Biointerphases最新文献

Mass spectrometry (MS) often requires vacuum conditions, which, while beneficial for analysis, can unpredictably alter sensitive samples. This study investigates the impact of prolonged vacuum exposure on the consistency and reliability of MS detection of thin films of acetaminophen using secondary ion mass spectrometry (SIMS). Under vacuum at room temperature, the mass spectrometry signal intensity decreased by approximately 81.5% over the duration of the experiment (42 h). Optical microscopy revealed that this decrease coincided with sublimation-induced sample loss of the acetaminophen. As a result, acetaminophen coverage across the substrate became heterogeneous, leading to increased relative standard deviation (RSD) in the SIMS signal over time. In contrast, under cryogenic conditions, neither signal degradation nor an increase in RSD was observed. Additionally, a comparison with atmospheric pressure mass spectrometry revealed that, in the absence of vacuum, signal intensity remained more stable over time. These findings highlight the potential drawbacks of vacuum exposure for volatile standards and emphasize the importance of testing vacuum effects prior to analysis. If vacuum is necessary, cryogenic conditions should be considered to mitigate sample degradation. While these effects were observed for a mass spectrometry technique, they are also applicable to any type of vacuum-based methodology where the samples might be prone to sublimation.

The lack of cementum in peri-implant tissues leads to a deficiency in anchorage points for gingival collagen fibers. This arrangement is linked to reduced protective capabilities compared to teeth. Therefore, there is a pressing need to develop surfaces that optimize the interaction between soft tissue and implants. 3D-printed titanium disks (Ti3DP), machined disks (TiMC), and glass coverslips (GS) were seeded with human gingival fibroblasts. These specimens underwent mechanical characterization via roughness and wettability assays. Biological characterization included assessments of cellular viability (live/dead), adhesion and spreading (F-actin), cell count (DAPI), cellular metabolism (Alamar blue), adhesive strength, and soluble collagen and total protein quantification up to 14 days. Data analysis employed Student's t-test and ANOVA post-hoc Tukey test (α = 0.05). The group TiMC exhibited higher hydrophilicity and lower roughness compared to Ti3DP. All groups demonstrated cellular viability throughout the study period. Adhesive strength did not significantly differ among groups; however, cell count was higher in TiMC and GS after one day of cell seeding in comparison to Ti3DP. Morphologically, GS and TiMC displayed more fusiform cells with a uniform distribution, while Ti3DP showed smaller, irregular cells with multiple lamellipodia and filopodia. Additionally, statistically superior collagen and total protein deposition was observed in Ti3DP (p < 0.01). The 3D-printed titanium surface allowed human gingival fibroblasts to adhere to it, leading to a 3D cytoskeleton morphology that culminated in increased collagen expression. Therefore, these 3D-printed devices present a promising avenue for producing transmucosal components due to their increase in collagen production.

Bioactive herbal extracts have garnered significant attention due to their multitarget regulation and low toxicity, yet their clinical applications are limited by poor solubility, low bioavailability, and insufficient targeting. This review systematically summarizes the pharmacological properties of terpenoids, alkaloids, flavonoids, polysaccharides, and other components, and explores their synergistic integration with biomaterials such as nanoparticle delivery systems, microneedles, and hydrogels. Functionalized nanocarriers enhance the stability and targeting efficiency of paclitaxel, berberine, and other bioactive herbal extracts. Microneedle technology leverages physical penetration and sustained-release mechanisms to achieve efficient transdermal delivery of bioactive herbal extracts (e.g., aconitine, curcumin, and similar agents). Smart hydrogels incorporating active molecules (e.g., baicalin and icariin) achieve spatiotemporal precision in wound healing and osteoarthritis treatment through pH-/enzyme-/reactive oxygen species-responsive release mechanisms. Additionally, the combination of herbal extracts with stents or bone cement expands their potential in cardiovascular and bone regeneration applications. While these integrated systems demonstrate synergistic effects in antitumor, anti-inflammatory, and tissue repair, challenges remain in scalable manufacturing, in vivo metabolic mechanisms, and long-term biosafety. Future research should integrate smart biomaterial designs and multiomics analysis to establish a comprehensive "component-carrier-efficacy" development framework, advancing the convergence of bioactive herbal extracts and modern medical science.

Poly(ɛ-caprolactone) (PCL) remains widely studied in biomaterials science and biomedical engineering due to its versatility and applicability in regenerating a range of tissues including bone, cartilage, neural, and cardiovascular. Due to the hydrophobicity of PCL, most PCL based systems for tissue regeneration require a surface modification process to enhance its in vitro and in vivo compatibility. This Perspective aims to provide an overview of recent strategies used to modify 2D films and 3D scaffolds and the associated methods used to characterize these surfaces. The scope is restricted to physical and chemical postmodification methods, excluding blends and composites, to better isolate the effects of surface chemistry. By analyzing the latest studies (published in 2022-2024), we classified the most commonly employed surface modification techniques, and we identified that the surface evaluation of tailored PCL remains a critical challenge in terms of both chemical and morphological characterization as well as the stability of the introduced surface layer/coating. This status of recent literature highlights current excellent practices and characterization methodologies and suggests approaches for refining surface engineering methods of PCL-based biomaterials in the future.

The disruption of protein structures by denaturants such as urea is well-documented, although the underlying molecular mechanisms are not yet fully understood. In this study, we employed molecular dynamics simulations to examine the effects of urea on the structural stability of bovine serum albumin (BSA) at concentrations ranging from 0 to 5M. Our results reveal that urea induces a dehydration-rehydration cycle by displacing and partially substituting water molecules in BSA's hydration shell. At lower concentrations, urea decreases protein-water hydrogen bonding while enhancing protein-urea interactions. At higher concentrations, urea tends to aggregate, which limits direct interactions with the protein, promotes rehydration, and leads to alterations in the tertiary structure, although the secondary structure remains largely preserved. These findings offer mechanistic insights into urea-induced protein denaturation and stability.

