Graphene oxide modulates inter-particle interactions in 3D printable soft nanocomposite hydrogels restoring magnetic hyperthermia responses

Structure-dynamics correlations in composite PF127-PEG-based hydrogels; cohesive/hydrophobic interactions determine phase and rheology and identify the role of micelle concentration in controlling 3D extrusion printability

A library of composite polymer networks (CPNs) were formed by combining Pluronic F127, as the primary gelator, with a range of di-acrylate functionalised PEG polymers, which tune the rheological properties and provide UV crosslinkability. A coarse-grained sol-gel room temperature phase diagram was constructed for the CPN library, which identifies PEG-dependent disruption of micelles as leading to liquefication. Small angle X-ray scattering and rheological measurements provide detailed insight into; (i) micelle-micelle ordering; (ii) micelle-micelle disruption, and; (iii) acrylate-micelle disruption; with contributions that depend on composition, including weak PEG chain length and end group effects. The influence of composition on 3D extrusion printability through modulation of the cohesive/hydrophobic interactions was assessed. It was found that only micelle content provides consistent changes in printing fidelity, controlled largely by printing conditions (pressure and feed rate). Finally, the hydrogels were shown to be UV photo-crosslinkable, which further improves fidelity and structural integrity, and usefully reduces the mesh size. Our results provide a guide for design of 3D-printable CPN inks for future biomedical applications.

Hydrogels from a Self-Assembling Tripeptide and Carbon Nanotubes (CNTs): Comparison between Single-Walled and Double-Walled CNTs

Supramolecular hydrogels obtained from the self-organization of simple peptides, such as tripeptides, are attractive soft materials. Their viscoelastic properties can be enhanced through the inclusion of carbon nanomaterials (CNMs), although their presence can also hinder self-assembly, thus requiring investigation of the compatibility of CNMs with peptide supramolecular organization. In this work, we compared single-walled carbon nanotubes (SWCNTs) and double-walled carbon nanotubes (DWCNTs) as nanostructured additives for a tripeptide hydrogel, revealing superior performance by the latter. Several spectroscopic techniques, as well as thermogravimetric analyses, microscopy, and rheology data, provide details to elucidate the structure and behavior of nanocomposite hydrogels of this kind.

Supramolecular Hydrogels from a Tripeptide and Carbon Nano-Onions for Biological Applications

Nanocomposite hydrogels have attracted researchers' attention in recent years to achieve superior performances in a variety of materials applications. In this work, we describe the outcome of three different strategies to combine a self-assembling tripeptide and carbon nano-onions (CNOs), through covalent and non-covalent approaches, into supramolecular and nanostructured hydrogels. Importantly, the tripeptide coated the nano-onions and extended their aqueous dispersions' stability by several hours. Furthermore, CNOs could be loaded in the tripeptide hydrogels at the highest level ever reported for nanocarbons, indicating high compatibility between the components. The materials were formed in phosphate-buffered solutions, thus paving the way for biological applications, and were characterized by several spectroscopic, microscopic, thermogravimetric, and rheological techniques. In vitro experiments demonstrated excellent cytocompatibility.

Emerging Magnetic Fabrication Technologies Provide Controllable Hierarchically-Structured Biomaterials and Stimulus Response for Biomedical Applications

Multifunctional nanocomposites which exhibit well-defined physical properties and encode spatiotemporally-controlled responses are emerging as components for advanced responsive systems. For biomedical applications magnetic nanocomposite materials have attracted significant attention due to their ability to respond to spatially and temporally varying magnetic fields. The current state-of-the-art in development and fabrication of magnetic hydrogels toward biomedical applications is described. There is accelerating progress in the field due to advances in manufacturing capabilities. Three categories can be identified: i) Magnetic hydrogelation, DC magnetic fields are used during solidification/gelation for aligning particles; ii) additive manufacturing of magnetic materials, 3D printing technologies are used to develop spatially-encoded magnetic properties, and more recently; iii) magnetic additive manufacturing, magnetic responses are applied during the printing process to develop increasingly complex structural arrangement that may recapitulate anisotropic tissue structure and function. The magnetic responsiveness of conventionally and additively manufactured magnetic hydrogels are described along with recent advances in soft magnetic robotics, and the categorization is related to final architecture and emergent properties. Future challenges and opportunities, including the anticipated role of combinatorial approaches in developing 4D-responsive functional materials for tackling long-standing problems in biomedicine including production of 3D-specified responsive cell scaffolds are discussed.

