Laurent, S.; Henoumont, C.; Stanicki, D.; Boutry, S.; Lipani, E.; Belaid, S.; Muller, R.N.; Vander Elst, L. MRI Contrast Agents: From Molecules to Particles; SpringerBriefs in Applied Sciences and Technology; Springer: Singapore, 2017.
Wahsner, J.; Gale, E.M.; Rodríguez-Rodríguez, A.; Caravan, P. Chemistry of MRI Contrast Agents: Current Challenges and New Frontiers. Chem. Rev. 2019, 119, 957–1057. [CrossRef] [PubMed]
Ni, D.; Bu, W.; Ehlerding, E.B.; Cai, W.; Shi, J. Engineering of inorganic nanoparticles as magnetic resonance imaging contrast agents. Chem. Soc. Rev. 2017, 46, 7438–7468. [CrossRef] [PubMed]
Shen, Z.; Wu, A.; Chen, X. Iron Oxide Nanoparticle Based Contrast Agents for Magnetic Resonance Imaging. Mol. Pharm. 2017, 14, 1352–1364. [CrossRef] [PubMed]
Vallabani, N.V.S.; Singh, S. Recent advances and future prospects of iron oxide nanoparticles in biomedicine and diagnostics. 3 Biotech 2018, 8, 279. [CrossRef] [PubMed]
Suárez-García, S.; Arias-Ramos, N.; Frias, C.; Candiota, A.P.; Arús, C.; Lorenzo, J.; Ruiz-Molina, D.; Novio, F. Dual T1/T2 Nanoscale Coordination Polymers as Novel Contrast Agents for MRI: A Preclinical Study for Brain Tumor. ACS Appl. Mater. Interfaces 2018, 10, 38819–38832. [CrossRef] [PubMed]
Jafari, A.; Salouti, M.; Shayesteh, S.F.; Heidari, Z.; Rajabi, A.B.; Boustani, K.; Nahardani, A. Synthesis and characterization of Bombesin-superparamagnetic iron oxide nanoparticles as a targeted contrast agent for imaging of breast cancer using MRI. Nanotechnology 2015, 26, 075101. [CrossRef]
Hayashi, K.; Nakamura, M.; Sakamoto, W.; Yogo, T.; Miki, H.; Ozaki, S.; Abe, M.; Matsumoto, T.; Ishimura, K. Superparamagnetic Nanoparticle Clusters for Cancer Theranostics Combining Magnetic Resonance Imaging and Hyperthermia Treatment. Theranostics 2013, 3, 366–376. [CrossRef]
Wu, M.; Zhang, D.; Zeng, Y.; Wu, L.; Liu, X.; Liu, J. Nanocluster of superparamagnetic iron oxide nanoparticles coated with poly (dopamine) for magnetic field-targeting, highly sensitive MRI and photothermal cancer therapy. Nanotechnology 2015, 26, 115102. [CrossRef]
Revia, R.A.; Zhang, M. Magnetite nanoparticles for cancer diagnosis, treatment, and treatment monitoring: Recent advances. Mater. Today 2016, 19, 157–168. [CrossRef]
Glaria, A.; Soulé, S.; Hallali, N.; Ojo, W.S.; Mirjolet, M.; Fuks, G.; Cornejo, A.; Allouche, J.; Dupin, J.C.; Martinez, H.; et al. Silica coated iron nanoparticles: Synthesis, interface control, magnetic and hyperthermia properties. 2018, 8, 32146–32156. [CrossRef]
Wang, C.M.; Baer, D.R.; Thomas, L.E.; Amonette, J.E.; Antony, J.; Qiang, Y.; Duscher, G. Void formation during early stages of passivation: Initial oxidation of iron nanoparticles at room temperature. J. Appl. Phys. 2005, 98, 094308. [CrossRef]
Miguel, O.B.; Gossuin, Y.; Morales, M.P.; Gillis, P.; Muller, R.N.; Veintemillas-Verdaguer, S. Comparative analysis of the 1H NMR relaxation enhancement produced by iron oxide and core-shell iron–iron oxide nanoparticles. Magn. Reson. Imaging 2007, 25, 1437–1441. [CrossRef] [PubMed]
Cheong, S.; Ferguson, P.; Feindel, K.W.; Hermans, I.F.; Callaghan, P.T.; Meyer, C.; Slocombe, A.; Su, C.-H.; Cheng, F.-Y.; Yeh, C.-S.; et al. Simple Synthesis and Functionalization of Iron Nanoparticles for Magnetic Resonance Imaging. Angew. Chem. Int. Ed. 2011, 50, 4206–4209. [CrossRef] [PubMed]
