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Kim, Y. Hydrogels and Graphene Quantum Dots. Encyclopedia. Available online: https://encyclopedia.pub/entry/15033 (accessed on 15 September 2024).
Kim Y. Hydrogels and Graphene Quantum Dots. Encyclopedia. Available at: https://encyclopedia.pub/entry/15033. Accessed September 15, 2024.
Kim, Yuna. "Hydrogels and Graphene Quantum Dots" Encyclopedia, https://encyclopedia.pub/entry/15033 (accessed September 15, 2024).
Kim, Y. (2021, October 14). Hydrogels and Graphene Quantum Dots. In Encyclopedia. https://encyclopedia.pub/entry/15033
Kim, Yuna. "Hydrogels and Graphene Quantum Dots." Encyclopedia. Web. 14 October, 2021.
Hydrogels and Graphene Quantum Dots
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The graphene quantum dot (GQD), unlike the other graphene derivatives, is known to have distinctive optical properties showing size and edge-dependent fluorescence properties

graphene quantum dots hydrogel organic-inorganic nanostructures

1. Introduction

Hydrogels, neither classified as completely liquid nor as solid state, are hydrophilic polymer networks which can absorb water to their porous networks. They have been of great interest to researchers in various applications such as polymer contact lenses and tissue engineering. The three-dimensional porous network structure can be modulated by controlling the ratio of monomers and crosslinking agents during polymerization. Moreover, the stimulus-responsive volume changes sensitive to temperature, pH, solvent, and electric field enables them to be applied in various biomedical applications [1][2][3][4][5][6][7][8][9][10][11]. In addition, the excellent optical and mechanical properties of the hydrogels can be applied to multifunctional contact lenses [12][13][14].
However, there have been some limitations of hydrogels for practical use. Firstly, they show poor mechanical properties with low tensile/compression strength and toughness. [5][15][16] Second, the conventional photoinitiators needed for hydrogel photopolymerization have an innate toxicity, limiting its usage in biological applications [17][18]. Thus, several methods have been proposed to synthesize hydrogels with enhanced mechanical properties and biocompatibility by hybridizing different nanomaterials [19][20][21][22][23][24]. Several carbon-based nanocomposites, such as carbon nanotubes, graphene oxides (GOs), or functionalized graphene sheets, have been implemented to improve the mechanical properties. However, these carbon nanomaterials lack the ability to function as photoinitiators, and therefore, additional toxic substances need to be employed to generate the radicals to trigger the polymerization [16][22][25][26].
The photoinitiator should be a photosensitive molecule with an absorption wavelength range adequate for the initiation of polymerization reaction, and the absorbed photon should possess sufficient energy to generate free radicals. In this process, the functional groups on the initiator can expedite the polymerization reaction [27][28][29]. The graphene quantum dot (GQD), unlike the other graphene derivatives, is known to have distinctive optical properties showing size and edge-dependent fluorescence properties [24][30][31][32][33][34][35][36][37][38]. It shows wide absorption spectra ranging from UV to visible wavelengths. Furthermore, GQDs are expected to show better biocompatibility than other inorganic semiconductor nanoparticles such as TiO2 and ZnO when they are used solely or as a composite [32][39][40][41][42][43].
Thus, we employed the dual functionality of GQDs as photoinitiators for the polymerization of polyacrylamide hydrogels and mechanical reinforcers of as-synthesized hydrogel networks (Scheme 1). They acted effectively even with sunlight as photoinitiators due to their broad absorption range, and achieved high Young’s moduli by up to 50 times. The swelling ratio was similar or slightly increased compared to the hydrogel fabricated by the conventional photoinitiator. Finally, we demonstrated a potential application for contact lenses with high transmittance (≥90%).
Scheme 1. Overall synthetic process of GQD-mediated hydrogel (GQDGel). The reactant (monomer and crosslinker) are dissolved in deionized water, followed by addition of initiator (GQD) and catalyst. After exposure to sunlight or UV, the final product, polyacrylamide hydrogel is synthesized.

2. Synthesis of GQDs

Graphene quantum dots (GQDs) were synthesized by following the previously reported method [32][40][41][44]. In brief, 0.9 g of carbon fiber was added into an acidic mixture of concentrated H2SO4 and HNO3 in 3:1 (v/v) ratio. The mixed solution was sonicated for two hours and stirred for 24 h at 100 and 120 °C. The mixture was cooled and diluted with deionized (DI) water. The final product was then further dialyzed (molecular weight cut-off: 1 kDa) for 3 days, followed by lyophilization. Then, 0.01 g of as-fabricated GQD was mixed with 10 mL of DI water for its usage in hydrogel.

