Colloids and Surfaces B: Biointerfaces最新文献

Diabetic wound healing poses a significant clinical challenge, primarily due to bacterial infection and persistent inflammation mediated by excessive reactive oxygen species (ROS). To address this issue, we developed a nanocomposite named Carbon quantum dot-chlorogenic acid (CD-C), which integrates synergistic antibacterial and antioxidant functionalities to promote diabetic wound healing. CD were synthesized via a facile method using cost-effective precursors, citric acid and urea, and subsequently combined with chlorogenic acid to form a nanocomposite system capable of simultaneous photothermal sterilization and ROS scavenging. The as-prepared CD exhibited a particle size distribution of 2-10 nm, while CD-C showed an average size between 150 and 250 nm. Furthermore, CD-C demonstrated remarkable photothermal performance, with an impressive conversion efficiency of 40.65 %. At a concentration of 150 μg/mL, CD-C displayed broad-spectrum antibacterial activity against two typical drug-resistant bacterial strains, achieving an inhibition rate exceeding 98 %. It also effectively disrupted bacterial biofilms. Concurrently, CD-C efficiently scavenged ROS, mitigating oxidative stress-induced cellular damage. To enhance its applicability, CD-C was incorporated into a silk fibroin (SF) hydrogel, forming a CD-C@SF composite dressing. This system significantly accelerated diabetic wound healing through combined antibacterial, antioxidant, and anti-inflammatory effects. Animal experiments revealed that nearly complete wound closure was achieved within 10 days following treatment with CD-C@SF. This study not only highlights the promise of integrated nanomaterial platforms for diabetic wound management but also underscores the potential of carbon quantum dot-based composites as an effective biomedical strategy.

Gallic acid (GA), recognized for its antioxidant and anti-inflammatory bioactivities, has demonstrated efficacy in ameliorating experimental colitis. However, its clinical translation is impeded by poor water solubility. Deep eutectic solvents (DESs), as environmentally friendly green solvent systems, have emerged as promising candidates to address this limitation. Hydrogels are considered a viable strategy to enhance the anti-colitis efficacy of GA. The hydrogel (PC-CuGA) was fabricated using a one-step mixing method and cross-linked through non-covalent interactions by DES, polyvinyl alcohol (PVA), chitosan (CS), GA, and Cu^2 + . Additionally, DSS-evoked colitis was established and applied to clarify the regulatory efficacy of PC-CuGA on intestinal barrier impairment, inflammatory response, and redox imbalance. Results revealed that PC-CuGA exhibited a robust gel state with excellent temporal stability, superior storage modulus, enhanced structural integrity, and favorable biosafety. In the colitis model, PC-CuGA intervention effectively mitigated DSS-induced pathology, as evidenced by reduced weight loss, attenuated colon shortening, and lowered disease activity index (DAI) scores. Histopathological analysis further demonstrated that PC-CuGA preserved intestinal barrier integrity and protected tight junction proteins. Mechanistically, PC-CuGA significantly dampened the activation of the TLR4/MyD88/NF-κB axis and downregulated the expression of pro-inflammatory cytokine genes, while upregulating the expression of anti-inflammatory cytokines. Collectively, these findings elucidate that the protective effects of PC-CuGA against experimental colitis associated with reinforcing intestinal barriers, suppressing oxidative stress, and excessive inflammation. This work provides a novel therapeutic strategy for the prevention and management of colitis, highlighting the potential of DES-based hydrogels in enhancing the bioavailability and efficacy of bioactive compounds.

Bovine mastitis caused by Staphylococcus aureus represents a major economic and health challenge in the dairy industry due to the pathogen's virulence factors and biofilm-forming ability, which confer resistance to conventional antibiotics. Sustainable alternatives are therefore urgently needed in the context of rising antimicrobial resistance. This study evaluated the chemical composition, surface interaction properties, and antivirulence potential of an extracellular polymeric substance (EPS-H21) produced by commensal Bacillus sp. strain H21, previously isolated from the microbiota of healthy bovine mammary glands and shown to antagonize mastitis-causing S. aureus. Spectroscopic analyses demonstrated that EPS-H21 mainly consists of heteropolysaccharides enriched in N-acetylglucosamine (GlcNAc) and other aldoses, and protein with minor aliphatic components. The biomaterial exhibited high thermal stability (>250 °C), and both amorphous and crystalline domains, as confirmed by differential scanning calorimetry and solid-state ¹ ³C nuclear magnetic resonance (NMR) spectroscopy. Results suggest that EPS-H21 acts as a supramolecular assembly with relevant interfacial activity. Functionally, EPS-H21 inhibited biofilm formation, disrupted mature biofilms, reduced adhesion and internalization of S. aureus into bovine mammary epithelial cells (MAC-T), and impaired intracellular persistence, all without affecting bacterial viability or host cell integrity. Overall, the structural stability and multifunctional biological activity of EPS-H21 highlight its potential as a microbiota-derived biomaterial for developing non-antibiotic therapies or preventive strategies against S. aureus mastitis.

