ACS Applied Bio Materials最新文献

Since the advent of clustering triggered emission (CTE), its potential for bioimaging has remained relatively unexplored, especially in the context of polyhydroxyurethanes (PHUs), despite their simple, non-isocyanate synthetic methodology and inherent biocompatibility. Building on these insights, we report facile, one-pot synthesis of a range of polyhydroxyurethanes (PHUs) using a careful selection of diamines to provide the necessary solubility in aqueous media for cell imaging applications. The synthesized PHUs exhibit an increase in CTE emission upon thermal annealing, with an almost sixfold increase in emission intensity on increasing the annealing time from 0 to 48 h at 90 °C. Furthermore, the concentration-dependent fluorescence studies in aqueous media show an approximately 8-fold increase in emission intensity as the polymer concentration increases from 1 to 20 mg/mL. Moreover, the excellent cytocompatibility of these PHUs against human embryonic kidney (HEK-293) and human breast adenocarcinoma (MDA-MB-231) cell lines, coupled with CTE and water solubility, enabled the imaging of living cells and deep penetration into 3D tumor spheroids. Overall, in this study, we emphasized a simple, eco-friendly, and cost-effective approach to develop biocompatible fluorescent PHUs for cellular and 3D tumor imaging.

Chronic diabetic wounds remain difficult to heal because of persistent oxidative stress, chronic inflammation, impaired angiogenesis, and dysfunctional extracellular matrix remodeling. Developing biofabricated living scaffolds that combine structural support with active microenvironment regulation remains challenging. Herein, we engineered a photocrosslinkable methacrylated recombinant type I collagen bioink (RCIMA) and fabricated a biomimetic bilayer cell-laden scaffold (RCIMA-Cell) using digital light processing (DLP) bioprinting. Owing to the excellent physiological processability of recombinant collagen, RCIMA exhibited rapid photocuring, enhanced swelling behavior, improved enzymatic stability, and superior mechanical performance. The bilayer scaffold spatially integrated keratinocytes (HaCaT) and fibroblasts (HFF-1) to mimic the hierarchical architecture of native skin. In vitro, RCIMA promoted the migration, proliferation, and differentiation of both cell types while maintaining high post-printing viability. In diabetic wounds, RCIMA-Cell accelerated wound closure, promoted collagen remodeling, reduced ROS accumulation, induced M2 macrophage polarization, and enhanced angiogenesis and vascular maturation, offering a versatile strategy for regenerative wound repair.

The transition of metal-organic framework and polymer from random assembly to ordered spatial organization in enzymatic tandem systems is critical for enhancing cascade catalytic performance. Herein, thermo-responsive poly(styrene-co-maleic anhydride)-block-poly(N-isopropylacrylamide) (PSMN) was designed and employed to integrate UiO-66-NH2 (U) with glucose oxidase and horseradish peroxidase (GOx/HRP), constructing orderly-assembled U@PSMN@GOx/HRP, random assembled Up-PSMN@GOx/HRP and PSMN@GOx/HRP enzyme reactors with spatial confinement. The thermo-responsive conformational transition of flexible PSMN, together with the structural restriction imposed by covalently integrated rigid U, cooperatively established a more ordered spatial confinement space around GOx/HRP. At 37 °C, the Kcat value of U@PSMN@GOx/HRP was 83.2-fold higher than that at 15 °C, while, 155.5- and 130.1-fold higher than those values of PSMN@GOx/HRP and UP-PSMN@GOx/HRP, respectively. The enhanced cascade catalysis was further translated into sensitive glucose detection, affording a broad linear range of 2.0-1200.0 μM and a detection limit of 0.67 μM, together with reliable analytical performance in orange fruits. This study provides strategy for coupling stimuli-responsive polymer yielded confined space with orderly-assembled MOFs@polymer@enzyme induced confinement to enhance enzymatic cascade catalysis.