3. Characterization of GQDs

The GQD layers were characterized using various microscopic and spectroscopic techniques. Raman analysis was performed by inVia Raman Microscope (Renishaw, Gloucestershire, UK) An absorbance spectrum was obtained by UV−Vis-NIR spectrophotometer (S-3100, Scinco, Seoul, Korea). FT-IR spectra were acquired by FT-IR spectrophotometer (Nicolet 6700, Thermo Scientific, Waltham, MA, USA). The photoluminescence characterization was performed by the fluorescence spectrometer (FP-8300, Jasco Inc., Easton, MD, USA) with Xe lamp as the source of excitation.

References

  1. Wang, H.; Heilshorn, S.C. Adaptable Hydrogel Networks with Reversible Linkages for Tissue Engineering. Adv. Mater. 2015, 27, 3717–3736.
  2. Van Vlierberghe, S.; Dubruel, P.; Schacht, E. Biopolymer-Based Hydrogels as Scaffolds for Tissue Engineering Applications: A Review. Biomacromolecules 2011, 12, 1387–1408.
  3. Tomczykowa, M.; Plonska-Brzezinska, M.E. Conducting Polymers, Hydrogels and their Composites: Preparation, Properties and Bioapplications. Polymers 2019, 11, 350.
  4. Javadi, M.; Gu, Q.; Naficy, S.; Farajikhah, S.; Crook, J.M.; Wallace, G.G.; Beirne, S.; Moulton, S.E. Conductive Tough Hydrogel for Bioapplications. Macromol. Biosci. 2018, 18, 1700270.
  5. Li, J.; Mooney, D.J. Designing Hydrogels for Controlled Drug Delivery. Nat. Rev. Mater. 2016, 1, 16071.
  6. Hamidi, M.; Azadi, A.; Rafiei, P. Hydrogel Nanoparticles in Drug Delivery. Adv. Drug Deliv. Rev. 2008, 60, 1638–1649.
  7. Hoffman, A.S. Hydrogels for Biomedical Applications. Adv. Drug Deliv. Rev. 2012, 64, 18–23.
  8. Hunt, J.A.; Chen, R.; van Veen, T.; Bryan, N. Hydrogels for Tissue Engineering and Regenerative Medicine. J. Mater. Chem. B 2014, 2, 5319–5338.
  9. Nguyen, K.T.; West, J.L. Photopolymerizable Hydrogels for Tissue Engineering Applications. Biomaterials 2002, 23, 4307–4314.
  10. Rosiak, J.; Burczak, K.; Pekala, W. Polyacrylamide Hydrogels as Sustained-Release Drug Delivery Dressing Materials. Radiat. Phys. Chem. 1983, 22, 907–915.
  11. Billiet, T.; Vandenhaute, M.; Schelfhout, J.; Van Vlierberghe, S.; Dubruel, P. A Review of Trends and Limitations in Hydrogel-Rapid Prototyping for Tissue Engineering. Biomaterials 2012, 33, 6020–6041.
  12. Chatterjee, S.; Upadhyay, P.; Mishra, M.; Srividya, M.; Akshara, M.R.; Kamali, N.; Zaidi, Z.S.; Iqbal, S.F.; Misra, S.K. Advances in Chemistry and Composition of Soft Materials for Drug Releasing Contact Lenses. RSC Adv. 2020, 10, 36751–36777.
  13. Moreddu, R.; Vigolo, D.; Yetisen, A.K. Contact Lens Technology: From Fundamentals to Applications. Adv. Healthc. Mater. 2019, 8, 1900368.
  14. Driest, P.J.; Allijn, I.E.; Dijkstra, D.J.; Stamatialis, D.; Grijpma, D.W. Poly(Ethylene Glycol)-Based Poly(Urethane Isocyanurate) Hydrogels for Contact Lens Applications. Polym. Int. 2020, 69, 131–139.
  15. Gong, J.P.; Katsuyama, Y.; Kurokawa, T.; Osada, Y. Double-Network Hydrogels with Extremely High Mechanical Strength. Adv. Mater. 2003, 15, 1155–1158.
