Colloids and Surfaces B: Biointerfaces最新文献

The misuse of antibiotics has led to the growing problem of multidrug-resistant (MDR) bacteria, and there is still a lack of effective antibacterial agents that can replace antibiotics. Therefore, the design and development of multifunctional nanomaterials with long-term inhibitory effects on drug-resistant bacteria are extremely challenging. In this study, a multifunctional biomimetic self-assembly system, BSA-ZnO&Quercetin, based on bovine serum albumin (BSA), ZnO, and quercetin, was established using a simple and controllable method. The prepared self-assembly system has high stability and biocompatibility, and could fully combine the performance advantages of each component. BSA-ZnO&Quercetin showed excellent broad-spectrum antibacterial activity without inducing bacterial resistance. The related antibacterial mechanism of BSA-ZnO&Quercetin primarily involves biofilm inhibition and destruction, and inducing the production of reactive oxygen species, resulting in the death of the bacteria. The biomimetic self-assembly system BSA-ZnO&Quercetin constructed in this research is expected to replace antibiotics for antibacterial application.

Several anions present in the extracellular matrix (ECM) not only have significant physiological functions in ECM but also play an important role in regulating peptide-based self-assembly. Herein, we have employed a non-conventional approach to overcome the limitations of the positively charged Cardin-motif peptide that failed to self-assemble at physiological pH. We used a simple and elegant strategy by employing different anions such as HPO₄^2-, Cl^- and I^- to mask the overall surface charge of peptide. Interestingly, these anions were utilized to modulate the nanostructure formation and mechanical stiffness of peptide hydrogels owing to their differential interactions with water molecules according to the Hofmeister series. Interestingly, these anions induced hydrogels showed diverse cellular responses on two different cell lines, fibroblast and neuronal, indicating diverse application potential of the new scaffold. Thus, this study emphasizes the importance of anions to regulate the self-assembly of Cardin-motif peptide and this approach can be utilized in developing the ideal biomimetic model of ECM for futuristic applications.

Landfill leachate, a complex mixture of pollutants, poses a significant environmental hazard. This study reports the synthesis and characterization of superabsorbent nanocomposites (SANs) designed for enhanced performance in waste management applications. SANs were prepared using carboxymethyl cellulose (CMC) and sodium polyacrylate (SPA) as the main components, carbon dots (CDs) to improve absorption, and Satureja Khuzestanica essential oil (SEO) for antibacterial performance. The results demonstrated that the addition of CDs significantly increased the absorption capacity and liquid retention of the samples, with a water absorption capacity reaching up to 8621 %. Furthermore, the samples exhibited high mechanical strength, with tensile strength improving by over 100 % in the presence of CDs. The inclusion of SEO provided strong antibacterial activity against Escherichia coli and Staphylococcus aureus, with inhibition zones measuring up to 26 mm. These SANs, with their high absorption capacity, mechanical robustness, and antibacterial properties, show great potential for improving waste management practices, particularly in leachate absorption strategies.

Wound healing is delayed due to the infection and biofilm formation of antibiotic-resistant species of gram-negative bacteria especially Pseudomonas aeruginosa and Escherichia coli. Antibacterial photodynamic therapy provides an efficient therapeutic strategy for overcoming drug resistance by producing reactive oxygen species (ROS) and reactive nitrogen species (RNS). Here, we have designed a low-cost light emitting diode (LED) based reusable and non-invasive titanium dioxide nanoparticles patch which is sandwiched between the thin polymer layers. The light-induced pore formation in the polymeric film due to the free radical, in turn, passes through the system and kills the bacteria rather than nanoparticles entering the system resulting in the reusability nature of the patch. The patch's in vitro antibacterial and antibiofilm activity and their mechanism (synergic ROS-induced RNS) were studied. In addition, the reusable antibacterial properties, biocompatibility and wound-healing properties of the patch were also successfully elucidated.