Controlled delivery of anti-inflammatory agents using bioactive nanomaterials offers a strategy to achieve localized and temporally regulated modulation of inflammatory and neurogenic signaling. Here, we engineered an adsorption-based chitosan nanoparticle platform for controlled Ibuprofen delivery to coordinate inflammatory and neurogenic responses during the acute postoperative phase. The formulation was designed to generate an initial burst release followed by sustained drug delivery while leveraging the intrinsic immunomodulatory properties of chitosan. Therapeutic performance was evaluated using a previously established human three-dimensional tri-culture microfluidic platform (3TMP) that recreates the periodontal ligament neuroimmune microenvironment under lipopolysaccharide (LPS)-induced inflammatory conditions. The engineered platform exhibited a two-phase release profile characterized by an initial burst followed by a plateau that translated into coordinated suppression of interconnected inflammatory and neuronal pathways, including the reduction of pro-inflammatory cytokines, prostaglandin E2 (PGE2), calcitonin gene-related peptide (CGRP), and the nociceptive ion channels TRPV1 and TRPA1. In comparison, free Ibuprofen only partially reduced TNF-α, IL-6, and IL-8 and failed to suppress IL-1β, PGE2, TRPV1, or TRPA1. These findings demonstrate how controlled-release biomaterial design governs therapeutic performance by coordinating interconnected neuroimmune pathways. Furthermore, this work establishes human microphysiological systems as robust platforms for evaluating structure-function relationships in bioactive nanotherapeutic systems for periodontal inflammation.

Theaflavins (TFs), the major bioactive polyphenols in black tea, possess potent antioxidant and anti-tyrosinase activities, but their practical application is severely limited by poor chemical stability and low bioavailability. To overcome these drawbacks, we engineered zein/cyclodextrin composite nanoparticles to enhance the stability and bioactivity of TFs. Among three cyclodextrins including β-cyclodextrin (β-CD), γ-cyclodextrin (γ-CD), and hydroxypropyl-β-cyclodextrin (HP-β-CD), the Zein/HP-β-CD formulation was optimal, yielding a particle size of 137 nm, a polydispersity index as low as 0.06, an encapsulation efficiency of 96.7%, and robust colloidal stability under various pH, temperature, and ionic strength conditions. Structural analyses confirmed the formation of spherical amorphous nanocomposites stabilized by hydrogen bonding and hydrophobic interactions. Compared with free TFs, Zein/HP-β-CD@TFs nanoparticles exhibited superior antioxidant activity with a DPPH radical scavenging rate of 79.5% and a 3-fold lower IC50 for tyrosinase inhibition. In ultraviolet (UV) B-irradiated HaCaT cells, the nanoencapsulated TFs increased cell viability from 64.1% to 87.7%. In a zebrafish whitening model, the nanoparticles achieved 35.0% melanin inhibition at a total mass concentration of 0.025%, which was 1.4-fold higher than that of free TFs at the same concentration, while also exhibiting a 4-fold higher safety margin with a maximum tolerated concentration of 0.1% compared with 0.025% for free TFs. These findings demonstrate that Zein/HP-β-CD nanoparticles serve as an effective delivery platform by establishing a structure-activity relationship linking molecular interactions to enhanced bioactivity, improving the stability, bioavailability, and health-promoting functions of TFs for cosmetic and nutraceutical applications.

Recently, the growth of two-dimensional (2D) materials has opened innovative paths in nanobiotechnology, and MXenes have emerged as leading candidates owing to their superior physicochemical performance and functional adaptability. MXenes, a family of transition metal carbides, nitrides, and carbonitrides, reveal excellent electrical conductivity, large surface area, tuneable surface chemistry, hydrophilicity, and exceptional biocompatibility. These unique features make them highly attractive for biosensing and bioimaging applications. This review systematically abridges the recent advancements in MXene and its composites for biosensor development, containing electrochemical, optical, wearable, and flexible biosensors for the revealing of biomolecules, pathogens, cancer biomarkers, and glucose. The role of surface functionalization, hybridization with polymers, metal nanoparticles, carbon-based nanomaterials, and biomolecules in enhancing sensitivity, selectivity, and stability is critically deliberated. Moreover, the application of MXene composites in bioimaging approaches such as fluorescence imaging, photoacoustic imaging, magnetic resonance imaging (MRI), and multimodal imaging is explored, emphasizing their photothermal conversion efficiency and contrast development competences. Various challenges associated with long-term stability, oxidation resistance, toxicity, and large-scale production were also addressed, along with future perspectives for clinical translation and next-generation smart biomedical platforms. Overall, MXene-based materials clamp significant potential to transform biosensing and bioimaging techniques via multifunctional and integrated diagnostic systems.

Green-fluorescent carbon quantum dots (CQDs) were hydrothermally synthesized from the Mongolian medicine Harigabri, exhibiting uniform size (∼2.5 nm) and strong emission at 521 nm under 468 nm excitation. Based on the fluorescence resonance energy transfer (FRET) between the CQDs (donors) and AgNPs (acceptors), an aptamer-functionalized biosensor (Apt-CQDs/AgNPs) was constructed for selective Escherichia coli detection. Target recognition by the aptamer inhibited FRET and restored fluorescence. The sensor showed a linear response from 9 × 102 to 9 × 107 CFU/mL with a detection limit of 5 CFU/mL. This work highlights Harigabri-derived CQDs as promising nanomaterials for rapid pathogen detection and demonstrates the potential of traditional medicinal resources in biosensing applications.