Localized chemotherapy is hampered by rapid clearance, systemic toxicity, and poor tumor retention, motivating depots that maintain site-specific exposure. We introduce a hierarchical nanocapsule-in-hydrogel platform built from chitosan conjugated to Pluronic F127 derivatives for co-delivery of doxorubicin (DOX) and gallium nitrate (Ga(NO₃)₃). Succinic-acid-modified F127-chitosan (SAF-C) self-assembles into ∼34 nm nanocapsules, while alanine-modified F127-chitosan (ADF-C) forms an injectable, thermogelling network via covalent crosslinking. Embedding SAF-C within ADF-C yields a dual-responsive depot that suppresses burst release and enables staged, pH- and temperature-sensitive delivery: proton-labile coordination accelerates Ga³ ⁺ release, whereas DOX follows diffusion-limited kinetics, extending liberation from hours to days. Both carriers show high in-vitro biocompatibility (>90 % viability in NIH-3T3, HeLa, and 4T1). In 4T1 triple-negative breast cancer cells, the depot sustains apoptotic signaling and reduces viability to < 10 %, while free DOX or Ga³ ⁺ cause transient necrosis with partial recovery. Fluorescence imaging reveals delayed yet enhanced nuclear DOX accumulation and intracellular Ga³ ⁺ retention, indicating spatiotemporal synergy between gallium's metabolic interference and DOX-mediated DNA damage. By biasing cell death toward apoptosis over necrosis, this nanocapsule-in-hydrogel platform offers a generalizable design principle for localized multi-agent delivery.

Hepatic fibrosis, a prevalent pathological process in chronic liver diseases, represents a significant global public health challenge due to its progression toward severe conditions such as cirrhosis and hepatocellular carcinoma. Despite extensive research efforts, no specific anti-fibrotic agents have been approved for clinical use, underscoring the urgent need for innovative therapeutic strategies. Activated hepatic stellate cells (HSCs) excessively produce extracellular matrix (ECM) components like collagen, deteriorating fibrosis progression. HSCs, storing lipid-soluble vitamin A, are a promising target for hepatic fibrosis. Herein, a novel theranostic platform based on vitamin A-modified melanin nanoparticles (MNP-VA) is constructed for the integrated diagnosis and treatment of hepatic fibrosis. Thanks to the superior near-infrared (NIR) absorption and thermal stability properties of melanin, the MNP-VA nanoparticles perform therapeutic intervention and real-time monitoring via low-temperature photothermal therapy (LT-PTT) guided by accurate photoacoustic imaging (PA). PA uses the photoacoustic effect for high-resolution, deep-tissue imaging. PTT converts laser light into heat to precisely target and destroy diseased cells with minimal side effects. LT-PTT further reduces damage to healthy tissues while maintaining treatment efficacy. This platform, combined with melanin's antioxidant properties and NIR irradiation, leverages the targeting specificity of vitamin A toward HSCs, significantly reducing collagen deposition and restoring liver architecture in animal models. Overall, our findings indicate that MNP-VA offers a robust strategy for the theranostic management of hepatic fibrosis, addressing the limitations of conventional therapies and paving the way for future clinical translation.

