Incorporating nanoparticles into injectable hydrogels is a well-known technique for improving the mechanical properties of these materials. However, significant differences in the mechanical properties of the polymer matrix and the nanoparticles can result in localized stress concentrations at the polymer–nanoparticle interface. This situation can lead to problems such as particle–matrix debonding, void formation, and material failure. This work introduces boronic acid/boronate ester dynamic covalent bonds (DCBs) as energy dissipation sites to mitigate stress concentrations at the polymer–nanoparticle interface. Once boronic acid groups were immobilized on the surface of SiO2 nanoparticles (SiO2-BA) and incorporated into an alginate matrix, the nanocomposite hydrogels exhibited enhanced viscoelastic properties. Compared to unmodified SiO2 nanoparticles, introducing SiO2 nanoparticles with boronic acid on their surface improved the structural integrity and stability of the hydrogel. In addition, nanoparticle-reinforced hydrogels showed increased stiffness and deformation resistance compared to controls. These properties were dependent on nanoparticle concentration. Injectability tests showed shear-thinning behavior for the modified hydrogels with injection force within clinically acceptable ranges and superior recovery.
Herein, we investigated hydrogels composed of boronic-acid-functionalized alginate and blended with polyvinyl alcohol (PVA) of different molecular weights to control the release of metoclopramide hydrochloride as a function of pH and shear stress. The functionalization of alginate introduced dynamic covalent bonding and pH-responsive properties that can modulate network connectivity. The study investigated the viscoelastic properties of the hydrogels, their drug release profiles, and their responsiveness to changes in pH and shear forces. The results showed that a higher PVA molecular weight and alkaline pH conditions increased hydrogel viscosity and stiffness due to a more stable and interconnected network structure than acidic pH. Metoclopramide release revealed that the hydrogels exhibited pH-responsive drug release behavior. The drug was more readily released under acidic conditions due to the instability of sp2-hybridized boronate ester bonds. The influence of shear forces on the release of metoclopramide was also investigated at shear rates of 1, 10, and 100 s−1, revealing their effect on matrix stiffening. Research shows that AlgBA/PVA hydrogels have unique properties, such as dynamic covalent bonding, that make them sensitive to external mechanical forces. This sensitivity makes them ideal for applications where physiological conditions trigger drug release.
Herein, we investigated hydrogels composed of boronic Acid functionalized alginate and blended with polyvinyl alcohol of different molecular weights to control the release of metoclopramide hydrochloride (MTC) as a function of pH and shear stress. The functionalization of alginate introduced dynamic covalent bonding and pH-responsive properties that can modulate network connectivity. The study investigated the viscoelastic properties of the hydrogels, their drug release profiles, and their responsiveness to changes in pH and shear forces. The results showed higher PVA molecular weight and alkaline pH conditions increased hydrogel viscosity and stiffness due to a more stable and interconnected network structure than acidic pH. Metoclopramide release revealed that the hydrogels exhibited pH-responsive drug release behavior. The drug was more readily released under acidic conditions due to the instability of sp2-hybridized boronate ester bonds. The influence of shear forces on the release of metoclopramide was also investigated at shear rates of 1, 10, and 100 s-1, revealing their effect on matrix stiffening. The research shows that AlgBA/PVA hydrogels have unique properties, such as dynamic covalent bonding, that make them sensitive to external mechanical forces. This sensitivity makes them ideal for applications where physiological conditions trigger drug release
Emerging technologies in human–machine interfacing increasingly aim to develop solutions that naturally conform to the body's unique characteristics. Ergonomics and electrical performance in cutaneous sensing are crucial for accurate and reliable translation of biosignals. However, current sensor technologies are often constrained by bulky designs and hydrogel‐assisted skin interfaces that are prone to drying out, necessitate frequent replacement, and contribute to excessive electronic waste generation. In this study, we introduce the fabrication of mechanically soft, breathable sponge electrodes coated with a recycled conductive polymer, offering a gel‐free, skin‐conforming cutaneous interface. These electrodes are designed to feature bioinspired interface properties and high skin comfort due to their porous structures. When compared with electrodes made from pristine materials, the recycled versions demonstrate comparable high‐fidelity biopotential acquisition during simultaneous cardiac and low‐amplitude brain signal recordings. This work marks a significant step toward the development of ergonomic interfaces for long‐term health monitoring while adopting a sustainable approach to technological development.
1 September 2026 in Neuromorphic Computing and Engineering
Organic materials offer a transformative opportunity for smart edge applications due to their compatibility with large-area manufacturing, mechanical flexibility, scalability at low cost, and potentially reduced environmental impact. While their use in display technologies is now well-established, their integration into other applications domains is still in its early stages. Significant progress has been made in the development of materials for organic neuromorphic devices, enabling explorations of applications in neuroscience, soft robotics and healthcare. Additional promising directions include photonics, optoelectronics and memories. The goal of this roadmap is to consider how the properties of these materials can be leveraged to implement alternative computing methodologies to enable a new generation of organic technologies.