Author(s): Rangu Nirmala, Billa Sravani, V. Umamaheshwara Rao

Email(s): rangunirmala@gmail.com

DOI: 10.52711/0975-4377.2026.00022   

Address: Rangu Nirmala*, Billa Sravani, V. Umamaheshwara Rao
1Department of Pharmaceutics, CMR College of Pharmacy, Kandlakoya, Medchal, Hyderabad, 501401, India.
*Corresponding Author

Published In:   Volume - 18,      Issue - 2,     Year - 2026


ABSTRACT:
Hydrogels are three-dimensional, hydrophilic polymeric networks that can absorb large quantities of water or biological fluids without compromising their structural integrity. They can be used in environmental research, biotechnology, agriculture, and medicine as they offer specific characteristics like significant porosity, tunable mechanical strength. This review provides an overview of types of hydrogels, their synthesis methods, and smart hydrogels. Hydrogels can be classified as natural, synthetic, or hybrid depending on their origin, and cross-linking can happen as a result of chemical or physical interactions. The physical cross-linking method, chemical cross-linking method, and irradiation-based cross-linking method are the common methods used in the synthesis of hydrogels. A significant development in the field is the use of smart hydrogels, which react to environmental stimuli including temperature, pH, light, and biomolecular interactions. These adaptable systems have great potential for biosensing, tissue engineering, wound care, and controlled medication administration.


Cite this article:
Rangu Nirmala, Billa Sravani, V. Umamaheshwara Rao. A Comprehensive Review on Hydrogels: Classification, Synthesis and Smart Hydrogels. Research Journal of Pharmaceutical Dosage Forms and Technology. 2026; 18(2):141-6. doi: 10.52711/0975-4377.2026.00022

Cite(Electronic):
Rangu Nirmala, Billa Sravani, V. Umamaheshwara Rao. A Comprehensive Review on Hydrogels: Classification, Synthesis and Smart Hydrogels. Research Journal of Pharmaceutical Dosage Forms and Technology. 2026; 18(2):141-6. doi: 10.52711/0975-4377.2026.00022   Available on: https://www.rjpdft.com/AbstractView.aspx?PID=2026-18-2-8