An immunological atomic force microscopy technique was used to recognize fibrinogen adsorption and functional activity on polyurethane biomaterial surfaces in the presence of other proteins. The amount of fibrinogen adsorbed on surfaces as recognized by an antifibrinogen polyclonal antibody when in competitive adsorption with human serum albumin (HSA) or human IgG was found to be related to the molar ratio of proteins. A significant decrease in fibrinogen adsorption was observed only when the fraction of smaller proteins reached a threshold value, dependent on smaller protein properties. The functional activity of fibrinogen was measured by a monoclonal antibody recognizing a region containing the dodecapeptide sequence located at the C-terminus of the γ-chain, γ-400-411. Results show that the presence of smaller proteins affected the conformational structure of fibrinogen and increased the availability of platelet binding sites in fibrinogen adsorbed on surfaces. Platelet adhesion was performed on polyurethane surfaces, which were competitively preadsorbed with fibrinogen and HSA. Platelet adhesion correlated well with the functional activity of fibrinogen, measured after competitive adsorption on surfaces. The work suggests that platelet adhesion is not necessarily determined by the amount of adsorbed fibrinogen but is related to the activity of fibrinogen as measured by the availability of the platelet binding sites in the fibrinogen, γ-chain dodecapeptide.

Phenylketonuria, a congenital metabolic defect, has been identified as a consequence of the formation of toxic l-phenylalanine fibrillar self-assembly under millimolar concentration in blood. Here, we have studied the influence of l-phenylalanine on the model lipid membrane like 1,2-diacyl-sn-glycero-phosphocholine and 1,2-dimyristoyl-sn-glycero-3-phosphocholine in the aqueous medium with millimolar concentration. The bilayers of the phospholipid vesicles are deformed after the interaction with phenylalanine, which is monitored through the fluorescence lifetime imaging microscopic study. The rigidity and shape of the phospholipid vesicles are recovered after the introduction of a short hydrocarbon chain containing imidazolium ionic liquid, 1-ethyl-3-methylimidazolium hexafluorophosphate ([C2mim]PF6). The long-chain imidazolium ionic liquid, 1-methyl-3-nonylimidazolium hexafluorophosphate (C9mim]PF6), further distorted, fused, and decreased the rigidity of the vesicle bilayer.

Bacterial motility is essential for navigating heterogeneous environments like soil, where it plays a key role in nutrient cycling, bioremediation, and overall soil health. Despite its importance, the interplay between bacterial motility and soil microstructures-such as the effects of physical confinement and interfacial interactions-remains underexplored. In this study, we investigated the motility of Escherichia coli bacteria in aqueous micro-environments with three different natural soil samples and examined how the particle size, void fraction, and proximity to soil particles affect bacterial motility and movement patterns by quantitatively analyzing bacterial trajectories, velocities, and directional changes. We observed that bacterial velocity decreased significantly in soil micro-environments, showing a strong positive correlation with the soil particle size and a negative correlation with the void fraction of the soil samples. Additionally, bacteria in soil micro-environments showed rapid and dramatic directional changes, and the rate of directional changes of bacteria was negatively correlated with the particle size. These results were further validated with synthetic micro-environments with glass microspheres. As the density of microspheres increased, the translational velocity of bacteria decreased while the directional changes increased. This study enhances our understanding of how the soil type, porosity, and particle proximity impact bacterial movement and is expected to contribute to a better understanding of bacterial activities on soil health and management.

Exosomes are one of the extracellular vesicles that are secreted by almost all cell types and body fluids. Because they are nanosized (30-200 nm), they can be used as natural nanovesicles. Exosomes have recently been preferred for their low immunogenicity and toxicity features for cell-free therapy, nano-drug carriers, and regenerative medicine. Rapid and appropriate exosome isolation has become increasingly critical due to its extensive application area. In this study, we isolated the MCF-7 cell exosomes using a biological membrane that works for nanoparticle isolation. Our results showed that the number of exosomes was 2 × 106 particles per ml in the cell line media, with a peak size of 110 nm. The proposed technique has features such as simplifying the operative procedures, low cost, and high efficiency. In addition, this technique did not use high-cost reactants, and it was not time-consuming. Additionally, no further procedure was necessary, and the amount of hand manipulation was minimal.

G-quadruplexes (G4) have been proposed as an alternative target for cancer therapy, as the folding of DNA sequences into stabilized G4 in the cancer microenvironment affects key biological functions. The antimalarial drugs, hydroxychloroquine (HCQ) and chloroquine (CQ), are in the clinical trial stage for cancer therapy and have been found to fold DNA sequences into the stabilized G4 even in the absence of KCl salt. In this study, the role of loop nucleobases in terms of chemical nature, number, and location in the HCQ-/CQ-induced folding of DNA sequences into G4 in the absence of KCl has been investigated systematically. The data indicate that both drugs selectively induce the folding of DNA sequences into G-quadruplexes (G4) that contain thymine loop nucleobases. The folding tendency of DNA sequences into stabilized G4 decreases with the increase in the thymine loop nucleobases. Moreover, DNA sequences with fewer thymine loop nucleobases tend to fold into stable G4 when the thymine residues are present at the terminal positions, whereas sequences with more thymine loop nucleobases show higher G4 folding propensity when these bases are located at the central loop. These findings are important in understanding the anticancer effect of antimalarial drugs.