Lacroix, L.-M.; Frey Huls, N.; Ho, D.; Sun, X.; Cheng, K.; Sun, S. Stable Single-Crystalline Body Centered Cubic Fe Nanoparticles. Nano Lett. 2011, 11, 1641–1645. [CrossRef]
Hadjipanayis, C.G.; Bonder, M.J.; Balakrishnan, S.; Wang, X.; Mao, H.; Hadjipanayis, G.C. Metallic Iron Nanoparticles for MRI Contrast Enhancement and Local Hyperthermia. Small 2008, 4, 1925–1929. [CrossRef]
Ferguson, P.M.; Feindel, K.W.; Slocombe, A.; MacKay, M.; Wignall, T.; Delahunt, B.; Tilley, R.D.; Hermans, I.F. Strongly Magnetic Iron Nanoparticles Improve the Diagnosis of Small Tumours in the Reticuloendothelial System by Magnetic Resonance Imaging. PLoS ONE 2013, 8, e56572. [CrossRef]
Yoon, T.-J.; Lee, H.; Shao, H.; Weissleder, R. Highly Magnetic Core-Shell Nanoparticles with a Unique Magnetization Mechanism. Angew. Chem. Int. Ed. 2011, 50, 4663–4666. [CrossRef]
Zhou, Z.; Sun, Y.; Shen, J.; Wei, J.; Yu, C.; Kong, B.; Liu, W.; Yang, H.; Yang, S.; Wang, W. Iron/iron oxide core/shell nanoparticles for magnetic targeting MRI and near-infrared photothermal therapy. Biomaterials 2014, 35, 7470–7478. [CrossRef]
Masoudi, A.; Madaah Hosseini, H.R.; Seyed Reyhani, S.M.; Shokrgozar, M.A.; Oghabian, M.A.; Ahmadi, R. Long-term investigation on the phase stability, magnetic behavior, toxicity, and MRI characteristics of superparamagnetic Fe/Fe-oxide core/shell nanoparticles. Int. J. Pharm. 2012, 439, 28–40. [CrossRef]
Dumestre, F.; Chaudret, B.; Amiens, C.; Renaud, P.; Fejes, P. Superlattices of Iron Nanocubes Synthesized from Fe[N(SiMe3)2]2. Science 2004, 303, 821–823. [CrossRef]
Margeat, O.; Respaud, M.; Amiens, C.; Lecante, P.; Chaudret, B. Ultrafine metallic Fe nanoparticles: Synthesis, structure and magnetism. Beilstein J. Nanotechnol. 2010, 1, 108–118. [CrossRef] [PubMed]
Lacroix, L.-M.; Lachaize, S.; Falqui, A.; Blon, T.; Carrey, J.; Respaud, M.; Dumestre, F.; Amiens, C.; Margeat, O.; Chaudret, B.; et al. Ultrasmall iron nanoparticles: Effect of size reduction on anisotropy and magnetization. J. Appl. Phys. 2008, 103, 07D521. [CrossRef]
Lacroix, L.-M.; Lachaize, S.; Falqui, A.; Respaud, M.; Chaudret, B. Iron Nanoparticle Growth in Organic Superstructures. J. Am. Chem. Soc. 2009, 131, 549–557. [CrossRef] [PubMed]
Margeat, O.; Dumestre, F.; Amiens, C.; Chaudret, B.; Lecante, P.; Respaud, M. Synthesis of iron nanoparticles: Size effects, shape control and organisation. Prog. Solid State Chem. 2005, 33, 71–79. [CrossRef]
Meffre, A.; Lachaize, S.; Gatel, C.; Respaud, M.; Chaudret, B. Use of long chain amine as a reducing agent for the synthesis of high quality monodisperse iron(0) nanoparticles. J. Mater. Chem. 2011, 21, 13464–13469. [CrossRef]
Caltagirone, C.; Bettoschi, A.; Garau, A.; Montis, R. Silica-based nanoparticles: A versatile tool for the development of efficient imaging agents. Chem. Soc. Rev. 2015, 44, 4645–4671. [CrossRef]
Chen, F.; Hableel, G.; Zhao, E.R.; Jokerst, J.V. Multifunctional nanomedicine with silica: Role of silica in nanoparticles for theranostic, imaging, and drug monitoring. J. Colloid Interface Sci. 2018, 521, 261–279. [CrossRef]
