Influence of radical initiators in gold catalysis: Evidence supporting trapping of radicals derived from azobis(isobutyronitrile) by gold halides

[EN] Gold halides (AuCl3, HAuCl4, and AuCl) efficiently trap the radicals generated in the room-temperature photolysis of azobis(isobutyronitrile) (AIBN) to give an organogold H[(CH3)(2)CCN](2)AuCl2 compound that has been characterized by spectroscopy. The characteristic features of the organogold are a quaternary carbon at 100 ppm on C-13 NMR and a HR-MS peak with a molecular formula Of C8H13N2AuCl. Catalytic data for cyclohexene aerobic oxidation confirms the beneficial influence of the presence of AlBN on the catalytic activity of Au/CeO2C.Alvaro Rodríguez, MM.; Aprile ., C.; Corma Canós, A.; Ferrer Ribera, RB.; García Gómez, H. (2006). Influence of radical initiators in gold catalysis: Evidence supporting trapping of radicals derived from azobis(isobutyronitrile) by gold halides. Journal of Catalysis. 245(1):249-252. doi:10.1016/j.jcat.2006.10.003S249252245

Metal-Organic Frameworks as Photocatalysts for Solar-Driven Overall Water Splitting

[EN] Metal-organic frameworks (MOFs) have been frequently used as photocatalysts for the hydrogen evolution reaction (HER) using sacrificial agents with UV-vis or visible light irradiation. The aim of the present review is to summarize the use of MOFs as solar-driven photocatalysts targeting to overcome the current efficiency limitations in overall water splitting (OWS). Initially, the fundamentals of the photocatalytic OWS under solar irradiation are presented. Then, the different strategies that can be implemented on MOFs to adapt them for solar photocatalysis for OWS are discussed in detail. Later, the most active MOFs reported until now for the solar-driven HER and/or oxygen evolution reaction (OER) are critically commented. These studies are taken as precedents for the discussion of the existing studies on the use of MOFs as photocatalysts for the OWS under visible or sunlight irradiation. The requirements to be met to use MOFs at large scale for the solar-driven OWS are also discussed. The last section of this review provides a summary of the current state of the field and comments on future prospects that could bring MOFs closer to commercial application.S.N. is gracious for the financial support from Grant PID2021-123856OB-I00 funded by MCIN/AEI/10.13039/501100011033 and by "ERDF A way of making Europe. The MOF2H2 project receives funding from the European Union Horizon Europe research and innovation programme under Grant Agreement No101084131. The METHASOL project receives funding from the European Union Horizon 2020 research and innovation programme under Grant Agreement No101022649. A.D. thanks the Universitat Politecnica de Valencia for financial assistance through Maria Zambrano. H.G. is thankful for financial support by the Spanish Ministry of Science and Innovation (Severo Ochoa) and the Generalitat Valenciana (Prometeo2021-038). H.G. is also gracious for the financial support from Grant PID2021-126071OB-C21 funded by MCIN/AEI/10.13039/501100011033 and by "ERDF A way of making Europe."Navalón Oltra, S.; Amarajothi, DM.; Alvaro Rodríguez, MM.; Ferrer Ribera, RB.; García Gómez, H. (2023). Metal-Organic Frameworks as Photocatalysts for Solar-Driven Overall Water Splitting. Chemical Reviews. 123:445-490. https://doi.org/10.1021/acs.chemrev.2c0046044549012

Bifunctional metal-organic frameworks for the hydrogenation of nitrophenol using methanol as the hydrogen source