Luteolin (LUT), a promising phytochemical for atopic dermatitis (AD) therapy, is limited by poor solubility and skin permeability in topical application. To address this, a novel LUT-loaded microemulsion-based (LUT-ME) gel was developed to facilitate drug delivery. The optimal LUT-ME formulation, obtained by a pseudo-ternary phase diagram and D-optimal mixture design, comprised 7.23 % glycerol triacetate, 34.56 % Smix, and 58.21 % water. DLS analysis showed a mean droplet size of 28.77 ± 0.31 nm and a PDI of 0.31 ± 0.04, while the zeta potential was -2.95 ± 0.68 mV and the drug loading reached 7.28 ± 0.05 mg/mL. Characterization by TEM, XRD, and FTIR demonstrated uniform droplet morphology, amorphous LUT dispersion, and good drug-excipient chemical compatibility. Notably, LUT-ME more significantly suppressed reactive oxygen species (ROS) and pro-inflammatory mediators in LPS-stimulated RAW264.7 cells compared to free LUT. Incorporation of sodium hyaluronate (SH) yielded a shear-thinning gel with favorable spreadability, good stability, and negligible skin irritation. Moreover, enhanced skin permeation of LUT-ME gel (2.09-fold vs LUT gel) in ex vivo studies contributed to its superior anti-inflammatory and histopathological effects in an AD mouse model. These results indicate that LUT-ME gel markedly improves the topical therapeutic efficacy of LUT against AD.

In this work, we report a green and surfactant-free biosynthesis of gold nanotriangles (AuNTs) using gelatin as a multifunctional stabilizing and biocompatible capping agent. Gelatin effectively mediated particle growth in the presence of ascorbic acid, enabling precise tuning of the longitudinal localized surface plasmon resonance (LSPR) of AuNTs between 880 and 1090 nm through control of size and morphology. The resulting LSPR within the NIR-II plasmonic window provides distinct therapeutic advantages, including deeper tissue penetration, reduced light scattering, and diminished tissue autofluorescence, highly relevant for clinical translation. Here, we present a systematic evaluation of the thermoplasmonic performance of biosynthesized AuNTs under low-cost LED irradiation across the visible and NIR biological windows, yielding photothermal conversion efficiencies of up to ∼65 % in the NIR range. Comparable thermoplasmonic responses were obtained under two laser sources (532 nm and 980 nm), therefore demonstrating the efficiency of LED as irradiation sources for NIR responsive AuNTs. In vitro investigations demonstrated negligible intrinsic cytotoxicity of gelatin-stabilized AuNTs and confirmed the cellular uptake in two breast cancer lines (i.e., MDA-MB-231 and MCF-7). Upon irradiation, distinct cell-type-dependent responses were observed, with significant photothermal cytotoxicity (47 %) induced particularly in MCF-7 cells under 850 nm exposure. Taken together, these results establish gelatin-biosynthesized AuNTs as efficient, biocompatible light-to-heat nanotransducers and highlight the potential of LED-driven photothermal therapy across the visible and NIR spectral regions.

Oral cancer poses a serious disease as it has the highest incidence, and surgical intervention leads to maxillofacial deformation (facial, dental, and jaw disfigurement). Thus, developing efficient therapy is essential. Herein, Bortezomib (BTZ), a proteasomal inhibitor primarily used clinically for the treatment of hematologic cancers, is equally effective in solid tumors and has been explored via a nanomedicine strategy. A graphene oxide-based unique nanoplatform was developed and coated with Tannic Acid (TA) to enhance its dispersibility, achieve superior drug loading via non-covalent binding interactions, including hydrogen bonding and electrostatic interactions, with bortezomib, and improve its anticancer therapeutic response. The developed BTZ@GOT scaffolds formed stable nanoparticles with a size of 142.3 nm, a zeta potential of -2.31 mV, and a BTZ loading of 14.2 %, where the TA coating assisted in the conversion of the sheet-like structure to uniformly dispersed particles. These BTZ@GOT NPs were stable, least hemolytic, and demonstrated targeted release in a low pH environment. Interestingly, BTZ@GOT NPs demonstrated enhanced photothermal efficiency, raising the temperature to 50 ºC. The in vitro therapeutic efficacy study, performed on murine and human oral carcinoma cell lines, MOC2 and FaDu, respectively, demonstrated enhanced accumulation in cells over time, as well as the accumulation of pro-apoptotic factors and reactive oxygen species, leading to mitochondrial damage and ultimately resulting in cancer cell death. Moreover, in vivo studies in MOC2-induced tumor-bearing mice demonstrated a significant upregulation of ER stress markers, including PERK and PDI, as well as remodeling of macrophages, characterized by the upregulation of M1 markers, such as iNOS, TNF-α, and CD86. Thus, BTZ@GOT is an efficient nanotherapy that warrants further exploration for the treatment of oral carcinoma.