Biomacromolecules最新文献

Ionogels, as soft ionic conductors, face synthesis challenges including toxicity, complexity, and high energy consumption. Herein, we present a green one-pot strategy that effectively dissolves cellulose and undergoes sunlight-induced photopolymerization to form ionogels without the need for cross-linkers or initiators. 1-Butyl-3-methylimidazolium chloride ([BMIM]Cl), as the solvent, enables the disruption of the extensive hydrogen-bond network of cellulose, resulting in rapid and complete dissolution. Subsequent one-step photopolymerization, which proceeds solely under sunlight, simultaneously drives in situ cross-linking and a controlled phase separation process, yielding high-performance ionogels. Importantly, the resulting cellulose ionogel exhibits superior fracture strength (2.75 MPa), high toughness (18.4 MJ m^-3), and strong adhesion (6.6 MPa), ameliorating the traditional trade-off between mechanical strength and adhesion capabilities. This work develops an integrated ionogel platform as a soft TENG electrode for human motion monitoring, informing the design of sustainable self-powered electronics.

The concurrence of drug-resistant infections and malignant tumors poses a serious challenge to clinical treatment, demanding multifunctional biomaterials with integrated therapeutic efficacy. In this study, we developed D-peptide engineered double-network (DN) hydrogels by combining a mechanically robust GelMA framework with a bioactive D-peptide (ik3) that exhibited broad-spectrum antibacterial and antitumor properties. The DN architecture provides improved toughness and stability under physiological conditions, while the incorporation of the ik3 peptide enhances proteolytic resistance and ensures sustained bioactivity. In vitro experiments demonstrated efficient inhibition of both Gram-negative and Gram-positive bacterial growth as well as apoptosis induction in a variety of tumor cell lines. Overall, these findings support D-peptide modified DN hydrogels as a promising multifunctional platform for synergistic infection control and tumor therapy.

Poly(3-hydroxybutyrate) (PHB) has long been recognized as a promising biobased and potentially biodegradable polymer; however, its brittleness and narrow processing window limit broader implementation. Copolymerization with 3-hydroxyvalerate (3HV) improves flexibility and thermal behavior, yet controlling elevated 3HV incorporation in wild-type strains remains metabolically constrained. This work systematically investigates poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBHV) biosynthesis in Cupriavidus necator H1 G⁺3 DSM 545 as a benchmark production system, focusing on process limitations rather than record composition. The influence of cultivation mode (batch vs fed-batch), precursor chemistry (valeric acid vs sodium valerate), and pulse concentration was evaluated in relation to copolymer composition, molar mass distribution, and thermal properties. Under optimized conditions, 3HV contents up to 64 mol % were obtained. Increasing valeric acid concentrations led to reduced cell density and decreased 3HV incorporation, revealing a narrow precursor tolerance window. Using sodium valerate tends to promote biomass formation and 3HB biosynthesis at the expense of 3HV incorporation. A rapid, nondestructive FTIR method was developed to estimate 3HV molar fraction. These results clarify intrinsic metabolic boundaries governing 3HV incorporation and establish a framework for controlled structure-property investigation of PHBHV copolymers.

Gelatin methacryloyl (GelMA) is an essential biomaterial for 3D bioprinting due to its excellent biocompatibility and easily tunable physical properties. GelMA quality strongly depends on the number of methacrylic groups introduced during the synthesis. We present a direct UV assay for routine quantification of methacrylic groups in GelMA. The accuracy and precision of the method are comparable to those of NMR techniques. Moreover, the method is independent of sample concentration and adapted for gelatin from various sources. Additionally, we developed a UV-based method for determining methacrylic acid in GelMA and demonstrated how methacrylic acid contamination affects the quantification of methacrylic groups. Rather than reporting the degree of substitution alone, we define the methacrylic content as the quantity of methacrylic groups per 100 kDa gelatin unit, which makes the metric independent of the number of lysine residues in gelatin. This routine-ready approach lowers the barrier to reliable GelMA characterization and standardizes reporting across batches and laboratories.

Multivalent interactions mediated by multidomain proteins are pivotal in numerous biological processes. However, the thermodynamic intricacies of the domain interactions within such complexes remain elusive. In this study, we employed surface plasmon resonance to explore the temperature-dependent kinetics of multidomain protein interactions across various valences from monomers to tetramers. Rigorous screening of protein-peptide binding pairs fused with discrete multivalent protein scaffolds facilitated the selection of candidates with minimal nonspecific interactions and suitable monomer binding kinetics that could be extended to higher valences. We developed a theoretical model to extract the thermodynamic quantities for both inter- and intramolecular interactions. By employing initial rate analysis, we could extract thermodynamic quantities describing complicated interactions between multivalent proteins. Our analysis provides novel insights into the thermodynamics of intramolecular interactions in multivalent protein complexes with implications for protein design and engineering.