  16. Zhang, L.; Wang, Z.; Xu, C.; Li, Y.; Gao, J.; Wang, W.; Liu, Y. High Strength Graphene Oxide/Polyvinyl Alcohol Composite Hydrogels. J. Mater. Chem. 2011, 21, 10399–10406.
  17. Janney, M.A.; Omatete, O.O.; Walls, C.A.; Nunn, S.D.; Ogle, R.J.; Westmoreland, G. Development of Low-Toxicity Gelcasting Systems. J. Am. Ceram. Soc. 1998, 81, 581–591.
  18. Williams, C.G.; Malik, A.N.; Kim, T.K.; Manson, P.N.; Elisseeff, J.H. Variable Cytocompatibility of Six Cell Lines with Photoinitiators Used for Polymerizing Hydrogels and Cell Encapsulation. Biomaterials 2005, 26, 1211–1218.
  19. Arno, M.C.; Inam, M.; Weems, A.C.; Li, Z.; Binch, A.L.; Platt, C.I.; Richardson, S.M.; Hoyland, J.A.; Dove, A.P.; O’Reilly, R.K. Exploiting the Role of Nanoparticle Shape in Enhancing Hydrogel Adhesive and Mechanical Properties. Nat. Commun. 2020, 11, 1420.
  20. Huang, Z.-Y.; Barber, T.; Mills, G.; Morris, M.-B. Heterogeneous Photopolymerization of Methyl Methacrylate Initiated by Small ZnO Particles. J. Phys. Chem. 1994, 98, 12746–12752.
  21. Thoniyot, P.; Tan, M.J.; Karim, A.A.; Young, D.J.; Loh, X.J. Nanoparticle–Hydrogel Composites: Concept, Design, and Applications of these Promising, Multi-Functional Materials. Adv. Sci. 2015, 2, 1400010.
  22. Moniruzzaman, M.; Winey, K.I. Polymer Nanocomposites Containing Carbon Nanotubes. Macromolecules 2006, 39, 5194–5205.
  23. Zhang, D.; Yang, J.; Bao, S.; Wu, Q.; Wang, Q. Semiconductor Nanoparticle-Based Hydrogels Prepared via Self-Initiated Polymerization under Sunlight, even Visible Light. Sci. Rep. 2013, 3, 1399.
  24. Ruiz-Palomero, C.; Benítez-Martínez, S.; Soriano, M.L.; Valcárcel, M. Fluorescent nanocellulosic hydrogels based on graphene quantum dots for sensing laccase. Anal. Chim. Acta 2017, 974, 93–99.
  25. Chatterjee, S.; Lee, M.W.; Woo, S.H. Enhanced Mechanical Strength of Chitosan Hydrogel Beads by Impregnation with Carbon Nanotubes. Carbon 2009, 47, 2933–2936.
  26. Bai, H.; Sheng, K.; Zhang, P.; Li, C.; Shi, G. Graphene Oxide/Conducting Polymer Composite Hydrogels. J. Mater. Chem. 2011, 21, 18653–18658.
  27. Ge, J.; Lan, M.; Zhou, B.; Liu, W.; Guo, L.; Wang, H.; Jia, Q.; Niu, G.; Huang, X.; Zhou, H.; et al. A Graphene Quantum Dot Photodynamic Therapy Agent with High Singlet Oxygen Generation. Nat. Commun. 2014, 5, 4596.
  28. Zhou, Y.; Sun, H.; Wang, F.; Ren, J.; Qu, X. How Functional Groups Influence the ROS Generation and Cytotoxicity of Graphene Quantum Dots. Chem. Commun. 2017, 53, 10588–10591.
  29. Chatani, S.; Kloxin, C.J.; Bowman, C.N. The Power of Light in Polymer Science: Photochemical Processes to Manipulate Polymer Formation, Structure, and Properties. Polym. Chem. 2014, 5, 2187–2201.
  30. Tajik, S.; Dourandish, Z.; Zhang, K.; Beitollahi, H.; Van Le, Q.; Jang, H.W.; Shokouhimehr, M. Carbon and Graphene Quantum Dots: A Review on Syntheses, Characterization, Biological and Sensing Applications for Neurotransmitter Determination. RSC Adv. 2020, 10, 15406–15429.
