Colloids and Surfaces B: Biointerfaces最新文献

Orthogonal multimodal therapy is a highly effective strategy for tumor ablation, yet they require nanomedicines with complex structures that are difficult to use practically. Here, a structurally simple nanomedicine is constructed by independently modified boron-doped carbon quantum dots (B-CDs) with nicorandil by physical absorption and epigallocatechin gallate (EGCG) through borate ester bonding, respectively. In the redox-imbalance tumor microenvironment, nicorandil (NIC) produce NO for gas therapy in response to intratumoral GSH and HSP90 is inhibited due to H₂O₂-triggered EGCG release, while B-CDs generate local hyperthermia under near-infrared light. Therefore, this nanomedicine can exercise specific therapeutic modes in response to different tumor microenvironmental characteristics or external stimuli under fluorescence supervision.

Astrocytes are key supportive cells in the central nervous system (CNS), responsible for neural repair, synapse formation, and maintaining neural health. In this work, the optimization of crosslinking treatments to fabricate polyvinyl alcohol (PVA)/gelatin electrospun nanofibers was investigated to remark the effect of chemical - i.e., gelatin - and topological - i.e., fiber orientation - cues on the in vitro activity of mouse astrocytes. Fiber morphology deeply explored via Scanning Electron Microscopy (SEM)/image analysis highlighted a significant decay of the average diameter as the gelatin content - from 0.955 ± 0.146 μm (7:3) to 0.599 ± 0.1 μm (5:5) - or in the presence of preferential fiber alignment - 0.662 ± 0.204 μm (7:3). Assessment of the cell survival revealed that astrocytes were better able to survive and proliferate on nanofibers with gelatin than on those without any addition of gelatin nanofibers. In this context, the alignment of nanofibers enhanced not only the attachment of astrocytes but also their spatial orientation playing a critical role in directing the growth of astrocytes as confirmed by immunofluorescence studies. The electrospun PVA/gelatin (PVAG) structures, especially with uniaxial fiber orientation, proved to be a potential substrate for the culture of astrocytes and construction of CNS tissues. The role of biological macromolecules, such as gelatin, allows to support in vitro astrocyte function, thus offering new avenues for neural tissue engineering and regenerative medicine.

Wearable sensors for detecting ethanol volatile organic compounds (VOCs) in sweat offer a non-invasive approach to monitor liver health. In line with this goal, a titanium dioxide/polyaniline (TiO₂/PANI) nanocomposite-based sensor electrode was developed for real-time ethanol detection under standard conditions (300 K, 1 atm). The thin film, deposited on a conductive fabric, was characterized for phase, structure, and morphology. Electrochemical tests showed high sensitivity, with a detection limit of 23.62 ppb and quantification of 71.59 ppb. The sensor demonstrated excellent reproducibility, stability, and selectivity across various ethanol concentrations. It effectively distinguished between sweat samples from healthy and liver-affected individuals and maintained performance over 100 days under varying humidity and temperature.

Surface-active peptides (SAPs) typically mimic conventional surfactants by featuring long non-polar (hydrophobic) peptide tails and short polar (hydrophilic) heads consisting of a single amino acid or short peptide. However, reverse-structure SAPs-with a long hydrophilic tail and short hydrophobic head-remain largely unexplored. If developed, such SAPs could form micelles with a larger hydrophilic area and a smaller hydrophobic core, leading to novel self-assembled structures. We hypothesize that combining the self-assembly potential of an aromatic moiety as a short hydrophobic head with the linear hydrophilic properties of collagen-like peptides containing Glycine-Proline-Hydroxyproline (GPO) repeats can lead to the development of these unique reverse SAPs. These SAPs are expected to form unique self-assembled structures with a larger hydrophilic area and a smaller hydrophobic core, contributing to advancements in colloidal and interface science. To validate this hypothesis, π-system-functionalized collagen-like peptides were designed using (GPO)_n (n = 1-5) as extended hydrophilic tails and a fluorenyl aromatic π-system as the hydrophobic head. Biophysical studies evaluated their self-assembly, critical micellar concentration, and surface activity, focusing on stabilization mechanisms driven by aromatic π-π interactions and hydrogen bonding. The SAPs exhibited surface activity and formed micelles at sub-millimolar concentrations. Longer hydrophilic tails resulted in lower CMC values, indicating enhanced self-assembly. The micelles were stabilized by π-π stacking and hydrogen bonding, creating unique self-assembled structures with a larger hydrophilic region and a smaller hydrophobic core. These findings provide new insights into colloids and interface science and open avenues for applying reverse-structure SAPs in drug delivery.

Mannosylated poly(lactic-co-glycolic acid) (PLGA) nanoparticles encapsulating Eucommia ulmoides polysaccharides (EOPP) were developed as a targeted immunomodulatory delivery system. In vitro evaluations confirmed that EOPP exhibited low cytotoxicity toward spleen lymphocytes while significantly increasing their proliferation and cytokine secretion (IL-6 and IFN-γ). When co-delivered with ovalbumin (MN-EOPP/OVA), the system further enhanced the secretion of TNF-α, IL-12, IL-6, and IFN-γ by immune cells and induced cytoskeletal remodeling and maturation in bone marrow-derived dendritic cells (BMDCs). Transcriptomic profiling revealed significant upregulation of immune-related genes, with KEGG and PPI analyses identifying activation of key signaling pathways, including MAPK (ERK, p38, JNK) and NF-κB. These pathways drive the expression of genes involved in antigen processing and dendritic cell function. Overall, MN-EOPP/OVA effectively enhanced both humoral and cellular immune responses by synergistic delivery of antigen and immunopotentiator, supporting its potential as a next-generation vaccine adjuvant strategy.