The escalating crisis of antibiotic resistance and biofilm-associated infections urgently demands therapeutic strategies with distinct mechanisms of action. Antibacterial photodynamic therapy (abPDT) offers a promising alternative, yet its clinical translation is often limited by the poor solubility, low biocompatibility, or complex delivery requirements of conventional photosensitizers (PSs). Here, we report the application of recombinant water-soluble chlorophyll proteins (WSCPs) from the Brassicaceae family as fully natural, self-contained PSs for abPDT. WSCP forms exceptionally stable tetrameric complexes with chlorophylls, providing outstanding water solubility, high photostability, negligible dark toxicity, and food-grade biocompatibility. Upon 660 nm light irradiation, WSCP-mediated abPDT achieves broad-spectrum killing of clinically relevant Gram-positive (including methicillin-resistant Staphylococcus aureus, MRSA) and Gram-negative bacteria and effectively disrupts mature biofilms. Mechanistically, WSCP adheres to bacterial surfaces and generates singlet oxygen in situ, causing rapid membrane permeabilization, leakage of intracellular contents, and cell death, through a resistance-evading, physical mode of action. In a murine MRSA-infected wound model, a single topical application of WSCP followed by light exposure significantly reduces bacterial burden, suppresses inflammation, accelerates tissue regeneration, and promotes wound closure without observable toxicity. This work establishes WSCP-based abPDT as a safe, simple, and highly effective platform to combat antibiotic-resistant and biofilm-associated infections.

Effective wound-fluid management is essential in medical applications, as dressings must absorb, retain, and regulate excess blood, exudate, and other biological fluids. Gelatin-hyaluronic acid (Gel/HA) hydrogels are promising dressing materials because they provide a hydrated, tissue-mimetic environment and combine the biological functions of both polymers. Their performance depends strongly on the crosslinking strategy, which regulates network architecture, fluid transport, and mechanical integrity. Three Gel/HA networks were prepared by physical association (Network I), glutaraldehyde-mediated covalent crosslinking (Network II), and PEGDA-mediated interpenetrating-network formation (Network III). Molecular interactions, morphology, fluid uptake, and mechanical properties were evaluated within a structure-transport-function framework. The networks exhibited distinct pore structures, with average pore sizes of 21 ± 7, 2.3 ± 0.8, and 9 ± 3 μm and porosities of 74 ± 3, 59 ± 3, and 67 ± 3% for Networks I-III, respectively. Tensile strength increased from 62 ± 5 kPa for Network I to 127 ± 7 kPa for Network II and 215 ± 9 kPa for Network III, while elongation at break increased from 152 ± 9 to 257 ± 12 and 343 ± 14%, respectively. Simulated blood uptake at 240 min reached 483 ± 45, 842 ± 59, and 1285 ± 72% for Networks I-III, respectively. An integrated hydrogel performance index was used as a comparative dimensionless descriptor of selected transport and mechanical properties. Overall, the results show that network formulation yields distinct combinations of pore architecture, fluid transport, and mechanical performance, providing a basis for comparing Gel/HA hydrogel designs for wound management applications that balance fluid management and mechanical properties.

Dentin is the primary mineralized tissue of the tooth, essential for pulp protection and enamel support. Its regenerative capacity is critical for dental health. This review summarizes recent progress in odontogenic regeneration, covering fundamental biological mechanisms and translational applications. A literature search of peer-reviewed studies on odontogenic regeneration, dental tissue engineering, and biomaterial-based strategies was conducted. Key advances include signaling pathway-guided stem cell differentiation into functional odontoblasts, which promotes reparative dentin matrix formation, and biomaterial innovations that provide optimized cellular microenvironments. Emerging clinical strategies, including 3D printing, growth factor delivery systems, and gene-editing approaches, are also discussed. Despite substantial progress, challenges remain in the precise control of stem cell fate specification, long-term biocompatibility of biomaterials, and high clinical costs. Future interdisciplinary integration holds promise for overcoming these hurdles, advancing personalized therapies, and expanding dental restoration and regenerative medicine. The evolving strategies offer meaningful potential for dentin-pulp complex regeneration, improved pulp preservation, personalized scaffold fabrication via 3D printing, and the eventual development of cost-effective, biocompatible clinical therapies.