REFERENCES:
1.    Earle Radha Rani, M. Ramadevi, Ayalasomayajula Lakshmi Usha. An Overview on Hydrophilic Three-Dimensional Networks: Hydrogels. Asian Journal of Pharmaceutical Research. 2021; 11(1): 23-28. https://doi.org/10.5958/2231-5691.2021.00006.X.  
2.    Nandhakumar L, Dharmamoorthy G, Chandrasekaran S. Hydrogels: a multifaceted contemporary approaches and advancements. Research Journal of Pharmacy and Technology. 2011; 4(11): 1658-1662. 
3.    Jakkannavar A, Patil S, Patil M. Polymer-based hydrogels as enhanced drug delivery system. Asian Journal of Research in Chemistry. 2024; 17(6): 392–398. https://doi.org/10.52711/0974-4150.2024.00065. 
4.    Abhishek Kanugo, Aparajita Chakravarti. Recent Advances in the Biomedical Applications of Hydrogels. Asian Journal of Pharmacy and Technology. 2025; 15(3): 289-295. https://doi.org/10.52711/2231-5713.2025.00044. 
5.    Reena Bhadani, U.K. Mitra. Synthesis and Characterization of Polyacrylamide Hydrogels. Asian Journal of Research in Chemistry. 2014;7(3):345–348.
6.    Singh D, Daharwal SJ, Rawat M. Hydrogels: A potent carrier in wound healing. Research Journal of Pharmacy and Technology. 2008; 1(1): 6–13.
7.    Parikshit Pise. A review on nanoparticle-loaded hydrogels for extended drug release. Asian Journal of Pharmacy and Technology. 2024; 14(1): 55–58. https://doi.org/10.52711/2231-5713.2024.00011.  
8.    Ho TC, Chang CC, Chan HP, Chung TW, Shu CW, Chuang KP, Duh TH, Yang MH, Tyan YC. Hydrogels: properties and applications in biomedicine. Molecules. 2022 May 2; 27(9): 2902. https://doi.org/10.3390/molecules27092902.
9.    Jayesh S. Gharat, Yogita V. Dalvi. Compressive Review on Hydrogel. Asian Journal of Pharmaceutics and Technology. 2018; 8(3): 172–181. https://doi.org/10.5958/2231-5713.2018.00028.4.  
10.    Akash Jakkannavar, Sneha Patil, Mrityunjaya Patil. Polymer-Based Hydrogels as Enhanced Drug Delivery System. Asian Journal of Research in Chemistry. 2024; 17(6): 392-398. https://doi.org/10.52711/0974-4150.2024.00065. 
11.    Vinutha BV, Sheeba FR. pH-sensitive hydrogel: a review. Research Journal of Pharmaceutical Dosage Forms and Technology. 2023; 15(3): 189–197. https://doi.org/10.52711/0975-4377.2023.00031. 
12.    Bao Z, Xian C, Yuan Q, Liu G, Wu J. Natural polymer‐based hydrogels with enhanced mechanical performances: preparation, structure, and property. Advanced Healthcare Materials. 2019; 8(17): 1900670. https://doi.org/10.1002/adhm.201900670.
13.    Singhal R, Gupta K. A review: Tailor-made hydrogel structures (classifications and synthesis parameters). Polymer-Plastics Technology and Engineering. 2016; 55(1): 54-70. https://doi.org/10.1080/03602559.2015.1050520.
14.    Palacio DA, Urbano BF, Palencia M, Rivas BL. Preparation of alkylated chitosan-based polyelectrolyte hydrogels: The effect of monomer charge on polymerization. European Polymer Journal. 2019; 118: 551-560. https://doi.org/10.1016/j.eurpolymj.2019.06.024.
15.    Ahmad Z, Salman S, Khan SA, Amin A, Rahman ZU, Al-Ghamdi YO, Akhtar K, Bakhsh EM, Khan SB. Versatility of hydrogels: from synthetic strategies, classification, and properties to biomedical applications. Gels. 2022 Mar 7; 8(3): 167. https://doi.org/10.3390/gels8030167. 
16.    Priya AS, Premanand R, Ragupathi I, Bhaviripudi VR, Aepuru R, Kannan K, Shanmugaraj K. Comprehensive Review of Hydrogel Synthesis, Characterization, and Emerging Applications. Journal of Composites Science. 2024; 8(11): 57. https://doi.org/10.3390/jcs8110457. 
17.    Zhang Y, Hu C, Xiang X, Diao Y, Li B, Shi L, Ran R. Self-healable, tough and highly stretchable hydrophobic association/ionic dual physically cross-linked hydrogels. RSC advances. 2017; 7(20): 12063-73. https://doi.org/10.1039/C7RA00055C. 
18.    Jiang C. Design Principles and Frontiers of Applications for Thermo-Responsive and Self-Healing Hydrogels. Applied and Computational Engineering. 2025 Jan 7; 123: 262-71. https://doi.org/10.54254/2755-2721/2025.19710.
19.    Maitra J, Shukla VK. Cross-linking in hydrogels: a review. American Journal of Polymer Science. 2014; 4(2): 25–31. 
20.    Sun, X.F. Xie, Y, Shan, S. Li, W. Sun, L. Chemically crosslinked xylan/Graphene oxide composite hydrogel for copper ions removal. Journal of Polymers and Environment. 2022; 30: 3999–4013. https://doi.org/10.1007/s10924-022-02475-5. 
