The use of multifunctional nanoparticles (NPs), usually in the range of 3–100 nm, with their newly discovered properties – such as superparamagnetic (SPM) behaviour, enhancement of activity and selectivity in catalytic processes and localised surface plasmon resonance (LSPR) – offers new technical possibilities for biomedical applications such as magnetic hyperthermia (MH), plasmonic photothermal therapy (PPTT) and enhanced magnetic resonance imaging (MRI). In addition, the small size of NPs presents a unique opportunity to interfere, in a highly localised and specific way, with natural processes involving viruses, bacteria or cells and allows interference in the development of complex diseases like many types of cancer and neuropathies (Alzheimer's, Parkinson's, Kreutzer–Jacobs'). The design of biological applications based on MH is a chemical challenge and core@shell structures are most often used to endow NPs with multifunctional abilities. The success of such MH‐based biological applications depends on the magnetic functionality of the core as well as the properties of the surface shell in direct interaction with the biological medium. In this review we will describe the most important methodologies developed to synthesise magnetic core@shell nanostructures and their MH applications.

In this paper, novel magnetic silica nanocomposites were prepared by anchoring magnetite nanoparticles onto the outer surface of mesoporous SBA-15 silica; the magnetic nanoparticles were prepared by microemulsion and solvothermal methods, varying the synthesis conditions in order to control the final physicochemical, textural and magnetic properties. The morphology and mesostructure of the materials were characterized by X-ray diffraction (XRD), Fourier-Transform Infrared Spectroscopy (FTIR), N 2 adsorption-desorption, and Transmission and Scanning Electron Microscopy (TEM and SEM). Magnetic silica nanocomposites feature a two-dimensional hexagonal arrangement constituted by a homogeneous pore channel system with diameters between 13 and 18 nm and a Brunauer-Emmett-Teller (BET) surface area higher than 260 m 2 g À1 . The different morphologies of the samples are given by the presence of diverse magnetic nanoparticle arrangements covalently linked onto the outer surface of the mesoporous silica rods. This confers on them a superparamagnetic behaviour with a magnetic response between 50-80 emu g À1 , even though the weight percent of magnetite present in the samples does not exceed 21.7%. In addition, the magnetic nanocomposites exhibit magnetic hyperthermia with moderate Specific Absorption Rate (SAR) values.

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Neurological diseases of diverse aetiologies have significant effects on the quality of life of patients. The limited self-repairing capacity of the brain is considered to be the origin of the irreversible and progressive nature of many neurological diseases. Therefore, neuroprotection is an important goal shared by many clinical neurologists and neuroscientists. In this review, we discuss the main obstacles that have prevented the implementation of experimental neuroprotective strategies in humans and propose alternative avenues for the use of neuroprotection as a feasible therapeutic approach. Special attention is devoted to nanotechnology, which is a new approach for developing highly specific and localized biomedical solutions for the study of the multiple mechanisms involved in stroke. Nanotechnology is contributing to personalized neuroprotection by allowing us to identify mechanisms, determine optimal therapeutic windows, and protect patients from brain damage. In summary, multiple aspects of these new players in biomedicine should be considered in future in vivo and in vitro studies with the aim of improving their applicability to clinical studies.

Electrospun fibers based on biodegradable polyanionic or polycationic biopolymers are highly beneficial for biomedical applications. In this work, electrospun nanofibers made from poly(epsilon caprolactone) (PCL), chitosan (CS) and κ-carrageenan (κ-C) were successfully fabricated using several mixtures of benign solvents containing formic acid (FA) and acetic acid (AA). The addition of κ-carrageenan improved the preparation procedure for the production of PCL/CS fibers by electrospinning. Moreover, a polymer mixture was selected to be stored at -20 °C for one month with the purpose to study the properties of the resulting fiber mat. The results indicated that fiber characteristics were not seriously compromised compared to the ones of those fabricated with the original solution, which represents an important reduction in produced waste. Thus, the interactions that occur between positively and negatively charged hydrophilic polysaccharides might induce higher stability to the linear aliphatic polyester in the polymer mixture. All fiber mats were morphologically, physico-chemically and mechanically characterized, showing average fiber diameters in the nano scale. A direct cell viability assay using ST-2 cells demonstrated cell proliferation after 7 days of incubation for all prepared fiber mats, confirming their suitability as potential candidates for bone tissue engineering and wound healing applications.

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The development of scaffolds with suitable physicochemical and mechanical properties allowing for the structural regeneration of injured bone and recovery of the natural biological functionality is still a challenge in the tissue engineering field. Nanostructured materials with added theranostic abilities, together with an interconnected hierarchy of pores, offer the possibility to provide a new generation of bone implants. In this work, scaffolds with highly porous and resistant threedimensional structures have been successfully developed by homogeneously embedding mesoporous silica nanostructures in a bioactive matrix of chitosan/κ-carrageenan. Moreover, magnetite (Fe 3 O 4 ) nanoparticles were also added to the mesoporous scaffold to include additional magnetic functionalities for diagnostic or therapeutic actions. The complete physicochemical characterization shows mesoporous materials with a wide range of interconnected pores, remarkable surface roughness, and large effective surface area, suitable for cell adhesion. In accordance to these properties, a simvastatin loading and release assay showed high loading capacities and sustained release over a long period of time. Together with a suitable resistance against degradation and biocompatible performance assessed by cell viability assays, these scaffolds show interesting features for delivering drugs with activity in bone regeneration processes.