Bioinspired Janus particles for hydrophobic modification of hydrogels with photothermal antibacterial capability

Janus structure hydrogels: recent advances in synthetic strategies, biomedical microstructure and (bio)applications

Janus structure hydrogels (JSHs) are novel materials. Their primary fabrication methods and various applications have been widely reported. JSHs are primarily composed of Janus particles (JNPs) and polysaccharide components. They exhibit two distinct physical or chemical properties, generating intriguing characteristics due to their asymmetric structure. Normally, one side (adhesive interface) is predominantly constituted of polysaccharide components, primarily serving excellent adhesion. On the other side (functional surface), they integrate diverse functionalities, concurrently performing a plethora of synergistic functions. In the biomedical field, JSHs are widely applied in anti-adhesion, drug delivery, wound healing, and other areas. It also exhibits functions in seawater desalination and motion sensing. Thus, JSHs hold broad prospects for applications, and they possess significant research value in nanotechnology, environmental science, healthcare, and other fields. Additionally, this article proposes the challenges and future work facing these fields.

Modulation of the dissolution with ASP from a supersaturated solution on a bionic platform for gout pathology crystals

The core to the treatment of gout is the elimination of pathologic crystal, monosodium urate monohydrate (MSUM). The primary treatment available is to gradually dissolve the "culprit crystals" by lowering the blood uric acid concentration with medications, which often takes a long time and in severe cases must still be treated surgically. Herein, we developed a dynamic bionic platform based on a hydrogel composite membrane (HCM) to screen the direct facilitated solubilization of MSUM crystals by small organic molecules in bionic saturated, or even supersaturated, solutions. The customized and biologically safe (NAGA/PEGDA/NIPAM) HCM, which is consistent with the main amino acid composition of articular cartilage, well mimics the entire process of organic molecules leading to the dissolution of MSUM crystals in the joint system. With the verifications of this platform, it is shown that l-aspartic acid (ASP) significantly promotes the dissolution of MSUM crystals not only in saturated but also in supersaturated solutions. Furthermore, a novel mechanism called "crane effect" was used to explain this "dissolution effect" of ASP on MSUM, which stems from the ability of ASP to lock onto the surface of MSUM crystals through hydrogen bonding by virtue of its two carboxyl groups, and simultaneously its amino group lifts the uric acid molecules from the surface of MSUM crystals by virtue of interactions of hydrogen bonding. The results of bulk crystallization, scanning electron microscopy (SEM), powder X-diffraction (PXRD), and density-functional theory (DFT) studies are quantitatively consistent with this hypothetical "crane effect" mechanism. Hence, this HCM-based functional platform could provide entirely novel ideas and methods for drug design and screening for the treatment of pathological crystal diseases of gout.

Controllable Preparation and Research Progress of Photosensitive Antibacterial Complex Hydrogels

Hydrogels are materials consisting of a network of hydrophilic polymers. Due to their good biocompatibility and hydrophilicity, they are widely used in biomedicine, food safety, environmental protection, agriculture, and other fields. This paper summarizes the typical complex materials of photocatalysts, photosensitizers, and hydrogels, as week as their antibacterial activities and the basic mechanisms of photothermal and photodynamic effects. In addition, the application of hydrogel-based photoresponsive materials in microbial inactivation is discussed, including the challenges faced in their application. The advantages of photosensitive antibacterial complex hydrogels are highlighted, and their application and research progress in various fields are introduced in detail.

Tailored hydrogel composite membrane for the regulated crystallization of monosodium urate monohydrate within coffee's metabolites system

Herein, a facile bionic research platform with fabricated hydrogel composite membrane (HCM) is constructed to uncover the effects of the main components of coffee's metabolites on MSUM crystallization. Tailored and biosafety polyethylene glycol diacrylate/N-isopropyl acrylamide (PEGDA/NIPAM) HCM allows the proper mass transfer of coffee's metabolites and can well simulate the process of coffee's metabolites acting in the joint system. With the validations of this platform, it is shown that chlorogenic acid (CGA) can hinder the MSUM crystals formation from 45 h (control group) to 122 h (2 mM CGA), which is the most likely reason that reduces the risk of gout after long-term coffee consumption. Molecular dynamics simulation further indicates that the high interaction energy (E_int) between CGA and MSUM crystal surface and the high electronegativity of CGA both contribute to the restraint of MSUM crystal formation. In conclusion, the fabricated HCM, as the core functional materials of the research platform, presents the understanding of the interaction between coffee consumption and gout control.

Self-adhesive Hyaluronic Acid/Antimicrobial Peptide Composite Hydrogel with Antioxidant Capability and Photothermal Activity for Infected Wound Healing

Bacterial infection can delay wound healing, causing wounds to deteriorate and even threatening the patient's life. Recently, although many composite hydrogels as wound dressing have been developed, it is still highly desired to construct photothermal hydrogels with antimicrobial and antioxidant properties to accelerate the infected wound healing. In this work, we develop a hyaluronic acid (HA)-based composite hydrogel consisting of a dopamine-substituted antimicrobial peptide (DAP) and Iron (III) ions, which exhibits photothermal-assisted promotion and acceleration of healing process of bacteria-infected wounds. DAP, serving as both antimicrobial agent and ROS-scavenger, forms Schiff's base bonds with aldehyde hyaluronic acid (AHA) and iron-catechol coordination bonds to reinforce the composite hydrogel. The presence of Fe³⁺ can also promote covalent polymerization of dopamine, which endows the hydrogel with photothermal capacity. The in vitro and in vivo experiments prove that the composite hydrogel can effectively accelerate the infected wound healing process, including antibacterial, accelerated collagen deposition and re-epithelization. This study suggests that the multifunctional composite hydrogel possesses remarkable potential for bacteria-infected wound healing by combining inherent antimicrobial activity, antioxidant capability and photothermal effect. This article is protected by copyright. All rights reserved.