Two-photon photodynamic therapy (TP-PDT) offers an innovative approach to cancer treatment that utilizes near-infrared light to activate photosensitizers and generate reactive oxygen species (ROS) for targeted cancer cell elimination. TiO₂-CUR-Sofast (TCS), which uses TiO₂ nanoparticles and Sofast cationic polymer to modify curcumin (CUR), has demonstrated potential as a photosensitizer under visible light irradiation, addressing the limitations of CUR's narrow spectral range and low bioavailability. This study explores the utility of the two-photon technique to activate TCS within the infrared spectrum, aiming to enhance ROS production and penetration depth compared to traditional CUR. TCS exhibits a significantly higher ROS production at 900 nm excitation wavelength, approximately 6-7 times that of CUR, signifying a substantial increase in efficiency. In TP-PDT, TCS showed significant phototoxicity against HeLa and T24 cell lines compared to CUR. Furthermore, TCS's photodynamic efficacy is further confirmed by cell apoptosis and necrosis studies, where approximately 89 % of cells treated with TCS under 900 nm light irradiation were observed in an apoptosis/necrosis state. And the TP-PDT effect in deep tissue was simulated using pig skin. It shows that the two-photon excitation has a significant penetration depth advantage over the single-photon excitation. These results indicate that the two-photon PDT scheme of TCS has greater potential than the single-photon PDT scheme in the treatment of cancer, and provides an experimental foundation for the effective treatment of deep lesions.

In this study, we developed the ginger vesicles as nanocarrier for the targeted delivery of 10-hydroxy-camptothecin (HCPT), aiming to improve its therapeutic efficacy while minimizing the systemic toxicity. Ginger vesicles exhibit a wide spectrum of biological activities and excellent biocompatibility, rendering them as the promising nanocarriers candidates for anticancer drug delivery. The ginger vesicles with an average diameter of 86.83 nm were successfully prepared by utilizing a gradient centrifugation method. The loading conditions for HCPT into the ginger vesicles were optimized through the addition of an appropriate amount of Ca²⁺. The loading efficiency, size distribution, stability, and cytotoxicity profile of the ginger vesicles were comprehensively characterized using UV spectroscopy, transmission electron microscopy (TEM), dynamic light scattering (DLS), and cytotoxicity experiments. Furthermore, in vitro cytotoxicity studies confirmed that ginger vesicles loaded with HCPT exhibited high inhibitory activity against tumor cells as evidenced by fluorescence imaging and flow cytometry analysis. Most importantly, in vivo antitumor assay demonstrated that the ginger vesicles loaded with HCPT displayed remarkable inhibitory effects on tumor growth. In summary, our results demonstrated the potential application of the ginger vesicles as ideal nanocarriers for delivering HCPT.

The rational design of nanozymes with highly efficient reactive oxygen species (ROS) generation to overcome the resistant infection microenvironment still faces a significant challenge. Herein, the highly active Fe single-atom nanozymes (Fe SAzymes) with a hierarchically porous nanostructure were prepared through a colloidal silica-induced template method. The proposed Fe SAzymes with satisfactory oxidase (OD)-like and peroxidase (POD)-like activity can transform O₂ and H₂O₂ to superoxide anion free radical (•O₂^-) and hydroxyl radical (•OH), which possess an excellent bactericidal effect. Also, the glutathione peroxidase (GPX)-like activity of Fe SAzymes can consume glutathione in the infection microenvironment, thus facilitating ROS generation to enhance the sterilization effect. Besides, the intrinsic photothermal effect of Fe SAzymes further significantly boosts the enzyme-like activity to generate much more reactive oxygen species for efficient antibacterial therapy. Accordingly, both in vitro and in vivo results indicate that the Fe SAzymes with synergistically photothermal-catalytic performances exhibit satisfactory antibacterial effects and biocompatibility. This work provides new insights into designing highly efficient SAzymes for effective sterilization applications by an amount of ROS generation.

