F.; Alhamzani, A. G.; Bandar, K. B.; Alshamari, A.; Aljlil, S.; Gadallah, A. G.; Habib, M. A.; Abou-Krisha, M. M.; Abdel-Fatah, M. A. Anionic Hydrogels from Date Palm Waste for Dye Adsorption in Wastewater Treatment. Preprints.org. 2024, 1–24; https://doi.org/10.20944/preprints202405.1464.v1.Search in Google Scholar

41. Khan, S.; Rahman, N. U.; Alam, S.; Zahoor, M.; Shah, L. A.; Umar, M. N.; Ullah, R. Synthesis of Poly (gg-co-aam-co-maa), a Terpolymer Hydrogel for the Removal of Methyl Violet and Fuchsin Basic Dyes from Aqueous Solution. ACS omega 2024, 9 (7), 7692–7704; https://doi.org/10.1021/acsomega.3c07118.Search in Google Scholar PubMed PubMed Central

42. Nguyen, D. K. V.; Thuc, C. N. H.; Chi Nhan Ha Thuc Synthesis and Characterization of Oxidized starch-montmorillonite Composite for Efficient Removal of Crystal Violet Dye from Aqueous Solutions. J. Techni. Edu. Sci. 2024, 19, 92–100; https://doi.org/10.54644/jte.2024.1730.Search in Google Scholar
Received: 2025-09-18
Accepted: 2026-01-23
Published Online: 2026-02-05

© 2026 Walter de Gruyter GmbH, Berlin/Boston

https://doi.org/10.1515/ract-2025-0093
Keywords for this article
hydrogel; CdS; pectin and gamma radiation
Downloaded on 29.4.2026 from https://www.degruyterbrill.com/document/doi/10.1515/ract-2025-0093/html?lang=en
Scroll to top button