Large-Scale Preparation of Micro-Nanofibrous and Fluffy Propylene-Based Elastomer/Polyurethane@Graphene Nanoplatelet Membranes with Breathable and Flexible Characteristics for Wearable Stretchy Heaters

Effective personal thermal management is crucial for protecting human health during cold weather. Therefore, wearable heaters based on electric-heating membranes are one of the most promising devices to become essential appliances in our daily lives. The main challenge toward this goal is the development of electric-heating membranes with adequate breathable, flexible, and stretchable characteristics. In the work presented here, micro-nanofibrous fluffy electric-heating membranes were prepared by coating polyurethane/graphene nanoplatelet (PU@GNP) films onto melt-blown propylene-based elastomer (PBE) micro-nanofibrous membranes via a facile, cheap, and large-scale method consisting of a coating-compressing cyclic process. Investigation of the resulting PBE/PU@GNP membranes showed that the PU@GNP films were uniformly deposited onto the PBE micro-nanofiber surfaces, forming fluffy interconnected conducting channels. By applying a voltage of 36 V to the prepared PBE/PU@GNP membranes, the temperature increased to 69.7 °C, confirming excellent electric-heating features. Moreover, the porosity of the fabricated membrane could be tailored readily by adjusting the coating-compressing cycles. Benefiting from the conducting channels, the PBE/PU@GNP membranes exhibited efficiently regulated air permeability ranging from 212 to 60.2 mm/s, a prominent softness score of 53.8, and an excellent elastic recovery rate of 85.5%. These findings demonstrate that PBE/PU@GNP micro-nanofibrous fluffy membranes may well be suitable for application in electric-heating clothing. The cyclic coating-compressing preparation process may be attractive in industrial manufacturing.

Core-shell Pluronic F127/chitosan based nanoparticles for effective delivery of methotrexate in the management of rheumatoid arthritis

This study was designed to improve oral bioavailability of the methotrexate (MTX) by sustaining its release profile and integration into core-shell polymeric nanoparticles. The self-micellization and ionotropic gelation technique was employed which resulted into spherical shaped nanoparticles (181-417 nm) with encapsulation efficiency of 80.14% to 85.54%. Furthermore, Fourier Transform Infrared Spectroscopy and Differential Scanning Calorimetry analyses were carried out to investigate physicochemical and thermal stability of the produced engineered core shell nanoparticles of the methotrexate. . Entrapment of drug in polymeric core was confirmed by X-ray diffraction analysis. In-vitro sustained release behavior of nanoparticles was observed at pH 6.8 for 48 h while low drug release was observed at pH 1.2 due to pH-responsive nature of Pluronic F127. Acute toxicity study confirmed safety and biocompatible profile of nanoparticles. MTX loaded polymeric nanoparticles ameliorated the pharmacokinetic profile (8 folds greater half-life, 6.26 folds higher AUC_0-t and 3.48 folds higher mean residence time). In vivo study conducted in rat model depicted the improved therapeutic efficacy and healing of arthritis through MTX loaded polymeric nanoparticles, preferentially attributable to high accretion of MTX in the inflamed site. In conclusion, MTX loaded polymeric nanoparticles is an attractive drug delivery strategy for an effective management and treatment of rheumatoid arthritis.

Flake Graphene-Based Nanomaterial Approach for Triggering a Ferroptosis as an Attractive Theranostic Outlook for Tackling Non-Small Lung Cancer: A Mini Review

Lung cancer is a highly aggressive neoplasm that is now a leading cause of cancer death worldwide. One of the major approaches for killing cancer cells is related with activation of apoptotic cell death with anti-cancer drugs. However, the efficiency of apoptosis induction in tumors is limited. Consequently, the development of other forms of non-apoptotic cell death is up to date challenge for scientists worldwide. This situation motivated us to define the aim of this mini-review: gathering knowledge regarding ferroptosis—newly defined programmed cell death process characterized by the excessive accumulation of iron—and combining it with yet another interesting nanomaterial-based graphene approach. In this manuscript, we presented brief information about non-small lung cancer and ferroptosis, followed by a section depicting the key-features of graphene-based nanomaterials influencing their biologically relevant properties.