Ding, H.L.; Zhang, Y.X.; Wang, S.; Xu, J.M.; Xu, S.C.; Li, G.H. Fe3O4@SiO2 Core/Shell Nanoparticles: The Silica Coating Regulations with a Single Core for Different Core Sizes and Shell Thicknesses. Chem. Mater. 2012, 24, 4572–4580. [CrossRef]
Chen, F.; Bu, W.; Chen, Y.; Fan, Y.; He, Q.; Zhu, M.; Liu, X.; Zhou, L.; Zhang, S.; Peng, W.; et al. A Sub-50-nm Monosized Superparamagnetic Fe3O4@SiO2 T2-Weighted MRI Contrast Agent: Highly Reproducible Synthesis of Uniform Single-Loaded Core-Shell Nanostructures. Chem. Asian J. 2009, 4, 1809–1816. [CrossRef]
Glorani, G.; Marin, R.; Canton, P.; Pinto, M.; Conti, G.; Fracasso, G.; Riello, P. Pegylated silica nanoparticles: Cytotoxicity and macrophage uptake. J. Nanoparticle Res. 2017, 19, 294. [CrossRef]
Herman, D.A.J.; Ferguson, P.; Cheong, S.; Hermans, I.F.; Ruck, B.J.; Allan, K.M.; Prabakar, S.; Spencer, J.L.; Lendrum, C.D.; Tilley Richard, D. Hot-injection synthesis of iron/iron oxide core/shell nanoparticles for T2 contrast enhancement in magnetic resonance imaging. Chem. Commun. 2011, 47, 9221. [CrossRef] [PubMed]
Schumaker, N.E.; Garland, C.W. Infrared Investigation of Structural and Ordering Changes in Ammonium Chloride and Bromide. J. Chem. Phys. 1970, 53, 392–407. [CrossRef]
Fredrickson, L.R.; Decius, J.C. The Raman spectrum of the ordered phase of NH4Cl and ND4Cl: Dipole and polarizability derivatives. J. Chem. Phys. 1977, 66, 2297–2305. [CrossRef]
Gharbi, K. Elaboration de Nanoparticules d’or et de fer pour des Applications Biomédicales. Ph.D. Thesis, Université Toulouse III Paul Sabatier, Toulouse, France, 2017.
Accordingly, the IR spectrum of the dried ethanol supernatant showed the presence of NH4Cl (3114 cm−1, 3003 cm−1, 2816 cm−1, 1390 cm−1), and aliphatic chains (2916 cm−1 and 2849 cm−1) attributed to residual HAD·HCl (Figure SI 3b).
Trunova, A.V.; Meckenstock, R.; Barsukov, I.; Hassel, C.; Margeat, O.; Spasova, M.; Lindner, J.; Farle, M. Magnetic characterization of iron nanocubes. J. Appl. Phys. 2008, 104, 093904. [CrossRef]
Branca, M.; Marciello, M.; Ciuculescu-Pradines, D.; Respaud, M.; Morales, M.D.P.; Serra, R.; Casanove, M.-J.; Amiens, C. Towards MRI T2 contrast agents of increased efficiency. J. Magn. Magn. Mater. 2015, 377, 348–353. [CrossRef]
Toney, M.; Davenport, A.; Oblonsky, L.; Ryan, M.; Vitus, C. Atomic Structure of the Passive Oxide Film Formed on Iron. Phys. Rev. Lett. 1997, 79, 4282–4285. [CrossRef]
Wang, C.; Baer, D.R.; Amonette, J.E.; Engelhard, M.H.; Antony, J.; Qiang, Y. Morphology and Electronic Structure of the Oxide Shell on the Surface of Iron Nanoparticles. J. Am. Chem. Soc. 2009, 131, 8824–8832. [CrossRef]
Signorini, L.; Pasquini, L.; Savini, L.; Carboni, R.; Boscherini, F.; Bonetti, E.; Giglia, A.; Pedio, M.; Mahne, N.; Nannarone, S. Size-dependent oxidation in iron/iron oxide core-shell nanoparticles. Phys. Rev. B 2003, 68. [CrossRef]
Liz-Marzán, L.M.; Giersig, M.; Mulvaney, P. Synthesis of Nanosized Gold−Silica Core−Shell Particles. Langmuir 1996, 12, 4329–4335. [CrossRef]
EDX study confirmed the silica shell / iron rich core architecture (Figure S6). We assume that TEOS is not fully condensed at this stage, based on 29Si MAS NMR studies carried out on NPSiO2 taken as a reference (see supplementary information for details).
