PHENIX directory

PHENIX directory

Jérôme Fresnais

CR, chargé de recherche

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My works deal with the conception and study of of multi-scale nano-structured magnetic materials.
For few years now, we have investigated controlled pathway to assemble nanoparticles with oppositely charged polyelectrolytes. We used those systems to evaluate the heating properties of iron oxide in the aggregated state.
We have also deeply considered the control of magnetic anisotropy of iron oxide nanoparticles through a surface functionalization with molecular complexes.
We recently explored the temperature gradient around iron oxide nanoparticles to induce locale effects without macroscopic temperature increases.
At last, we have recently examined the wetting of micro-structured magnetic elastomer surfaces. The influence of the deflection of magnetic pillars on the displacement of a droplet on a tilted surface was elucidated, as well as the role of Young modulus on the wetting contact angle. Those materials could be of interest toward microfluidic platforms.


Electrostatic interactions

My work deals with the dispersion of magnetic nanoparticles in complex media such as brine solutions, ionic liquid, and polymer melts.
I also investigate the control of interactions between magnetic nanoparticles and oppositely charged polyelectrolytes (hydrophilic to amphihilic ones) to prepare magnetic aggregates with controlled size and morphology. They are used as microrheological or hyperthermia probes.

electrostatic assembly
TEM image of a fluorescent magnetic rod

My research currently focuses on the effect of aggregation of magnetic nanoparticles on their hyperthermia efficiency. This study is conducted into different media (water, ionic liquid, and PDMS).

During the Ph D. of Clément Guibert, we have evidenced that aggregation lead to a decrease of hyperthermia efficiency. On the more, compactness of aggregates plays a central role on the hyperthermia efficiency : the more dense, the less effective (Guibert C. et al., J Phys Chem C, 2015, 119, 28148).

Magnetically tunable anisotropy 

Owing to their magnetic properties, iron oxide nanoparticles are of considerable interest for applications in high-density data storage or in medicine. In the case of small particles though, the superparamagnetic limit is reached and the relevant magnetic properties lost. Retaining appealing magnetic properties while maintaining a small nanoparticle size has thus proved a highly challenging task. However, in these small nanoparticles, the magnetic properties are predominantly governed by the surface magnetic anisotropy and modifying it represents one of the best approaches to improve the properties. Following this approach, we have been investigating a novel synthetic strategy to enhance the anisotropy of sub-10 nm maghemite nanoparticles. Surface functionalization was achieved to coordinate anisotropic cobalt containing complexes to the surface of maghemite nanoparticles (Y. Prado et al., Nature Comm 2015).

Strategy to functionalize iron oxide nanoparticles with molecular complexes

To further our comprehension of the surface anisotropy effect, we have investigated different particles sizes and different complexes (either changing the metal nature (Co, Ni) or the complex geometry). Thus, three batches of nanoparticles with diameters of 4.2 nm, 5.9 nm, and 8.5 nm with low polydispersity were synthesized (figure 1a). Additionally, several complexes were successfully prepared, allowing one or two available coordination sites toward the nanoparticles surface (figure 1b).

In the case of [CoII(TPMA)Cl2] complexes (TPMA : tris(2- pyridylmethyl)amine), a first evidence of the role of surface functionalization is given by the variation of hydrodynamic diameter versus the functionalization rate. When normalized to the diameter of particles, a domain with good colloidal stability is revealed for less than 1.8 complexes per nm2 (figure 2a). In this range of surface functionalization, a significant and progressive increase of the magnetic anisotropy (coercive fields measured at 5 K and blocking temperatures determined with zero-field-cooled and field-cooled curves) was obtained, and directly correlated to the amount of complexes at the surface of the nanoparticles (figure 2b). Besides, element-specific X-ray Absorption Spectroscopy (XAS) and X-ray Magnetic Circular Dichroism (XMCD) reveal the existence of a room-temperature persistent magnetic interaction between the complexes and the nanoparticles as the possible origin of the enhancement effect. Our strategy is thus unique to tune the enhancement of the anisotropy in iron oxide nanoparticles.

Magnetically activable superhydrophobic surfaces

During the Ph D. of Blandine Bolteau, supervised also by Etienne Barthel (SIMM) and Jeremie Teisseire (SVI – Saint Gobain), we have synthesized magnetic elastomer micro-pillar arrays with tunable Young moduli, aspect ratios, and surface densities.
We evidenced that Young Modulus has no influence on macroscopic contact angle (either advancing or receding contact angle).