Pulmonary embolism remains the third leading cause of human mortality after malignant tumors and myocardial infarction. Commonly available thrombolytic therapeutic agents suffer from the limitations of very short half-life, inadequate targeting, limited clot penetration, and a propensity for severe bleeding. Inspired by the trident, we developed the armor-piercing microcapsule (MC), fucoidan-urokinase-S-nitrosoglutathione-polydopamine@MC (FUGP@MC), which exhibited a triple combination of photothermal, mechanical and pharmacological thrombolysis for the therapeutic treatment of acute pulmonary embolism (APE). Briefly, the outermost fucoidan layer was utilized for targeting to the APE area. Programmed APE treatment was triggered by near-infrared (NIR) light irradiation. Photothermal thrombolytic therapy was carried out by photothermal conversion of polydopamine. The photothermal conversion broke the S-nitroso bond in S-nitrosoglutathione (GSNO) and produced large amounts of nitric oxide (NO) for mechanical thrombolysis, which subsequently disrupted the interfacial structure of microcapsule to stimulate the release of the urokinase (UK), leading to a triple synergistic thrombolytic effect. The results demonstrated that the embolization residual rate of FUGP@MC (contained ≈ 1452.5 IU/kg UK) group was significantly lower than that of UK (10,000 IU/kg) group (6.35 % VS 16.78 %). Remarkably, FUGP@MC demonstrated a reliable in vivo biosafety proficiency. In summary, trident-inspired armor-piercing microcapsule FUGP@MC reveals a potential avenue for advancing pulmonary embolism therapeutics and promises to be a safer alternative candidate to current drug approaches.

In recent years, as a new type of quasi-zero-dimensional nanomaterials, graphene quantum dots (GQDs) have shown excellent performance in advanced drug targeted delivery and controlled release. In this work, the delivery process of model drugs translocating into POPC lipid membrane with the assistance of GQDs was investigated via molecular dynamics (MD) simulation. Our simulation results demonstrated that a single doxorubicin (DOX) or deoxyadenine (DA) molecule is difficult to penetrate into the cell membrane. GQD7 could form sandwich-like structure with DOX and assist DOX to enter into the POPC membrane. However, due to the weak interaction with DA, both GQD7 and GQD19 can not assist DA translocating the POPC membrane in the limited MD simulation time. The drug delivery process for DOX could be divided into two steps: 1. GQDs and DOX aggregated into a cluster; 2. the aggregates enter into the POPC membrane. In all our simulation systems, if GQDs loaded with model drugs and entered the cell membrane, it had little effect on the cell membrane structure, and the cell membrane could maintain high integrity and stability. These results may promote the molecular design and application of GQD-based drug delivery systems.

Porous polymer scaffolds are widely investigated as temporary implants in regenerative medicine to repair damaged tissues. While biocompatibility, degradability, mechanical properties comparable to the native tissues and controlled porosity are prerequisite for these scaffolds, their loading with pharmaceutical or biological active ingredients such as growth factors, in particular proteins, opens up new perspective for tissue engineering applications. This implies the development of scaffold loading strategies that minimize the risk of protein denaturation and allow to control their release profile. This work reports on a straightforward method for preparing bioactive dextran-based scaffolds from high internal phase emulsion (HIPE) templates containing poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) serving both as co-stabilizers for the emulsion and nanocarriers for drug or therapeutic protein models. Scaffold synthesis are achieved by photocuring of methacrylated dextran located in the external phase of a HIPE stabilized by the NPs in combination or not with a non-ionic surfactant. Fluorescent labelling of the NPs highlights their integration in the scaffold. The introduction of NPs, and even more so when combined with a surfactant, increases the stability and mechanical properties of the scaffolds. Cell viability tests demonstrate the non-toxic nature of these NPs-loaded scaffolds. The study of the release of a model protein from the scaffold, namely lysozyme, shows that its encapsulation in nanoparticles decreases the release rate and provides additional control over the release profile.