Mechanical, Electrical and Magnetic Properties of Ferrogels with Embedded Iron Oxide Nanoparticles Obtained by Laser Target Evaporation: Focus on Multifunctional Biosensor Applications

Abstract

Hydrogels are biomimetic materials widely used in the area of biomedical engineering and biosensing. Ferrogels (FG) are magnetic composites capable of functioning as magnetic field sensitive transformers and field assisted drug deliverers. FG can be prepared by incorporating magnetic nanoparticles (MNPs) into chemically crosslinked hydrogels. The properties of biomimetic ferrogels for multifunctional biosensor applications can be set up by synthesis. The properties of these biomimetic ferrogels can be thoroughly controlled in a physical experiment environment which is much less demanding than biotests. Two series of ferrogels (soft and dense) based on polyacrylamide (PAAm) with different chemical network densities were synthesized by free-radical polymerization in aqueous solution with N,N’-methylene-diacrylamide as a cross-linker and maghemite Fe2O3 MNPs fabricated by laser target evaporation as a filler. Their mechanical, electrical and magnetic properties were comparatively analyzed. We developed a giant magnetoimpedance (MI) sensor prototype with multilayered FeNi-based sensitive elements deposited onto glass or polymer substrates adapted for FG studies. The MI measurements in the initial state and in the presence of FG with different concentrations of MNPs at a frequency range of 1–300 MHz allowed a precise characterization of the stray fields of the MNPs present in the FG. We proposed an electrodynamic model to describe the MI in multilayered film with a FG layer based on the solution of linearized Maxwell equations for the electromagnetic fields coupled with the Landau-Lifshitz equation for the magnetization dynamics.

Application of New Sodium Vinyl Sulfonate–co-2-Acrylamido-2-me[thylpropane Sulfonic Acid Sodium Salt-Magnetite Cryogel Nanocomposites for Fast Methylene Blue Removal from Industrial Waste Water

“…These data elucidate the increasing interaction between iron cations with the amide and sulfonate groups of VS/AMPS matrices and reduces the aggregation of magnetite that reduces their sizes into the VS/AMPS cryogel. Furthermore, the free volume in the highly crosslinked VS/AMPS cryogels reduces the growing of magnetite to produce ultrafine nanoparticles [ 11 , 29 , 30 , 31 , 32 ]. The thermal stability of the cryogel and its composites with magnetite is investigated from the TGA curves ( Figure 4 ).…”

“…In this work, it is proposed that the presence of nanomaterials during the network gelation of the crosslinked cryogels may be used to enhance the mechanical properties and porosity of the cryogels. The preparation of ferrogel composites, based on a magnetic oxides polymer matrix, is the target of the present work, owing to their biocompatibility as a drug delivery option [ 10 , 11 , 12 ] and as an environmentally friendly effective adsorbent that improves the mechanical properties of the polymer matrix [ 12 ].…”

Effects of Constant Magnetic Field to the Proliferation Rate of Human Fibroblasts Grown onto Different Substrates: Tissue Culture Polystyrene, Polyacrylamide Hydrogel and Ferrogels γ-Fe2O3 Magnetic Nanoparticles

“…Recently, we have proposed a new approach for cultivation of selected cell cultures, which might be useful for regenerative medicine, drug delivery and biosensor applications. This approach is based on the usage of synthetic hydrogels and ferrogels as biomimetic materials [3][4][5]. Human dermal fibroblast cultures were grown on the surface of polyacrylamide hydrogels and ferrogels [6] and their adhesive and proliferative activities were studied.…”

Static magnetization of immobilized, weakly interacting, superparamagnetic nanoparticles

“…Embedding a large number of such particles into a matrix makes it possible to control the properties of a composite material using an external magnetic field, and it is this control which is exploited in modern technologies. So-called magnetic soft matter includes ferrofluids, 1 magnetorheological fluids, magnetic elastomers [2][3][4][5] and ferrogels, [6][7][8] ferronematic liquid crystals, [9][10][11] and various biocompatible magnetic suspensions, [12][13][14][15][16] which are applied in targeted drug delivery and magnetic hyperthermia. [17][18][19][20][21][22] In addition to technical and biomedical applications, magnetic nanoparticle ensembles are also useful in colloid technology, because of interesting self-assembly processes.…”