Joshi, H.M.; De, M.; Richter, F.; He, J.; Prasad, P.V.; Dravid, V.P. Effect of silica shell thickness of Fe3O4 –SiOx core–shell nanostructures on MRI contrast. J. Nanoparticle Res. 2013, 15, 1448. [CrossRef]
Perry, J.L.; Reuter, K.G.; Kai, M.P.; Herlihy, K.P.; Jones, S.W.; Luft, J.C.; Napier, M.; Bear, J.E.; DeSimone, J.M. PEGylated PRINT Nanoparticles: The Impact of PEG Density on Protein Binding, Macrophage Association, Biodistribution, and Pharmacokinetics. Nano Lett. 2012, 12, 5304–5310. [CrossRef]
Lee, N.; Hyeon, T. Designed synthesis of uniformly sized iron oxide nanoparticles for efficient magnetic resonance imaging contrast agents. Chem. Soc. Rev. 2012, 41, 2575–2589. [CrossRef]
Koenig, S.H.; Kellar, K.E. Theory of 1/T1 and 1/T2 NMRD profiles of solutions of magnetic nanoparticles. Magn. Reson. Med. 1995, 34, 227–233. [CrossRef] [PubMed]
Pinho, S.L.C.; Laurent, S.; Rocha, J.; Roch, A.; Delville, M.-H.; Mornet, S.; Carlos, L.D.; Vander Elst, L.; Muller, R.N.; Geraldes, C.F.G.C. Relaxometric Studies of γ-Fe2O3@SiO2 Core Shell Nanoparticles: When the Coating Matters. J. Phys. Chem. C 2012, 116, 2285–2291. [CrossRef]
Harisinghani, M.G.; Barentsz, J.; Hahn, P.F.; Deserno, W.M.; Tabatabaei, S.; van de Kaa, C.H.; de la Rosette, J.; Weissleder, R. Noninvasive Detection of Clinically Occult Lymph-Node Metastases in Prostate Cancer. N. Engl. J. Med. 2003, 348, 2491–2499. [CrossRef]
McGrath, A.J.; Dolan, C.; Cheong, S.; Herman, D.A.J.; Naysmith, B.; Zong, F.; Galvosas, P.; Farrand, K.J.; Hermans, I.F.; Brimble, M.; et al. Stability of polyelectrolyte-coated iron nanoparticles for T2-weighted magnetic resonance imaging. J. Magn. Magn. Mater. 2017, 439, 251–258. [CrossRef]
He, Q.; Zhang, J.; Shi, J.; Zhu, Z.; Zhang, L.; Bu, W.; Guo, L.; Chen, Y. The effect of PEGylation of mesoporous silica nanoparticles on nonspecific binding of serum proteins and cellular responses. Biomaterials 2010, 31, 1085–1092. [CrossRef]
Roch, A.; Muller, R.N.; Gillis, P. Theory of proton relaxation induced by superparamagnetic particles. J. Chem. Phys. 1999, 110, 5403–5411. [CrossRef]
Laurent, S.; Forge, D.; Port, M.; Roch, A.; Robic, C.; Vander Elst, L.; Muller, R.N. Magnetic Iron Oxide Nanoparticles: Synthesis, Stabilization, Vectorization, Physicochemical Characterizations, and Biological Applications. Chem. Rev. 2008, 108, 2064–2110. [CrossRef] [PubMed]
Xu, M.; McCanna, D.J.; Sivak, J.G. Use of the viability reagent PrestoBlue in comparison with alamarBlue and MTT to assess the viability of human corneal epithelial cells. J. Pharmacol. Toxicol. Methods 2015, 71, 1–7. [CrossRef] [PubMed]
Li, Y.-F.; Chen, C. Fate and Toxicity of Metallic and Metal-Containing Nanoparticles for Biomedical Applications. Small 2011, 7, 2965–2980. [CrossRef] [PubMed]