Receding contact angle versus Young modulus of the elastomer

We are also able to tune the displacement of a water droplet on a tilted surface by controlling the movement of the pillars by the application of a periodic magnetic field (with a permanent magnet).

Droplet displacement versus time (grey areas corresponf to a mouvement of the magnet under the surface)

Other videos can be seen at the YouTube links below : : Deflexion of pilars under magnetic actuation (Sylgard 184 @ 14% by volume of particles). : Deflexion and interaction between pilars (Sylgard 184 @ 16% by volume of particles). : chaining of magentic pilars under magnetic actuation (Sylgard 184 @ 16% by volume of particles). : Displacement of the triple line under magnetic actuation (optical microscopy). : remote control of the sliding of a droplet on a tilted surface (Sylgard 184 @ 16% by volume of particles, tilting angle of 13°). : Controled displacement of a droplet on a tilted surface under periodic magnetic actuation (Sylgard 184 @ 16% by volume of particles, tilting angle of 11° with constant actuation frequency). : Controled displacement of a droplet on a tilted surface under periodic magnetic actuation (Sylgard 184 @ 16% by volume of particles, tilting angle of 11° with variable actuation frequency).


1. Fresnais, J. ; Benyahia, L. ; Chapel, J. P. ; Poncin-Epaillard, F. Polyethylene Ultrahydrophobic Surface : Synthesis and Original Properties. The European Physical Journal Applied Physics 2004, 26 (03), 209–214.

2. Fresnais, J. ; Benyahia, L. ; Poncin‐Epaillard, F. Dynamic (de) Wetting Properties of Superhydrophobic Plasma‐treated Polyethylene Surfaces. Surface and interface analysis 2006, 38 (3), 144–149.

3. Fresnais, J. ; Chapel, J. P. ; Poncin-Epaillard, F. Synthesis of Transparent Superhydrophobic Polyethylene Surfaces. Surface and Coatings Technology 2006, 200 (18), 5296–5305.

4. Qi, L. ; Chapel, J.-P. ; Castaing, J.-C. ; Fresnais, J. ; Berret, J.-F. Stability and Adsorption Properties of Electrostatic Complexes : Design of Hybrid Nanostructures for Coating Applications. Langmuir 2007, 23 (24), 11996–11998.

5. Fresnais, J. ; Berret, J. F. ; Frka-Petesic, B. ; Sandre, O. ; Perzynski, R. Electrostatic Co-Assembly of Iron Oxide Nanoparticles and Polymers : Towards the Generation of Highly Persistent Superparamagnetic Nanorods. Advanced Materials 2008, 20 (20), 3877–3881.

6. Fresnais, J. ; Berret, J. F. ; Qi, L. ; Chapel, J. P. ; Castaing, J. C. ; Sandre, O. ; Frka-Petesic, B. ; Perzynski, R. ; Oberdisse, J. ; Cousin, F. Universal Scattering Behavior of Coassembled Nanoparticle-Polymer Clusters. Physical Review E 2008, 78 (4), 040401.

7. Qi, L. ; Sehgal, A. ; Castaing, J.-C. ; Chapel, J.-P. ; Fresnais, J. ; Berret, J.-F. ; Cousin, F. Redispersible Hybrid Nanopowders : Cerium Oxide Nanoparticle Complexes with Phosphonated-PEG Oligomers. ACS Nano 2008, 2 (5), 879–888.

8. Qi, L. ; Chapel, J. P. ; Castaing, J. C. ; Fresnais, J. ; Berret, J. F. Organic versus hybrid coacervate complexes : co-assembly and adsorption properties, Soft Matter 2008, 4 (3), 577-585.

9. Fresnais, J. ; Berret, J. F. ; Frka-Petesic, B. ; Sandre, O. ; Perzynski R., Reorientation kinetics of superparamagnetic nanostructured rods, Journal of Physics : Condensed Matter 2008, 20 (49), 494216.

10. Chanteau, B. ; Fresnais, J. ; Berret, J. F. Electrosteric Enhanced Stability of Functional Sub-10 Nm Cerium and Iron Oxide Particles in Cell Culture Medium. Langmuir 2009, 25 (16), 9064–9070.