21.    Tan, H. Chu, C.R. Payne, K.A. Marra, K.G. Injectable in situ forming biodegradable chitosan–hyaluronic acid based hydrogels for cartilage tissue engineering. Biomaterials 2009, 30, 2499–2506. https://doi.org/10.1016/j.biomaterials.2008.12.080. 
22.    Kausar, A. Nanocarbon in Polymeric Nanocomposites Hydrogel-Design and Multi-Functional Tendencies. Polymers-Plastics Technology and Materials. 2020; 59: 1505–1521. https://doi.org/10.1080/25740881.2020.1757106. 
23.    Nguyen, N.T.P.; Nguyen, L.V.H.; Thanh, N.T.; Van Toi, V.; Quyen, T.N.; Tran, P.A.; Wang, H.M.D.; Nguyen, T.H. Stabilization of silver nanoparticles in chitosan and gelatin hydrogel and its applications. Matter. Letters. 2019; 248: 241–245. https://doi.org/10.1016/j.matlet.2019.03.103. 
24.    Mahdi Karimi, Amir Ghasemi, Parham Sahandi Zangabad, Reza Rahighi, S. Masoud Moosavi Basri, Hadi Mirshekari, Mohammad Amiri, Zahra Shafaei Pishabad, Ali Aslani, Mohammad Bozorgomid, Debabrata Ghosh, Ali Beyzavi, Ali Vaseghi, Ali R. Aref, Leila Haghani, Shahram Bahrami, Michael R. Hamblin. Smart micro/nanoparticles in stimulus-responsive drug/gene delivery systems. Chemical Society Reviews. 2016; 45: 1457–1501. https://doi.org/10.1039/C5CS00798D. 
25.    Rizwan M, Yahya R, Hassan A, Yar M, Azzahari AD, Selvanathan V, Sonsudin F, Abouloula CN. pH sensitive hydrogels in drug delivery: Brief history, properties, swelling, and release mechanism, material selection and applications. Polymers. 2017; 9(4): 137. https://doi.org/10.3390/polym9040137.  
26.    Du H, Liu M, Yang X, Zhai G. The design of pH-sensitive chitosan-based formulations for gastrointestinal delivery. Drug Discovery Today. 2015;20(8):1004–1011.
27.    Zhao Y, Lei M, Liu SX, et al. Smart hydrogel-based optical fiber SPR sensor for pH measurements. Sensors and Actuators B: Chemical. 2018; 261: 226–232. https://doi.org/10.1016/j.snb.2018.01.120. 
28.    Rafael D, Melendres MMR, Andrade F, Montero S, Martinez-Trucharte F, Vilar-Hernandez M, Durán-Lara EF, Schwartz S Jr, Abasolo I. Thermo-responsive hydrogels for cancer local therapy: Challenges and state-of-art. International Journal of Pharmaceutics. 2021; 606: 120954. https://doi.org/10.1016/j.ijpharm.2021.120954. 
29.    Bordbar-Khiabani A, Gasik M. Smart hydrogels for advanced drug delivery systems. International Journal of Molecular Sciences. 2022; 23(7): 3665.
30.    Huang H, Qi X, Chen Y, Wu Z. Thermo-sensitive hydrogels for delivering biotherapeutic molecules: A review. Saudi Pharmaceutical Journal. 2019; 27(7): 990-9. https://doi.org/10.1016/j.jsps.2019.08.001. 
31.    Byeongmoon J, Sung WK, You HB. Thermosensitive sol–gel reversible hydrogels. Advanced Drug Delivery Reviews. 2012; 64: 154-62. https://doi.org/10.1016/S0169-409X(01)00242-3. 
32.    Zhang G, Chen Y, Deng Y, Ngai T, Wang C. Dynamic supramolecular hydrogels: Regulating hydrogel properties through self-complementary quadruple hydrogen bonds and thermo-switch. ACS Macro Letters. 2017; 6(7): 641–646. https://doi.org/10.1021/acsmacrolett.7b00275.
33.    Carlini AS, Adamiak L, Gianneschi NC. Biosynthetic polymers as functional materials. Macromolecules. 2016; 49(12): 4379–4394. https://doi.org/10.1021/acs.macromol.6b00439. 
34.    Callmann CE, Barback CV, Thompson MP, Hall DJ, Mattrey RF, Gianneschi NC. Therapeutic enzyme-responsive nanoparticles for targeted delivery and accumulation in tumors. Advanced Materials. 2015; 27(31): 4611–4615. https://doi.org/10.1002/adma.201501803. 
35.    Nam M, Lee JW, Cha GD. Biomedical Application of Enzymatically Crosslinked Injectable Hydrogels. Gels. 2024; 10(10): 640. https://doi.org/10.3390/gels10100640. 
36.    Liu J, Yi X, Zhang J, Yao Y, Panichayupakaranant P, Chen H. Recent advances in the drugs and glucose-responsive drug delivery systems for the treatment of diabetes: a systematic review. Pharmaceutics. 2024; 16(10): 1343. https://doi.org/10.3390/pharmaceutics16101343. 
37.    Truong VX, Li F, Ercole F, Forsythe JS. Wavelength-selective coupling and decoupling of polymer chains via reversible [2+ 2] photocycloaddition of styrylpyrene for construction of cytocompatible photodynamic hydrogels. ACS Macro Letters. 2018 Mar 26;7(4):464-9.
38.    Xing Y, Zeng B, Yang W. Light responsive hydrogels for controlled drug delivery. Frontiers in Bioengineering and Biotechnology. 2022 Dec 16; 10: 1075670.
39.    Li L, Scheiger JM, Levkin PA. Design and applications of photoresponsive hydrogels. Advanced Materials. 2019 Jun; 31(26): 1807333.

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