Colloids and Surfaces B: Biointerfaces最新文献

Ulcerative colitis (UC) is a chronic, recurrent inflammatory bowel disease marked by disturbances in intestinal mucosal barriers, persistent inflammation, oxidative stress, and dysbiosis of the intestinal microbiota. Traditional treatments often fail to adequately address these issues, primarily targeting inflammation. To address these limitations, this study developed an innovative approach using self-assembled nanoparticles for oral administration that target colonic inflammation. Berberine hydrochloride and ursodeoxycholic acid were combined to form a double salt (BeU), enhancing solubility and encapsulation. An amphiphilic polymer (FU-PA) was created by esterifying fucoidan with palmitic acid. FU-PA/BeU nanoparticles were prepared using the nanoprecipitation method and further encapsulated in acid-resistant sodium alginate microspheres (FU-PA/BeU NPs@MS) for targeted delivery to colonic lesions. The aggregation rate of nanoparticles with mucus was significantly reduced to 59 % of free berberine, while the apparent permeability coefficient increased by 2.4 times. In vitro, FU-PA/BeU NPs effectively targeted inflammatory macrophages, reducing IL-6 and NO levels while increasing IL-10 level (to 42.5 %, 26.8 %, and 539 % of the LPS-treated group, respectively). Additionally, the ABTS and DPPH radical scavenging capabilities of FU-PA/BeU NPs were 177.8 % and 151.7 % of BeU, respectively. In dextran sulphate sodium-induced UC mice, oral FU-PA/BeU NPs@MS significantly improved epithelial and mucosal barriers, restored gut microbiota diversity, reduced inflammation and oxidative stress. Remarkably, the mean colon length in the FU-PA/BeU NPs@MS group was 1.2 times longer than that in the sulfasalazine group. These dual-targeted FU-PA/BeU NPs@MS show great potential for UC treatment.

Current surface modification strategies for electrospun materials always require covalent conjugation technology, which is relatively inefficient and might damage the bioactivity and structure of peptides and proteins. Here we introduce the use of surface-induced self-assembly technology to modify electrospun materials, which is a simple but efficient noncovalent-based process. Results show that the peptide NapFFGRGD forms burr-like structures on the surface of PCL fibers, reducing the water contact angle of the fibers. Adjusting the peptide sequence and salt concentration affects the self-assembly and surface properties of modified PCL fibers. Additionally, we demonstrate the potential application of this surface modification technique for enhancing cellular responses in tissue engineering applications. The research provides valuable insights into the surface modification of PCL fibers and offers a new method for improving the biological compatibility of materials in tissue engineering.

Marine microbial corrosion poses a significant threat to the safe service of marine engineering equipment. Previous studies have often failed to thoroughly analyze the continuous and prolonged microbial corrosion process, resulting in an incomplete understanding of microbial corrosion mechanisms involved at various stages and the development of ineffective control strategies. This study employed a corrosion big data online real-time monitoring technique to investigate the time-dependent corrosion behavior of EH36 steel caused by Pseudomonas aeruginosa in aerobic environments over a 30-d incubation period. It was found that P. aeruginosa accelerated the corrosion of EH36 steel in the early stages by enhancing the cathodic oxygen reduction process. As oxygen levels declined, P. aeruginosa transitioned from aerobic to anaerobic respiration, promoting corrosion through biocatalytic nitrate reduction. In the later stages, the reduction in sessile cell counts, extreme low oxygen concentration, and dense surface film increased the charge transfer and film resistances, ultimately leading to corrosion inhibition. The weight loss and electrochemical data confirmed the effectiveness of the big data monitoring technique in investigating microbial corrosion, which provides new approaches for diagnosing and preventing microbial corrosion.

In the current study we fabricated potent materials by incorporating therapeutic elements into calcium phosphates (CPs) to combat cancer. This involved synthesizing manganese (Mn)- and lithium (Li)-doped CPs and loading them into electrospun nanofibers (NFs) composed of chitosan (CS) and polyethylene oxide (PEO). The characterized CPs exhibited excellent properties, including a particle size of 47-75 nm, surface charge of -(30-56) mV, and specific surface area of 75-266 m²/g. The electrochemical analysis revealed that Mn and Mn/Li-doped CPs are promising for generating oxygen free radicals and H₂O₂, crucial for cancer therapy. Biological evaluation showcased the outstanding performance of the developed materials. MTT assay revealed a cytotoxic effect of nano-constructs on melanoma A375 cell line without adverse effects on normal L929 cells over 72 h. Annexin V/PI apoptosis assay indicated substantial apoptosis rates in A375 cells treated with PC-20 % (62.55 ± 4.59 %). The obtained data of qPCR analysis of pro-apoptotic and anti-apoptotic genes (P53, Bax, Bcl-2) in A375 cells treated with different CP nanoparticles (NPs) showed a significant increase in P53 and Bax gene expression, indicating high levels of A375 cell apoptosis. Additionally, the samples containing Mn ion exhibited high reactive oxygen species (ROS) generation. In conclusion, the fabricated NFs scaffolds hold promising potential for cancer therapy.