11. Fresnais, J. ; Ishow, E. ; Sandre, O. ; Berret, J. F. Electrostatic Co-assembly of Magnetic Nanoparticles and Fluorescent Nanospheres : A Versatile Approach Towards Bimodal Nanorods. Small 2009, 5 (22), 2533–2536.

12. Fresnais, J. ; Lavelle, C. ; Berret, J. F. Nanoparticle Aggregation Controlled by Desalting Kinetics, Journal of Physical Chemistry C 2009, 113 (37), 16371-16379.

13. Fresnais, J. ; Chapel, J. P. ; Benyahia, L. ; Poncin-Epaillard, F. Plasma-Treated Superhydrophobic Polyethylene Surfaces : Fabrication, Wetting and Dewetting Properties Journal of adhesion science and technology 2009, 23 (3), 447-467.

14. Frka-Petesic, B. ; Fresnais, J. ; Berret, J. F. ; Dupuis, V. ; Perzynski, R. ; Sandre, O. Stabilization and controlled association of superparamagnetic nanoparticles using block copolymers, Journal of Magnetism and Magnetic Materials 2009, 321 (7), 667-670.

15. Qi, L. ; Fresnais, J. ; Berret, J. F. ; Castaing, J. C. ; Grillo, I. ; Chapel, J. P. Influence of the Formulation Process in Electrostatic Assembly of Nanoparticles and Macromolecules in Aqueous Solution : The Mixing Pathway. The Journal of Physical Chemistry C 2010, 114 (30), 12870–12877.

16. Qi, L. ; Fresnais, J. ; Berret, J. F. ; Castaing, J. C. ; Destremaut, F. ; Salmon, J. B. ; Cousin, F. ; Chapel, J. P. Influence of the Formulation Process in Electrostatic Assembly of Nanoparticles and Macromolecules in Aqueous Solution : The Interaction Pathway. The Journal of Physical Chemistry C 2010, 114 (39), 16373-16381.

17. Yan, M. ; Fresnais, J. ; Berret, J. F. Growth Mechanism of Nanostructured Superparamagnetic Rods Obtained by Electrostatic Co-Assembly. Soft Matter 2010, 6 (9), 1997–2005.

18. Breton, M. ; Prével, G. ; Audibert, J. F. ; Pansu, R. ; Tauc, P. ; Le Pioufle, B. ; Français, O. ; Fresnais, J. ; Berret, J. F. ; Ishow, E. Solvatochromic Dissociation of Non-Covalent Fluorescent Organic Nanoparticles upon Cell Internalization. Physical Chemistry Chemical Physics 2011, 13 (29), 13268–13276.

19. Frka-Petesic, B. ; Erglis, K. ; Berret, J. F. ; Cebers, A. ; Dupuis, V. ; Fresnais, J. ; Sandre, O. ; Perzynski, R. Dynamics of Paramagnetic Nanostructured Rods under Rotating Field. Journal of Magnetism and Magnetic Materials 2011, 323 (10), 1309–1313.

20. Le Digabel, J. ; Biais, N. ; Fresnais, J. ; Berret, J. F. ; Hersen, P. ; Ladoux, B. Magnetic Micropillars as a Tool to Govern Substrate Deformations. Lab on a Chip 2011, 11 (15), 2630–2636.

21. Yan, M. ; Fresnais, J. ; Sekar, S. ; Chapel, J. P. ; Berret, J. F., Magnetic Nanowires Generated via the Waterborne Desalting Transition Pathway. Acs Applied Materials & Interfaces 2011, 3 (4), 1049-1054.

22. Iversen, N. K. ; Frische, S. ; Thomsen, K. ; Laustsen, C. ; Pedersen, M. ; Hansen, P. B. L. ; Bie, P. ; Fresnais, J. ; Berret, J. F. ; Baatrup, E. Superparamagnetic Iron Oxide Polyacrylic Acid Coated γ-Fe2O3 Nanoparticles Does Not Affect Kidney Function but Causes Acute Effect on the Cardiovascular Function in Healthy Mice. Toxicology and Applied Pharmacology 2012, 266 (2), 276-288.