[EN] This work reports the reduction of 4-nitrophenol to 4-aminophenol using UiO-66(Zr) as a bifunctional photocatalyst and hydrogenation catalyst using methanol as the hydrogen source. In particular, a series of UiO-66(Zr)-X (X: NH2, NO2 and H) and MIL-125(Ti)-NH2 catalysts have been screened as bifunctional catalysts for this process. UiO-66(Zr)-NH2 was found to be the most active material to promote light-assisted nitro hydrogenation under both UV-Vis and simulated sunlight irradiation. The tandem reaction occurs via hydrogen generation from a water/methanol mixture in the first step and, then, reduction of 4-nitrophenol to 4-aminophenol. UiO-66(Zr)-NH2 acts as a truly heterogeneous catalyst and can be reused several times without significant loss of activity, maintaining its crystallinity. This work shows the possibility of using MOFs as solar-driven bifunctional catalysts to promote the hydrogenation of organic compounds using methanol as the hydrogen source.S. N. acknowledges the financial support by the Fundacion Ramon Areces (XVIII Concurso Nacional para la Adjudicacion de Ayudas a la Investigacion en Ciencias de la Vida y de la Materia, 2016), Ministerio de Ciencia, Innovacion y Universidades RTI 2018-099482-A-I00 project and Generalitat Valenciana grupos de investigacion consolidables 2019 (ref: AICO/2019/214) project. Financial support by the Spanish Ministry of Economy and Competitiveness (Severo Ochoa and RTI2018-098237-B-C21) and Generalitat Valenciana (Prometeo 2017-083) is also gratefully acknowledged.Melillo, A.; García-Vallés, C.; Ferrer Ribera, RB.; Alvaro Rodríguez, MM.; Navalón Oltra, S.; García Gómez, H. (2021). Bifunctional metal-organic frameworks for the hydrogenation of nitrophenol using methanol as the hydrogen source. Organic & Biomolecular Chemistry. 19(4):794-800. https://doi.org/10.1039/d0ob01686aS79480019

Gas-Phase Photochemical Overall H2 S Splitting by UV Light Irradiation

[EN] Splitting of hydrogen sulfide is achieved to produce valueadded chemicals. Upon irradiation at 254 nm in the gas phase and in the absence of catalysts or photocatalysts at near room temperature, H2S splits into stoichiometric amounts of H2 and S with a quantum efficiency close to 50%. No influence of the presence of CH4 and CO2 (typical components in natural gas and biogas in which H2S is an unwanted component) on the efficiency of overall H2S splitting was observed. A mechanism for the H2 and S formation is proposed.Financial support by the Spanish Ministry of Economy and R1) and Generalitat Valenciana (Prometeo 2013-014) is gratefully acknowledged. Thanks are due to Dr. J. A. Agullo-Macia for performing a preliminary experiment.Garcia-Baldovi, H.; Albero-Sancho, J.; Ferrer Ribera, RB.; Mateo-Mateo, D.; Alvaro Rodríguez, MM.; García Gómez, H. (2017). Gas-Phase Photochemical Overall H2 S Splitting by UV Light Irradiation. ChemSusChem. 10(9):1996-2000. https://doi.org/10.1002/cssc.201700294S1996200010

High-Intensity Focused Ultrasound in Small Renal Masses

High-intensity focused ultrasound (HIFU) competes with radiofrequency and cryotherapy for the treatment of small renal masses as a third option among ablative approaches. As an emerging technique, its possible percutaneous or laparoscopic application, low discomfort to the patient and the absence of complications make this technology attractive for the management of small renal masses. This manuscript will focus on the principles, basic research and clinical applications of HIFU in small renal masses, reviewing the present literature. Therapeutic results are controversial and from an clinical view, HIFU must be considered a technique under investigation at present time. Further research is needed to settle its real indications in the management of small renal masses; maybe technical improvements will certainly facilitate its use in the management of small renal masses in the near future

Bimetallic iron-copper oxide nanoparticles supported on nanometric diamond as efficient and stable sunlight-assisted Fenton photocatalyst