Copper-based nanomaterials have the properties of mimetic enzymes and can be used as excellent candidates for colorimetric sensing due to their environmental friendliness, low cost, and high abundance. In this paper, Ni-doped Cu₂O nano cauliflower (Ni-Cu₂O) was synthesized for the first time and applied to the detection of H₂O₂ and uric acid (UA) in human serum and urine. It was found that the proportion of Ni incorporation controls the morphology and the catalytic effect of Ni-Cu₂O. The catalytic mechanism was studied by X-ray photoelectron spectroscopy, free radical capture experiments, photoluminescence spectroscopy, and steady-state kinetic analysis, which verified the redox reactions involving electron transfer and active substances. The results showed that Ni-Cu₂O could catalyze the formation of reactive oxygen species (•OH, O₂^•-, ₁O², h⁺) from H₂O₂, which could oxidize 3,3', 5,5'-tetramethylbenzidine (TMB) to oxTMB, and the color changed from colorless to blue. The Michaelis-Menten constant (K_m) and the maximum initial velocity (V_max) of Ni-Cu₂O were 1.8 mM and 15.2×10^-8 M/s, respectively. Based on the excellent peroxidase-like (POD) activity of Ni-Cu₂O, a colorimetric sensing platform combined with TMB was proposed to sensitively detect H₂O₂ and UA in a wide range, and the detection limits were as low as 0.17 μM and 0.22 μM, respectively. This study creates a platform for using the Cu-based cauliflowers as a biosensor to detect UA in the medical and biomedicine fields.

Uncontrolled bleeding from incompressible or irregularly shaped wounds is a major factor in the death of people in the battlefield or surgery process. Ideal rapid hemostatic materials should have the performance of rapid hemostasis and at the same time can be applied to a variety of complex wound trauma types, in addition, excellent antimicrobial properties, adhesion, biocompatibility, degradation, and the non-toxicity of degradation products are also necessary, but there are fewer hemostatic materials that meet these requirements. Herein, we prepared an injectable hemostatic hydrogel based on the natural products sodium alginate (SA) and carboxymethyl chitosan (CMC). Oxidized sodium alginate (OSA) was prepared by the oxidation reaction of NaIO₄ with SA, and OSA with aldehyde group was mixed with CMC with amino group to rapidly form an in situ injectable hemostatic hydrogel (OSA/CMC) by the Schiff base reaction. OSA/CMC hydrogel exhibited excellent antimicrobial and adhesion properties by the Schiff base reaction. In addition, OSA/CMC hydrogel directly activate the endogenous coagulation pathway through the synergistic effect of OSA, CMC to enhance the hemostatic effect. The results of in vivo hemostasis study showed that OSA/CMC hydrogel significantly accelerated hemostasis and reduced blood loss in liver hemorrhage model and tail amputation model. Therefore, OSA/CMC hydrogel is expected to be a potential material in the direction of rapid clinical hemostasis due to its good adhesion properties, antimicrobial properties, biocompatibility, blood compatibility, and efficient rapid hemostasis.

Immobilization of enzymes in porous organic framework (POF) materials is popular strategy to stabilize enzymes. For such solid enzyme catalysis system, improving the catalytic efficiency is challenging due to the diffusion resistance from solid-liquid interface and inner pores. Here, UCST-pH dual responsive polymeric carrier (PEG-b-PAAm-b-P(GMA-co-AAc)) was synthesized to immobilize cytochrome c (Cyt c), which impart the reversibly insoluble-soluble property to the immobilized Cyt c. The PEG-b-PAAm-b-P(GMA-co-AAc) could serve as an insoluble-soluble matrix to fast and efficiently immobilize Cyt c via covalent attachment, achieving a remarkable 92 % loading efficiency within just 120 min. The obtained insoluble PEG-b-PAAm-b-P(GMA-co-AAc)-Cyt c micelles exhibited an improvement in thermal, pH stability and reusability. The completely soluble PEG-b-PAAm-b-P(GMA-co-AAc)-Cyt c conjugates accelerated substrate diffusion and then enhanced the catalytic efficiency. These excellent advantages led to low detection limit (1.99 μM), lower than the presently reported biosensors based on enzyme mimics in the colorimetric detection of phenol. This UCST-pH dual responsive window presents a new platform to efficiently control the immobilization and release of enzymes, which will achieve excellent stability and catalytic efficiency.

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.

Acute kidney injury (AKI) is a common clinical problem with no effective treatment. Excessive folic acid (FA) induced kidney tubular injury is characterized by oxidative stress and inflammation, and is a common model of AKI. The excellent pharmacological activity of naringenin (NAR) makes it a potential agent for treating AKI, but its poor solubility limits its application. This study prepared NAR loaded nanoparticles (FU/PVP-NAR) using fucoidan (FU) and polyvinylpyrrolidone (PVP) as carriers, with a particle size of 23.96 ± 2.77 nm. In vitro studies showed that FU/PVP-NAR inhibited excessive FA induced proliferation inhibition, accumulation of reactive oxygen species (ROS), and disruption of mitochondrial membrane potential (MMP) of HK-2 cells. Further confirmed that FU/PVP-NAR inhibited FA induced DNA damage and Cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) activation. In vivo studies showed that excessive FA induced AKI features in mice, such as elevated serum creatinine (SCr) and blood urea nitrogen (BUN) levels, accompanied by pathological damage to kidney tissues. The above AKI characteristics induced by FA were alleviated by FU/PVP-NAR. FU/PVP-NAR also inhibited the decrease in antioxidant enzyme levels in kidney tissues induced by FA. Furthermore, in vivo mechanism studies indicated that FU/PVP-NAR inhibited the release of inflammatory factors by inhibiting DNA damage-cGAS-STING pathway. In summary, this study provided the possibility for FU/PVP-NAR as a potential candidate drug for treating FA induced AKI.