Functional Nanogels as a Route to Interpenetrating Polymer Networks with Improved Mechanical Properties

Insights into Targeted and Stimulus-Responsive Nanocarriers for Brain Cancer Treatment

Brain cancers, especially glioblastoma multiforme, are associated with poor prognosis due to the limited efficacy of current therapies. Nanomedicine has emerged as a versatile technology to treat various diseases, including cancers, and has played an indispensable role in combatting the COVID-19 pandemic as evidenced by the role that lipid nanocarrier-based vaccines have played. The tunability of nanocarrier physicochemical properties -including size, shape, surface chemistry, and drug release kinetics- has resulted in the development of a wide range of nanocarriers for brain cancer treatment. These nanocarriers can improve the pharmacokinetics of drugs, increase blood-brain barrier transfer efficiency, and specifically target brain cancer cells. These unique features would potentially allow for more efficient treatment of brain cancer with fewer side effects and better therapeutic outcomes. This review provides an overview of brain cancers, current therapeutic options, and challenges to efficient brain cancer treatment. The latest advances in nanomedicine strategies are investigated with an emphasis on targeted and stimulus-responsive nanocarriers and their potential for clinical translation.

Solid-State Cholesteric Liquid Crystals as an Emerging Platform for the Development of Optical Photonic Sensors

Over the past decade, solid-state cholesteric liquid crystals (CLCsolid ) have emerged as a promising photonic material, heralding new opportunities for the advancement of optical photonic biosensors and actuators. The periodic helical structure of CLCsolid s gives rise to their distinctive capability of selectively reflecting incident radiation, rendering them highly promising contenders for a wide spectrum of photonic applications. Extensive research is conducted on utilizing CLCsolid 's optical characteristics to create optical sensors for bioassays, diagnostics, and environmental monitoring. This review provides an overview of emerging technologies in the field of interpenetrating polymeric network-CLCsolid (IPN) and CLCsolid -based optical sensors, including their structural designs, processing, essential materials, working principles, and fabrication methodologies. The review concludes with a forward-looking perspective, addressing current challenges and potential trajectories for future research.

"Fatigue-Crack Propagation Behavior in Microcapsule-Containing Self-Healing Polymeric Networks"

Over the last years, research on the design of dental self-healing polymers has grown dramatically. It is related to the promising potential of maximizing the clinical lifespan of dental restorations that this strategy holds. In this manuscript, the microcapsule-based strategy is innovated by incorporating the high toughness component N,N-Dimethylacrylamide (DMAM) into the healing agent systems and analyzing in-depth the change in crack propagation behavior induced by the addition of microcapsules into the highly crosslinked polymeric network. In general, the addition of the hydrophilic and high vapor pressure DMAM into the healing agent systems imposed a challenge for the microencapsulation, which highlighted the importance of tailoring the properties of the capsules' shells according to the core composition. The addition of DMAM as cushioning agent proved to be a successful strategy since it resulted in increased G'/G" crossover time from 0.06 (control) to 0.57 s and decreased storage modulus from 8.0 (control) to 0.5GPa. In addition, the incorporation of microcapsules within the polymerized networks provided obstacles to crack propagation, which translated to an overall reinforcement of the polymeric network, as evidenced by the increase in toughness up to 50 % and energy required to propagate cracks up to 100 % in systems containing DMAM at 20 wt%.

Resin-Based Composites for Direct and Indirect Restorations: Clinical Applications, Recent Advances, and Future Trends

Continuous advancements in resin-based composites can make selection of the appropriate system a daunting task for the clinician. This review aims to simplify this process and clarify some new or controversial topics. Various types of composites for direct and indirect applications are discussed, including microfilled and microhybrid composites, nanocomposites, single shade, bulk fill, fiber-reinforced, high temperature/high pressure processed, CAD/CAM, and three-dimensional printable composites. Recent material advancements that lead to improved seal and toughness, degradation resistance, antimicrobial and self-healing capabilities are presented. Future directions are highlighted, such as the development of "smart" materials that are able to interact with the host environment.

Double Networks of Liquid-Crystalline Elastomers with Enhanced Mechanical Strength

Liquid-crystalline elastomers (LCEs) are frequently used in soft actuator development. However, applications are limited because LCEs are prone to mechanical failure when subjected to heavy loads and high temperatures during the working cycle. A mechanically tough LCE system offers larger work capacity and lower failure rate for the actuators. Herein, we adopt the double-network strategy, starting with a siloxane-based exchangeable LCE and developing a series of double-network liquid-crystalline elastomers (DN-LCEs) that are mechanically tougher than the initial elastomer. We incorporate diacrylate reacting monomers to fabricate DN-LCEs, some of which have the breaking stress of 40 MPa. We incorporate thermoplastic polyurethane to fabricate a DN-LCE, achieving an enormous ductility of 90 MJ/m³. We have also attempted to utilize the aza-Michael chemistry to make a DN-LCE that retains high plasticity because of several bond-exchange mechanisms; however, it failed to produce a stable reprocessable LCE system using conventional ester-based reactive mesogens. Each of these DN-LCEs exhibits unique features and characteristics, which are compared and discussed.