[EN] Bimetallic iron and copper oxide nanoparticles (NPs) supported on hydroxylated diamond (D3) exhibits an improved activity for the heterogeneous Fenton phenol degradation under natural or simulated sunlight irradiation with respect to analogous monometallic samples or than analogous FeCu NPs on graphite, activated carbon and P25 TiO2 semiconductor. FeCu/D3 catalyst exhibits good recyclability and stability especially working at pH 6. Overall, the high activity of the Fe20Cu80(0.2 wt%)/D3 catalyst is mainly due to the combination of the high activity of reduced copper species decomposing H2O2 to HO center dot radical, while Fe2+ allows the regeneration of these reduced copper species.S.N. thanks financial support by the Fundacion Ramon Areces (XVIII Concurso Nacional para la Adjudicacion de Ayudas a la Investigacion en Ciencias de la Vida y de la Materia, 2016), Ministerio de Ciencia, Innovacion y Universidades RTI2018-099482-A-I00 project and Generalitat Valenciana grupos de investigacion consolidables 2019 (ref: AICO/2019/214) project. H.G. thanks financial support by the Spanish Ministry of Science and Innovation (Severo Ochoa SEV2016 and RTI2018-890237-CO2-1) and Generalitat Valenciana (Prometeo 2017/083) is also gratefully acknowledged.Manickam-Periyaraman, P.; Espinosa, JC.; Ferrer Ribera, RB.; Subramanian, S.; Alvaro Rodríguez, MM.; García Gómez, H.; Navalón Oltra, S. (2020). Bimetallic iron-copper oxide nanoparticles supported on nanometric diamond as efficient and stable sunlight-assisted Fenton photocatalyst. Chemical Engineering Journal. 393:1-11. https://doi.org/10.1016/j.cej.2020.124770S111393Malato, S., Fernández-Ibáñez, P., Maldonado, M. I., Blanco, J., & Gernjak, W. (2009). Decontamination and disinfection of water by solar photocatalysis: Recent overview and trends. Catalysis Today, 147(1), 1-59. doi:10.1016/j.cattod.2009.06.018Pera-Titus, M., Garcı́a-Molina, V., Baños, M. A., Giménez, J., & Esplugas, S. (2004). Degradation of chlorophenols by means of advanced oxidation processes: a general review. Applied Catalysis B: Environmental, 47(4), 219-256. doi:10.1016/j.apcatb.2003.09.010Pignatello, J. J., Oliveros, E., & MacKay, A. (2006). Advanced Oxidation Processes for Organic Contaminant Destruction Based on the Fenton Reaction and Related Chemistry. Critical Reviews in Environmental Science and Technology, 36(1), 1-84. doi:10.1080/10643380500326564Rahim Pouran, S., Abdul Aziz, A. R., & Wan Daud, W. M. A. (2015). Review on the main advances in photo-Fenton oxidation system for recalcitrant wastewaters. Journal of Industrial and Engineering Chemistry, 21, 53-69. doi:10.1016/j.jiec.2014.05.005Cheng, M., Zeng, G., Huang, D., Lai, C., Xu, P., Zhang, C., & Liu, Y. (2016). Hydroxyl radicals based advanced oxidation processes (AOPs) for remediation of soils contaminated with organic compounds: A review. Chemical Engineering Journal, 284, 582-598. doi:10.1016/j.cej.2015.09.001Garrido-Ramírez, E. G., Theng, B. K. ., & Mora, M. L. (2010). Clays and oxide minerals as catalysts and nanocatalysts in Fenton-like reactions — A review. Applied Clay Science, 47(3-4), 182-192. doi:10.1016/j.clay.2009.11.044Klavarioti, M., Mantzavinos, D., & Kassinos, D. (2009). Removal of residual pharmaceuticals from aqueous systems by advanced oxidation processes. Environment International, 35(2), 402-417. doi:10.1016/j.envint.2008.07.009Bokare, A. D., & Choi, W. (2014). Review of iron-free Fenton-like systems for activating H2O2 in advanced oxidation processes. Journal of Hazardous Materials, 275, 121-135. doi:10.1016/j.jhazmat.2014.04.054Chiron, S. (2000). Pesticide chemical oxidation: state-of-the-art. Water Research, 34(2), 366-377. doi:10.1016/s0043-1354(99)00173-6Chong, M. N., Jin, B., Chow, C. W. K., & Saint, C. (2010). Recent