  31. Moon, B.J.; Lee, K.S.; Shim, J.; Park, S.; Kim, S.H.; Bae, S.; Park, M.; Lee, C.-L.; Choi, W.K.; Yi, Y.; et al. Enhanced Photovoltaic Performance of Inverted Polymer Solar Cells Utilizing Versatile Chemically Functionalized Graphene Quantum Dot Monolayer. Nano Energy 2016, 20, 221–232.
  32. Peng, J.; Gao, W.; Gupta, B.K.; Liu, Z.; Romero-Aburto, R.; Ge, L.; Song, L.; Alemany, L.B.; Zhan, X.; Gao, G.; et al. Graphene Quantum Dots Derived from Carbon Fibers. Nano Lett. 2012, 12, 844–849.
  33. Konstantatos, G.; Badioli, M.; Gaudreau, L.; Osmond, J.; Bernechea, M.; De Arquer, F.P.G.; Gatti, F.; Koppens, F.H. Hybrid Graphene–Quantum Dot Phototransistors with Ultrahigh Gain. Nat. Nanotechnol. 2012, 7, 363–368.
  34. Li, M.; Chen, T.; Gooding, J.J.; Liu, J. Review of Carbon and Graphene Quantum Dots for Sensing. ACS Sens. 2019, 4, 1732–1748.
  35. Zhang, Z.; Chang, K.; Peeters, F. Tuning of Energy Levels and Optical Properties of Graphene Quantum Dots. Phys. Rev. B 2008, 77, 235411.
  36. Das, P.; Ganguly, S.; Banerjee, S.; Das, N.C. Graphene based emergent nanolights: A short review on the synthesis, properties and application. Res. Chem. Intermed. 2019, 45, 3823–3853.
  37. Ganguly, S.; Das, P.; Itzhaki, E.; Hadad, E.; Gedanken, A.; Margel, S. Microwave-Synthesized Polysaccharide-Derived Carbon Dots as Therapeutic Cargoes and Toughening Agents for Elastomeric Gels. ACS Appl. Mater. Interfaces 2020, 12, 51940–51951.
  38. Khabibullin, A.; Alizadehgiashi, M.; Khuu, N.; Prince, E.; Tebbe, M.; Kumacheva, E. Injectable Shear-Thinning Fluorescent Hydrogel Formed by Cellulose Nanocrystals and Graphene Quantum Dots. Langmuir 2017, 33, 12344–12350.
  39. Zhang, H.; Ba, S.; Yang, Z.; Wang, T.; Lee, J.Y.; Li, T.; Shao, F. Graphene Quantum Dot-Based Nanocomposites for Diagnosing Cancer Biomarker APE1 in Living Cells. ACS Appl. Mater. Interfaces 2020, 12, 13634–13643.
  40. Kang, I.; Yoo, J.M.; Kim, D.; Kim, J.; Cho, M.K.; Lee, S.-E.; Kim, D.J.; Lee, B.-C.; Lee, J.Y.; Kim, J.-J.; et al. Graphene Quantum Dots Alleviate Impaired Functions in Niemann-Pick Disease Type C In Vivo. Nano Lett. 2021, 21, 2339–2346.
  41. Lee, B.-C.; Lee, J.Y.; Kim, J.; Yoo, J.M.; Kang, I.; Kim, J.-J.; Shin, N.; Kim, D.J.; Choi, S.W.; Kim, D.; et al. Graphene Quantum Dots as Anti-Inflammatory Therapy for Colitis. Sci. Adv. 2020, 6, eaaz2630.
  42. Kim, D.; Yoo, J.M.; Hwang, H.; Lee, J.; Lee, S.H.; Yun, S.P.; Park, M.J.; Lee, M.; Choi, S.; Kwon, S.H.; et al. Graphene Quantum Dots Prevent α-Synucleinopathy in Parkinson’s Disease. Nat. Nanotechnol. 2018, 13, 812–818.
  43. Shen, J.; Zhu, Y.; Yang, X.; Li, C. Graphene Quantum Dots: Emergent Nanolights for Bioimaging, Sensors, Catalysis and Photovoltaic Devices. Chem. Commun. 2012, 48, 3686–3699.
  44. Lee, B.-C.; Lee, J.Y.; Kim, J.; Shin, N.; Yoo, J.M.; Kang, I.; Kim, J.-J.; Lee, S.-E.; Kim, D.; Choi, S.W.; et al. Oral Administration of Microbiome-Friendly Graphene Quantum Dots as Therapy for Colitis. 2D Mater. 2021, 8, 025036.
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