23. Robbes, A. S. ; Cousin, F. ; Meneau, F. ; Chevigny, C. ; Gigmes, D. ; Fresnais, J. ; Schweins, R. ; Jestin, J. Controlled Grafted Brushes of Polystyrene on Magnetic γ-Fe2O3 Nanoparticles via Nitroxide-Mediated Polymerization. Soft Matter 2012, 8 (12), 3407–3418.

24. Sötebier, C. ; Michel, A. ; Fresnais, J. Polydimethylsiloxane (PDMS) Coating onto Magnetic Nanoparticles Induced by Attractive Electrostatic Interaction. Applied Sciences. 2012, pp 485–495.

25. Vuong, Q. L. ; Berret, J.-F. ; Fresnais, J. ; Gossuin, Y. ; Sandre, O. A Universal Scaling Law to Predict the Efficiency of Magnetic Nanoparticles as MRI T2-Contrast Agents. Advanced Healthcare Materials 2012, 1 (4), 502–512.

26. Qi, L. ; Fresnais, J. ; Muller, P. ; Theodoly, O. ; Berret, J. F. ; Chapel, J. P., Interfacial Activity of Phosphonated-PEG Functionalized Cerium Oxide Nanoparticles, Langmuir 2012, 28 (31), 11448-11456.

27. Fresnais, J. ; Yan, M. ; Courtois, J. ; Bostelmann, T. ; Bée, A. ; Berret, J.-F. Poly(acrylic Acid)-Coated Iron Oxide Nanoparticles : Quantitative Evaluation of the Coating Properties and Applications for the Removal of a Pollutant Dye. Journal of Colloid and Interface Science 2013, 395, 24–30.

28. N’Guyen, T. T. T. ; Duong, H. T. T. ; Basuki, J. ; Montembault, V. ; Pascual, S. ; Guibert, C. ; Fresnais, J. ; Boyer, C. ; Whittaker, M. R. ; Davis, T. P. ; et al. Functional Iron Oxide Magnetic Nanoparticles with Hyperthermia-Induced Drug Release Ability by Using a Combination of Orthogonal Click Reactions. Angewandte Chemie International Edition 2013, 52 (52), 14152–14156.

29. Faucon A., Fresnais J., Brosseau A., Hulin P., Nedellec S., Hemez J., Ishow E., Photoactive chelating organic nanospheres as central platforms of bimodal hybrid nanoparticles. Journal of Material Chemistry C 2013, 1, 3879-3886.

30. Vitorazi, L. ; Ould-Moussa, N. ; Sekar, S. ; Fresnais, J. ; Loh, W. ; Chapel, J.-P. ; Berret, J.-F. Evidence of a Two-Step Process and Pathway Dependency in the Thermodynamics of Poly(diallyldimethylammonium Chloride)/poly(sodium Acrylate) Complexation. Soft Matter 2014, 10 (47), 9496–9505.

31. Faucon, A. ; Maldiney, T. ; Clément, O. ; Hulin, P. ; Nedellec, S. ; Robard, M. ; Gautier, N. ; De Meulenaere, E. ; Clays, K. ; Orlando, T. ; et al. Highly Cohesive Dual Nanoassemblies for Complementary Multiscale Bioimaging. Journal of Material Chemistry B 2014, 2 (44), 7747–7755.

32. Guibert, C. ; Dupuis, V. ; Fresnais, J. ; Peyre, V. Controlling Nanoparticles Dispersion in Ionic Liquids by Tuning the pH. Journal of Colloid and Interface Science 2015, 454 (0), 105–111.

33. Griffete N., Fresnais J., Espinosa A., Wilhelm C., Bée A., Ménager C., Design of magnetic molecularly imprinted
polymer nanoparticles for controlled release of doxorubicin under an alternative magnetic field
in athermal conditions. Nanoscale 2015, 7, 18891-18896.

34. Prado Y., Daffé N., Michel A., Georgelin T., Yaacoub N., Grenèche JM, Choueikani F., Otero E., Ohresser P., Arrio MA., Cartier-dit-Moulin C., Sainctavit Ph., Fleury B., Dupuis V., Lisnard L., Fresnais J., Enhancing the magnetic anisotropy of maghemite nanoparticles via the surface coordination of molecular complexes. Nature Communications 2015, DOI : 10.1038/ncomms10139.