developments in photocatalytic water treatment technology: A review. Water Research, 44(10), 2997-3027. doi:10.1016/j.watres.2010.02.039Herney-Ramirez, J., Vicente, M. A., & Madeira, L. M. (2010). Heterogeneous photo-Fenton oxidation with pillared clay-based catalysts for wastewater treatment: A review. Applied Catalysis B: Environmental, 98(1-2), 10-26. doi:10.1016/j.apcatb.2010.05.004Wang, C., Liu, H., & Sun, Z. (2012). Heterogeneous Photo-Fenton Reaction Catalyzed by Nanosized Iron Oxides for Water Treatment. International Journal of Photoenergy, 2012, 1-10. doi:10.1155/2012/801694Ramirez, J. H., Maldonado-Hódar, F. J., Pérez-Cadenas, A. F., Moreno-Castilla, C., Costa, C. A., & Madeira, L. M. (2007). Azo-dye Orange II degradation by heterogeneous Fenton-like reaction using carbon-Fe catalysts. Applied Catalysis B: Environmental, 75(3-4), 312-323. doi:10.1016/j.apcatb.2007.05.003Navalon, S., Sempere, D., Alvaro, M., & Garcia, H. (2013). Influence of Hydrogen Annealing on the Photocatalytic Activity of Diamond-Supported Gold Catalysts. ACS Applied Materials & Interfaces, 5(15), 7160-7169. doi:10.1021/am401489nEspinosa, J. C., Navalón, S., Álvaro, M., & García, H. (2015). Silver Nanoparticles Supported on Diamond Nanoparticles as a Highly Efficient Photocatalyst for the Fenton Reaction under Natural Sunlight Irradiation. ChemCatChem, 7(17), 2682-2688. doi:10.1002/cctc.201500458Espinosa, J. C., Navalón, S., Álvaro, M., & García, H. (2016). Copper nanoparticles supported on diamond nanoparticles as a cost-effective and efficient catalyst for natural sunlight assisted Fenton reaction. Catalysis Science & Technology, 6(19), 7077-7085. doi:10.1039/c6cy00572aEspinosa, J. C., Catalá, C., Navalón, S., Ferrer, B., Álvaro, M., & García, H. (2018). Iron oxide nanoparticles supported on diamond nanoparticles as efficient and stable catalyst for the visible light assisted Fenton reaction. Applied Catalysis B: Environmental, 226, 242-251. doi:10.1016/j.apcatb.2017.12.060Garrido-Ramírez, E. G., Marco, J. F., Escalona, N., & Ureta-Zañartu, M. S. (2016). Preparation and characterization of bimetallic Fe–Cu allophane nanoclays and their activity in the phenol oxidation by heterogeneous electro-Fenton reaction. Microporous and Mesoporous Materials, 225, 303-311. doi:10.1016/j.micromeso.2016.01.013Karthikeyan, S., Pachamuthu, M. P., Isaacs, M. A., Kumar, S., Lee, A. F., & Sekaran, G. (2016). Cu and Fe oxides dispersed on SBA-15: A Fenton type bimetallic catalyst for N,N -diethyl- p -phenyl diamine degradation. Applied Catalysis B: Environmental, 199, 323-330. doi:10.1016/j.apcatb.2016.06.040Martin, R., Navalon, S., Delgado, J. J., Calvino, J. J., Alvaro, M., & Garcia, H. (2011). Influence of the Preparation Procedure on the Catalytic Activity of Gold Supported on Diamond Nanoparticles for Phenol Peroxidation. Chemistry - A European Journal, 17(34), 9494-9502. doi:10.1002/chem.201100955Council Directive 98/83/EC of 3 November 1998 on the quality of water intended for human consumption.Dhakshinamoorthy, A., Navalon, S., Alvaro, M., & Garcia, H. (2012). Metal Nanoparticles as Heterogeneous Fenton Catalysts. ChemSusChem, 5(1), 46-64. doi:10.1002/cssc.201100517Burkitt, M. J., & Mason, R. P. (1991). Direct evidence for in vivo hydroxyl-radical generation in experimental iron overload: an ESR spin-trapping investigation. Proceedings of the National Academy of Sciences, 88(19), 8440-8444. doi:10.1073/pnas.88.19.8440Li, K., Zhao, Y., Janik, M. J., Song, C., & Guo, X. (2017). Facile preparation of magnetic mesoporous Fe3O4/C/Cu composites as high performance Fenton-like catalysts. Applied Surface Science, 396, 1383-1392. doi:10.1016/j.apsusc.2016.11.17

