Polymers with the same chemical composition can provide different properties by reducing the dimension or simply by altering their nanostructure. The recent literature reports hundreds of examples of advanced methods in the fabrication of polymer nanostructures accomplished following a variety of approaches, such as soft lithography, self-assembly routes, template assisted methods, etc. Polymer nanostructures with modulated morphologies and properties can be easily achieved from anodized aluminum oxide (AAO) template assisted methods. In the last decade, fabrication of polymer nanostructures in the nanocavities of AAOs has increased in interest since it allows the control and tailoring of the dimensions of a huge number of polymer and polymer-based composites materials. The fact that polymer dimensions may be adjusted allows the study of size-dependent properties. Moreover, using AAO template methods, modulated polymer nanostructures may be designed for specific applications. This review presents recent new insights in the fabrication methods of polymer nanostructures from hard porous AAO templates, with emphasis on the study of polymer structure/property relationships on the nanometric length scale, stressing potential interests in relevant applications. The discussion includes (i) a description of the anodizing methods and strategies to obtain AAO templates with adjusted dimensions; (ii) a summary of different infiltration methods, starting with the infiltration of a polymeric fluid (melt or solution) into the nanocavities of the AAO template, to conform a great number of the polymer nanostructures with different morphologies, the approach to obtain directly polymer nanostructures by in-situ polymerization of a monomer within AAO nanocavities and the effect of confinement in the AAO nanoreactor on the polymerization kinetics; (iii) an overview of the effects of confinement on structural aspects, dynamical processes and the mechanical, thermal and rheological properties of the polymer; (iv) examples of polymer nanostructures as precursors in bio-, adhesion, optical and electrical related applications; and finally (v) a summary of conclusions and suggested challenges.Acknowledgments Authors are gratefully acknowledged to the Ministerio de Economía y Competitividad for their financial support (MAT2011-24797 and MAT2014-53437). Rebeca Hernández thanks MEC for a Ramon y Cajal contract. Jaime Martína cknowledges support from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement no. 654682Peer Reviewe

Hyaluronic acid (HA) hydrogels display a wide variety of biomedical applications ranging from tissue engineering to drug vehiculization and controlled release. To date, most of the commercially available hyaluronic acid hydrogel formulations are produced under conditions that are not compatible with physiological ones. This review compiles the currently used approaches for the development of hyaluronic acid hydrogels under physiological/mild conditions. These methods include dynamic covalent processes such as boronic ester and Schiff-base formation and click chemistry mediated reactions such as thiol chemistry processes, azide-alkyne, or Diels Alder cycloaddition. Thermoreversible gelation of HA hydrogels at physiological temperature is also discussed. Finally, the most outstanding biomedical applications are indicated for each of the HA hydrogel generation approaches.

Chitosan nanoparticles (CSNPs) ionically crosslinked with tripolyphosphate salts (TPP) were employed as nanocarriers in combined drug delivery and magnetic hyperthermia (MH) therapy. To that aim, three different ferrofluid concentrations and a constant 5-fluorouracil (5-FU) concentration were efficiently encapsulated to yield magnetic CSNPs with core-shell morphology. In vitro experiments using normal cells, fibroblasts (FHB) and cancer cells, human glioblastoma A-172, showed that CSNPs presented a dose-dependent cytotoxicity and that they were successfully uptaken into both cell lines. The application of a MH treatment in A-172 cells resulted in a cell viability of 67-75% whereas no significant reduction of cell viability was observed for FHB. However, the A-172 cells showed re-growth populations 4h after the application of the MH treatment when CSNPs were loaded only with ferrofluid. Finally, a combined effect of MH and 5-FU release was observed with the application of a second MH treatment for CSNPs exhibiting a lower amount of released 5-FU. This result demonstrates the potential of CSNPs for the improvement of MH therapies.