Creating multifunctional hydrogel scaffolds that combine gradient conductivity with patterned morphologies to mimic the extracellular matrix and modulate neuronal behavior remains challenging. This study developed a conductive, morphology-gradient hydrogel using an electrophoresis-based strategy. A thermosensitive polyisocyanopeptide (PIC) hydrogel served as the matrix, while graphene oxide nanosheets (GO) migrated under an electric field, forming a continuous gradient. This gradient enabled spatially varying conductivity, microstructure, and fiber alignment. Adjusting field strength and electrode configuration allowed precise control over GO distribution and patterned morphologies. SH-SY5Y cells aligned along the gradient, with higher GO regions promoting greater cell circularity and smaller cell areas than low-GO regions and controls. This work provides new insights into designing programmable multigradient conductive hydrogels, holding strong potential for advancing neural tissue engineering.

Spray-dried TEMPO-oxidized cellulose nanofiber (TOCN)-Fe₃O₄ (TF) composite particles were fabricated using TOCNs of distinct fiber lengths, where the long TOCNs were approximately 3 times longer (around 1 μm) than the short TOCNs (approximately 350 nm). The objective was to elucidate how nanofiber aspect ratio governs particle morphology, magnetic performance, and bioaffinity. SEM and TEM analyses revealed that both TOCN types formed spherical particles (approximately 2-3 μm) with fibrous surface textures, yet the Fe₃O₄ distribution varied significantly. Short TOCNs promoted dense fiber entanglement within droplets, effectively entrapping Fe₃O₄ nanoparticles inside the particle core, whereas long TOCNs facilitated Fe₃O₄ migration toward the particle surface. Despite similar ζ-potentials (-44 to -49 mV) and superparamagnetic hysteresis behavior, surface Fe₃O₄ accessibility strongly influenced biofunctional response without altering magnetization. These findings provide a scalable strategy for designing bioactive magnetic cellulose composites with customizable surface reactivity for biosensing, biocatalysis, and magnetic separation in biomedical field.

The poor compatibility and low degree of substitution of lignin severely limit its application as a polyol substitute in polyurethane elastomers. Herein, by regulating the molecular weight of lignin, high-content and uniform bonding of lignin in polyurethane (PU) has been achieved. Even at a substitution degree of 15%, lignin can still be fully integrated into the macromolecular chains of PU, resulting in a 27% increase in tensile strength and a 124% increase in elongation at break of the elastomer, respectively. Furthermore, a remarkable enhancement of over 165% in the tensile strength of the elastomer has been realized through adjusting the molecular weight of lignin. And through life cycle assessment, the importance of using lignin as a substitute for polyols has been confirmed. Notably, the thermal stability and surface hydrophobicity of the elastomer have also been significantly improved, and it can be combined with MXene to fabricate composite devices with sensitive strain responsiveness. This promising advancement is expected to promote the green and sustainable development of PU and its application in multifunctional wearable devices.

Elastin-like polypeptides (ELPs) are promising drug delivery vehicles, yet their bioactivities remain underexplored, likely due to the lack of applicable protein delivery systems. To address this, here, a fusion protein ELP19 (19.5 kDa) and a β-glucan nanogel (for short, BGNG) system were designed and constructed. The BGNGs formed using dual phenylboronic acid (PBA)-functionalized poly(ethylene glycol) as a cross-linker through a reverse microemulsion method were utilized to individually load two different ELP variants (another ELP with a molecular weight of 17.035 kDa, termed as ELP17) for intracellular delivery and bioactivity investigation. The synthesized BGNGs with a size of 77.9 nm exhibit excellent protein-loading and delivery capabilities, and the developed BGNG/ELP complexes retain excellent colloidal stability and cytocompatibility. In vitro studies reveal that the BGNG-mediated intracellular delivery of ELP19 significantly promotes macrophage polarization toward the M2 phenotype, whereas the delivery of ELP17 shows no such effect. In addition, the BGNG/ELP19 complexes are able to maturate dendritic cells to generate immunogenicity, while BGNG/ELP17 complexes do not have such immunogenicity. These findings highlight the functional divergence between the two different ELP variants and underscore the potential of BGNGs as a protein carrier and ELP19 as a modulator of macrophages, providing a reference for the future biomedical application of BGNG-based nanoplatforms and ELP-based therapeutics.

As a ubiquitous iron-storage protein, human heavy chain ferritin (FTH) is widely used in drug delivery. Recent advances in FTH engineering highlight the therapeutic and translational potential of glycosylation. We herein report the biosynthesis of various glycosylated FTHs (Glc-FTH, Glc_n-FTH, and Gal-Glc-FTH) in Escherichia coli via enzymatic methods. Their self-assembly and thermal stability are unaffected by glycosylation, while the acid sensitivity is significantly enhanced, enabling depolymerization in a milder and more controllable manner. Gal-Glc-FTH exhibits exceptional advantages (low cytotoxicity, low immunogenicity, minimal apoptosis-inducing ability, prolonged half-life, and strong hepatic targeting), which collectively enhance its applications in hepatic targeted drug delivery. Although Glc_n-FTH also significantly enhances hepatic targeting, its induction of high-titer antibodies indicates that it is more suitable for development as a vaccine carrier. Our findings emphasize the critical role of glycans in FTH properties, providing novel strategies and insights for cancer-targeted drug delivery systems.