Photoactive Zr and Ti Metal-Organic-Frameworks for SolidState Solar Cells

This is the peer reviewed version of the following article: A. Melillo, R. García-Aboal, S. Navalón, P. Atienzar, B. Ferrer, M. Álvaro, H. García, ChemPhysChem 2021, 22, 842. ], which has been published in final form at https://doi.org/10.1002/cphc.202100083. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.[EN] Solid-state photovoltaic cells based on robust metal-organic frameworks (MOFs), MIL-125(Ti), MIL-125(Ti)-NH2, UiO-67, Ru(bpy)(2)-UiO-67, (bpy 2,2'-bipyridine) as active components and spiro-MeOTAD (MeOTAD 2,2',7,7'-tetrakis[N,N-di(p-methoxyphenyl)amino]-9,9 '-spirobifluorene) as hole transporting layer have been prepared., The photovoltaic response of this material increases in the presence of bathochromic -NH2 groups on the linker or Ru (II) polypyridyl complexes light harvester. These results show that the strategies typically employed in photocatalysis to enhance the photocatalytic activity of MOFs can also be applied in the field of photovoltaic devices.Financial support by the Spanish Ministry of Science and Innovation (Severo Ochoa and RTI2018-98276-CO2-1) and Generalitat Valenciana (Prometeo 2017/083) is gratefully acknowledged. S.N. thanks financial support by the Ministerio de Ciencia, Innovacion y Universidades (RTI 2018-099482-A-I00 project) and Agencia Valenciana de la Innovacion (AVI-GVA, Carboagua project, INNEST/2020/111).Melillo, A.; García-Aboal, R.; Navalón Oltra, S.; Atienzar Corvillo, PE.; Ferrer Ribera, RB.; Alvaro Rodríguez, MM.; García Gómez, H. (2021). Photoactive Zr and Ti Metal-Organic-Frameworks for SolidState Solar Cells. ChemPhysChem (Online). 22(9):842-848. https://doi.org/10.1002/cphc.202100083S84284822

Ruthenium(II) Tris(2,2'-bipyridyl) Complex Incorporated in UiO-67 as Photoredox Catalyst

This document is the Accepted Manuscript version of a Published Work that appeared in final form in The Journal of Physical Chemistry C, © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see http://doi.org/10.1021/acs.jpcc.8b07204[EN] Ruthenium(II) bis(2,2'-bipyridine) (2,2'-bipyridyl-5,5'-dicarboxylic acid), Rudcbpy, attached to the UiO-67(Zr) metal organic framework (MOF), generates upon visible light excitation the localized triplet excited state of the ruthenium(II) bipyridyl complex that decays partly to a very long-lived (millisecond time scale) photoinduced charge-separated state following a similar behavior as that of analogous ruthenium(II) tris(bipyridyl) complex dissolved in water, except that the lifetime of the soluble complex excited state is orders of magnitude shorter. The occurrence of photoinduced charge separation on the Rudcbpy-UiO-67(Zr) MOF has been proven visually by using methyl viologen as electron acceptor. Rudcbpy-UiO-67(Zr) behaves as a heterogeneous, reusable, photoredox catalyst promoting debromination of alpha-bromoketones with excellent selectivity at high conversions. Characterization data show that Rudcbpy-UiO-67(Zr) is stable under the photocatalytic reaction conditions.Financial support by the Spanish Ministry of Economy and Competitiveness (CTQ2014-53292-R-AR, Severo Ochoa, CTQ2015-69153-CO2-R) and Generalitat Valenciana (Prometeo 2017/083) is gratefully acknowledged. S.N. thanks the financial support by Fundacion Ramon Areces (XVIII Concurso Nacional, Ciencias de la Vida y de la Materia, Energia renovable: materiales y procesos 2016).Santiago-Portillo, A.; Garcia-Baldovi, H.; Carbonell Llopis, EJ.; Navalón Oltra, S.; Alvaro Rodríguez, MM.; García Gómez, H.; Ferrer Ribera, RB. (2018). Ruthenium(II) Tris(2,2'-bipyridyl) Complex Incorporated in UiO-67 as Photoredox Catalyst. The Journal of Physical Chemistry C. 122(51):29190-29199. https://doi.org/10.1021/acs.jpcc.8b07204S29190291991225

Ti as Mediator in the Photoinduced Electron Transfer of Mixed-Metal NH2-UiO-66(Zr/Ti): Transient Absorption Spectroscopy Study and Application in Photovoltaic Cell