35. Guibert C., Dupuis V., Peyre V., Fresnais J., Hyperthermia of Magnetic Nanoparticles : Experimental Study of the Role of Aggregation, The Journal of Physical Chemistry C, 2015, 119 (50), 28148–28154.

36. Faucon, A., Benhelli-Mokrani, H., Fleury, F., Dubreil, L., Hulin, P., Nedellec, S., Doussineau, T., Antoine, R., Orlando, T., Lascialfari, A., Fresnais, J., Lartigue, L., Ishow, E., Tuning the architectural integrity of high-performance magneto-fluorescent core-shell nanoassemblies in cancer cells. Journal of Colloid and Interface Science 2016, 479, 139–149.
37. Caetano, B.L., Guibert, C., Fini, R., Fresnais, J., Pulcinelli, S.H., Menager, C., Santilli, C.V., Magnetic hyperthermia-induced drug release from ureasil-PEO-γ-Fe2O3 nanocomposites. RSC Adv. 2016, 6, 63291–63295

38. Guibert, C. ; Fresnais, J. ; Peyre, V. ; Dupuis, V. Magnetic Fluid Hyperthermia Probed by Both Calorimetric and Dynamic Hysteresis Measurements. J. Magn. Magn. Mater. 2017, 421, 384–392.

39. B. Rozic, J. Fresnais, C. Molinaro, J. Calixte, S. Umadevi, S. Lau-Truong, N. Felidj, T. Kraus, F. Charra, V. Dupuis, T. Hegmann, C. Fiorini-Debuisschert, B. Gallas, E. Lacaze. Oriented Gold Nanorods and Gold Nanorod Chains within Smectic Liquid Crystal Topological Defects. ACS Nano, DOI : 10.1021/acsnano.7b01132, 2017.

40. Mouhli, A. ; Ayeb, H. ; Othman, T. ; Fresnais, J. ; Dupuis, V. ; Nemitz, I. R. ; Pendery, J. S. ; Rosenblatt, C. ; Sandre, O. ; Lacaze, E. Influence of a Dispersion of Magnetic and Nonmagnetic Nanoparticles on the Magnetic Fredericksz Transition of the Liquid Crystal 5CB. Phys. Rev. E 2017, 96 (1), 012706.

41. Kanzaki, R. ; Guibert, C. ; Fresnais, J. ; Peyre, V. Dispersion Mechanism of Polyacrylic Acid-Coated Nanoparticle in Protic Ionic Liquid, N,N-Diethylethanolammonium Trifluoromethanesulfonate. J. Colloid Interface Sci. 2018, 10.1016/j.jcis.2018.01.004.

42. Griffete, N. ; Fresnais, J. ; Espinosa, A. ; Taverna, D. ; Wilhelm, C. ; Menager, C. Thermal Polymerization on the Surface of Iron Oxide Nanoparticles Mediated by Magnetic Hyperthermia : Implications for Multi-Shell Grafting and Environmental Applications. ACS Appl. Nano Mater. 2018, 10.1021/acsanm.7b00063.

43. Yadel, C. ; Michel, A. ; Casale, S. ; Fresnais, J. Hyperthermia Efficiency of Magnetic Nanoparticles in Dense Aggregates of Cerium Oxide/Iron Oxide Nanoparticles. Appl. Sci. 2018, 8, 1241.

44. Blin, T. ; Niederberger, A. ; Benyahia, L. ; Fresnais, J. ; Montembault, V. ; Fontaine, L. Thermoresponsive Hybrid Double-Crosslinked Networks Using Magnetic Iron Oxide Nanoparticles as Crossing Points. Polym. Chem. 2018, 10.1039/c8py01006d.

45. Fresnais, J. ; Ma, Q.Q. ; Thai, L. ; Porion, P. ; Levitz, P. ; Rollet, A.L. ; NMR relaxivity of coated and non-coated size-sorted maghemite nanoparticles, Molecular Physics, 2018, 10.1080/00268976.2018.1527410.

46. Cazares-Cortes, E. ; Nerantzaki, M. ; Fresnais, J. ; Wilhelm, C. ; Griffete, N. ; Ménager, C. Magnetic Nanoparticles Create Hot Spots in Polymer Matrix for Controlled Drug Release. Nanomaterials 2018, 8, 850.