Porous materials are widely used in industry for applications that include chemical separations and gas scrubbing. These materials are typically porous solids, though the liquid state can be easier to manipulate in industrial settings. The idea of combining the size-and shape-selectivity of porous domains with the fluidity of liquids is a promising one and porous liquids composed of functionalized organic cages have recently attracted attention. Here, we describe an ionic-liquid, porous, tetrahedral coordination cage. Complementing the gas-binding observed in other porous liquids, this material also encapsulates non-gaseous guestsshape-and size-selectivity was observed for a series of alcohol isomers. Three gaseous guests, chlorofluorocarbons CFC-11, CFC-12, and CFC-13, were also shown to be taken up by the liquid coordination cage with an affinity increasing with their size. We hope that these findings will lead to the synthesis of other porous liquids whose guest-uptake properties may be tailored to fulfil specific functions. Recent work has shown that persistent cavities can be engineered into liquids, lending them permanent porosity. These new materials were initially proposed by James in 2007 1 , who recognised three distinct types of them. The simplest of these, Type I permanently porous liquids, consist of rigid hosts with empty cavities that are liquid in their neat state 2,3 , without requiring an additional solvent for fluidity 4-7. Metalorganic frameworks (MOFs) have also been observed to form liquid phases that are inferred to be porous 8,9 , although the high temperatures required preclude guest binding. Previously reported examples of porous liquids have included surface-modified hollow silica spheres 2 and hollow carbon spheres 3 , crown ether-functionalised organic cages 5 , and dispersions 4, 6 or slurries 7 of porous framework materials in ionic liquids. To date, applications of these materials have focussed on gas storage and separation 2,10,11. However, we are not aware of the binding of guest molecules larger than carbon dioxide or methane inside the cavities of porous liquids, restricting the potential application of these

A physical hydrogel cross-linked via the host-guest interactions of cucurbit[8]uril and utilised as an implantable drug-delivery vehicle for the brain is described herein. Constructed from hyaluronic acid, this hydrogel is biocompatible and has a high water content of 98%. The mechanical properties have been characterised by rheology and compared with the modulus of human brain tissue demonstrating the production of a soft material that can be moulded into the cavity it is implanted into following surgical resection. Furthermore, effective delivery of therapeutic compounds and antibodies to primary human glioblastoma cell lines is showcased by a variety of in vitro and ex vivo viability and immunocytochemistry based assays.

The clinical outcomes and 5-year survival rate for patients with glioblastoma (GB) make it among the most pernicious and challenging diseases to treat. Despite all the resources, time, and talent focused on developing targeted and/or local delivery technologies by the biomaterials community for GB, the clinical performance of the FDA-approved therapy carmustine ((BCNU)-loaded polyanhydride wafers) and clinical trials of other material approaches have been discouraging. As disappointing is the remarkably stagnant clinical translation of next-generation material approaches for GB. Despite encouraging preclinical results from hydrogels and modified wafer formulations loaded with more efficacious chemotherapies, a total of zero have completed even a phase I clinical trial. Other strategies, including convection-enhanced delivery, microsphere formulations, or drug-loaded nanoparticles have seen limited, albeit some, translation into the clinic with mixed results. This lackluster progress can be attributed, in part, to the paucity of communication between material scientists, biomedical scientists, and clinicians. When examining the purported clinical relevance of embedding certain material properties into formulations, it is clear that some widely known truths about the nature of GB progression among clinicians have not reached the biomaterials community.Furthermore, a closer examination of the lessons from the BCNU wafers and other clinical trials of GB drug delivery materials may enrich and inspire materials scientists to create new systems that satisfy unmet medical needs identified by the clinical community. In tandem, clinicians and biomedical scientists may benefit from a short review highlighting the biocompatibility, safety, longevity, kinetics, tunability, and efficacy of promising new drug delivery materials without inundation by chemical and physical characterizations or discussions.Another key challenge in treating GB is an incomplete understanding of disease pathophysiology, such as mechanisms driving intrinsic and adaptive GB cell chemoresistance. A combined approach where biomedical scientists and material To date, the clinical outcomes and survival rates for patients with glioblastoma (GB) remain poor. A promising approach to disease-modification involves local delivery of adjuvant chemotherapy into the resection cavity, thus circumventing the restrictions imposed by the blood-brain barrier. The clinical performance of the only FDA-approved local therapy for GB [carmustine (BCNU)-loaded polyanhydride wafers], however, has been disappointing. There is an unmet medical need in the local treatment of GB for drug delivery vehicles that provide sustained local release of small molecules and combination drugs over several months. Herein, key quantitative lessons from the use of local and systemic adjuvant chemotherapy for GB in the clinic are outlined, and it is discussed how these can inform the development of next-generation therapies. Several recent approaches are highlighted, and it is proposed that long...

Supramolecular hyaluronic acid hydrogels formed via 2 : 1 homoternary complexes of coumarin and cucurbit[8]uril can reversibly toggle between physical and covalent states.

Interactive materials are at the forefront of current materials research with few examples in the literature. Researchers are inspired by nature to develop materials that can modulate and adapt their behavior in accordance with their surroundings. Stimuli‐responsive systems have been developed over the past decades which, although often described as “smart,” lack the ability to act autonomously. Nevertheless, these systems attract attention on account of the resultant materials' ability to change their properties in a predicable manner. These materials find application in a plethora of areas including drug delivery, artificial muscles, etc. Stimuli‐responsive materials are serving as the precursors for next‐generation interactive materials. Interest in these systems has resulted in a library of well‐developed chemical motifs; however, there is a fundamental gap between stimuli‐responsive and interactive materials. In this perspective, current state‐of‐the‐art stimuli‐responsive materials are outlined with a specific emphasis on aqueous macroscopic interactive materials. Compartmentalization, critical for achieving interactivity, relies on hydrophobic, hydrophilic, supramolecular, and ionic interactions, which are commonly present in aqueous systems and enable complex self‐assembly processes. Relevant examples of aqueous interactive materials that do exist are given, and design principles to realize the next generation of materials with embedded autonomous function are suggested.