This document is the Accepted Manuscript version of a Published Work that appeared in final form in The Journal of Physical Chemistry C, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see http://doi.org/10.1021/acs.jpcc.6b13068[EN] A series of mixed-metal NH2-UiO-66(Zr/Ti) with different percentages of exchanged Ti have been prepared and studied by transient absorption spectroscopy (TAS). The photogenerated transients from mixed NH2-UiO-66(Zr/Ti) exhibit at short time scales two defined absorption bands, evolving to a continuous absorption band expanding from 300 to 700 nm at longer time scales. The observed spectral changes are compatible with an initial formation of Ti3+-O-Zr4+ and its further transformation to Ti4+-O-Zr3+ via metal-metal electron exchange, thus providing support to the role of substituted Ti as mediator to facilitate electron transfer from excited ligand to the (Zr/Ti)(6)O-4(OH)(4) nodes in mixed NH2-UiO-66(Zr/Ti). The slow recombination of photogenerated electrons and holes in the mixed NH2-UiO-66(Zr/Ti) has been advantageously used for the construction of a photovoltaic cell fabricated with the mixed NH2-UiO-66(Zr/Ti), reaching a higher photon-to-current efficiency than NH2-UiO-66(Zr).Financial support by the Spanish Ministry of Economy and Competitiveness (CTQ2014-53292-R-AR, Severo Ochoa, CTQ2015-69153-CO2-R) is gratefully acknowledged. S.N. is thankful for financial support by Fundacion Ramon Areces (XVIII Concurso Nacional, Ciencias de la Vida y de la Materia, Energia renovable: materiales y procesos 2016).Financial support by the Spanish Ministry of Economy and Competitiveness (CTQ2014-53292-R-AR, Severo Ochoa, CTQ2015-69153-CO2-R) is gratefully acknowledged. S.N. is thankful for financial support by Fundacion Ramon Areces (XVIII Concurso Nacional, Ciencias de la Vida y de la Materia, Energia renovable: materiales y procesos 2016).cSantiago-Portillo, A.; Garcia-Baldovi, H.; García Fernández, MT.; Navalón Oltra, S.; Atienzar Corvillo, PE.; Ferrer Ribera, RB.; Alvaro Rodríguez, MM.... (2017). Ti as Mediator in the Photoinduced Electron Transfer of Mixed-Metal NH2-UiO-66(Zr/Ti): Transient Absorption Spectroscopy Study and Application in Photovoltaic Cell. The Journal of Physical Chemistry C. 121(12):7015-7024. https://doi.org/10.1021/acs.jpcc.6b13068S701570241211

Local deformation in a hydrogel induced by an external magnetic field

The aim of this study is to prove the feasibility of a system able to apply local mechanical loading on cells seeded in a hydrogel for tissue engineering applications. This experimental study is based on a previously developed artificial cartilage model with different concentrations of poly(vinyl alcohol) (PVA) that simulates the cartilage extracellular matrix (ECM). Poly(l-lactic acid) (PLLA) microspheres with dispersed magnetic nanoparticles (MNPs) were produced with an emulsion method. These microspheres were embedded in aqueous PVA solutions with varying concentration to resemble increased viscosity of growing tissue during regeneration. The ability to induce a local deformation in the ECM was assessed by applying a steady or an oscillatory magnetic field gradient to different PVA solutions containing the magnetic microparticles, similarly as in ferrogels. PLLA microparticle motion was recorded, and the images were analyzed. Besides, PVA gels and PLLA microparticles were introduced into the pores of a polycaprolactone scaffold, and the microparticle distribution and the mechanical properties of the construct were evaluated. The results of this experimental model show that the dispersion of PLLA microparticles containing MNPs, together with cells in a supporting gel, will allow applying local mechanical stimuli to cells during tissue regeneration. This local stimulation can have a positive effect on the differentiation of seeded cells and improve tissue regeneration.The authors gratefully acknowledge the financial support from the Spanish Ministry of Economy and Competitiveness through the MAT2013-46467-C4-1-R project, including the Feder funds. CIBER-BBN is an initiative funded by the VI National R&D&I Plan 2008-2011, Iniciativa Ingenio 2010, Consolider Program. CIBER Actions are financed by the Instituto de Salud Carlos III with assistance from the European Regional Development Fund. The authors thank "Servicio de Microscopia Electronica" of Universitat Politecnica de Valencia for their invaluable help. The translation of this paper was funded by the Universitat Politecnica de Valencia, Spain.Vikingsson, L.; Vinals Guitart, Á.; Valera Martínez, A.; Riera Guasp, J.; Vidaurre Garayo, AJ.; Gallego Ferrer, G.; Gómez Ribelles, JL. (2016). Local deformation in a hydrogel induced by an external magnetic field. Journal of Materials Science. 51(22):9979-9990. https://doi.org/10.1007/s10853-016-0226-8S997999905122Eyre D (2002) Collagen of articular cartilage. Arthritis Res 4:30–35Roughley PJ, Lee ER (1994) Cartilage proteoglycans: structure and potential functions. Microsc Res Tech 28:385–397Gillard GC, Reilly HC, Bell-Booth PG, Flint MH (1979) The influence of mechanical forces on the glycosaminoglycan content of the rabbit flexor digitorum profundus tendon. 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