Nazely Diban

Negative pressure wound therapy (NPWT) is widely used to facilitate healing by improving local perfusion, reducing edema and controlling exudate. The porous foam dressing is central to NPWT effectiveness, however, its performance in viscous, particle‐rich exudates remains challenging. Standard industry tests often rely on protein‐free aqueous solutions, which overlook the complex rheology and particulate load of real wounds. This study reports a bench evaluation of a multilayer foam prototype compared with three commercial dressings under NPWT, using a simulated viscous exudate with suspended particles. We recorded 60‐min drainage curves and quantified effluent turbidity as a simple, interpretable proxy for particulate transport, summarised as percentage of input turbidity recovered. The mass‐based endpoint (percent solid matter recovered) showed the same ranking as turbidity. At −75 mmHg, the prototype recovered 31.6% of input turbidity, exceeding commercial foams (≤ 9.7%). At −125 mmHg, particulate recovery decreased across all dressings (≤ 9.1%). A matrix‐only control indicated that commercial effluents, particularly at −75 mmHg, clustered near background level, whereas the prototype evacuated substantially more particulate while maintaining robust fluid drainage. These findings suggest that moderate negative pressure and multilayer architecture can help preserve channel patency and reduce clogging in complex exudates. We highlight the need for test methodologies that incorporate viscosity and particulate content, and for practical guidance that links dressing architecture and pressure settings to exudate characteristics. Prospective validation, including larger‐sample confirmation, particle‐size distributions and ultimately clinical endpoints, is warranted.

This study presents first polymeric hollow fibers (HFs) with sufficient optical transparency for real‐time and non‐invasive monitoring of biological systems, one of the most important hurdles accounted in HF bioreactor technology. Biocompatible polymers, including polyvinylidene fluoride (PVDF), polycaprolactone, and polyacrylonitrile, were processed via dry‐jet wet spinning. A comprehensive analysis of the morphological, structural, and transport properties of the HFs provided valuable insights into their optical performance. Our findings revealed the critical interplay of HF wall thickness, porosity, polymer crystal size, and intrinsic refractive index in achieving transparency. These findings may serve as a useful guidance to produce transparent polymeric HFs with similar or different polymeric systems. Remarkably, PVDF HFs achieved over 83% transmittance, exceeding standards for in vitro cell observation, and was achieved without the presence of modifiers. As a proof of concept, labeled human cerebral microvascular endothelial cells (hCMEC/D3) were cultured within the HFs and successfully monitored in real time under both static and dynamic conditions. These transparent HFs demonstrate transformative potential, enabling real‐time decision making while significantly reducing cost and time. This cutting‐edge membrane material paves the way for advanced applications in microfluidics, mass transport studies, and biomedical research, establishing these transparent HFs as key enabling materials for strategic biomedical technologies.

This work presents a novel semiempirical mathematical approach consisting of a coupled thermo‐kinetic model as valuable tool for predicting the polymeric fraction profile of membranes synthesized by nonsolvent induced phase separation (NIPS). Equilibrium binodal curves (BCs) of the system component were incorporated to the Fick’s diffusive kinetic model allowing a satisfactory prediction of the tendency to develop symmetric or asymmetric porous membrane morphologies, as well as a fair quantification of average porous fraction profiles. The model was validated using two different ternary systems: (i) polycaprolactone (PCL)/N‐methylpyrrolidone (NMP)/water (W) characteristic of instantaneous demixing (asymmetric finger‐like porous cross‐section morphology); and (ii) PCL/NMP/isopropanol (IPA) characteristic of delayed demixing (symmetric sponge‐like cross‐section morphology). The loading of graphene oxide (GO) in the quaternary system PCL/GO/NMP/IPA also gave rise to a sponge‐like porosity, characteristic of delayed demixing systems, which was reasonably predicted by the coupled thermo‐kinetic model developed in this study. In addition, a computational scanning electron microscopy (SEM) image processing methodology was developed to validate the thermo‐kinetic model, resulting in an advantageous tool for that purpose. Overall, this work reveals the usefulness of the new thermo‐kinetic mathematical approach as a facile computational tool for membrane manufacturers and researchers for a preliminary discrimination of component combinations in quaternary polymer/nanofiller/solvent/nonsolvent NIPS systems.

This work presents the photocatalytic degradation of organic pollutants in water with TiO₂ and TiO₂/Ag membranes prepared by immobilising photocatalysts on ceramic porous tubular supports. The permeation capacity of TiO₂ and TiO₂/Ag membranes was checked before the photocatalytic application, showing high water fluxes (≈758 and 690 L m⁻² h⁻¹ bar⁻¹, respectively) and 2 particles (1.1-fold and 1.2-fold increase, respectively). However, when the aqueous solution permeated through the pores of the photocatalytic membrane, the performance factors and kinetics were two-fold higher than for the submerged membranes, mostly due to the enhanced contact between the pollutants and the membranes photocatalytic sites where reactive species were generated. These results confirm the advantages of working in a flow-through mode with submerged photocatalytic membranes for the treatment of water polluted with persistent organic molecules, thanks to the reduction in the mass transfer limitations.

With the increasing concern of neurodegenerative diseases, the development of new therapies and effective pharmaceuticals targeted to central nervous system (CNS) illnesses is crucial for ensuring social and economic sustainability in an ageing world. Unfortunately, many promising treatments at the initial stages of the pharmaceutical development process, that is at the in vitro screening stages, do not finally show the expected results at the clinical level due to their inability to cross the human blood-brain barrier (BBB), highlighting the inefficiency of in vitro BBB models to recapitulate the real functionality of the human BBB. In the last decades research has focused on the development of in vitro BBB models from basic 2D monolayer cultures to 3D cell co-cultures employing different system configurations. Particularly, the use of polymeric hollow fiber membranes (HFs) as scaffolds plays a key role in perfusing 3D dynamic in vitro BBB (DIV-BBB) models. Their incorporation into a perfusion bioreactor system may potentially enhance the vascularization and oxygenation of 3D cell cultures improving cell communication and the exchange of nutrients and metabolites through the microporous membranes. The quest for developing a benchmark 3D dynamic in vitro blood brain barrier model requires the critical assessment of the different aspects that limits the technology. This article will focus on identifying the advantages and main limitations of the HFs in terms of polymer materials, microscopic porous morphology, and other practical issues that play an important role to adequately mimic the physiological environment and recapitulate BBB architecture. Based on this study, we consider that future strategic advances of this technology to become fully implemented as a gold standard DIV-BBB model will require the exploration of novel polymers and/or composite materials, and the optimization of the morphology of the membranes towards thinner HFs (via regulatory factors between the cell co-culture models of the BBB.

Composites of polymer and graphene-based nanomaterials (GBNs) combine easy processing onto porous 3D membrane geometries due to the polymer and cellular differentiation stimuli due to GBNs fillers. Aiming to step forward to the clinical application of polymer/GBNs composites, this study performs a systematic and detailed comparative analysis of the influence of the properties of four different GBNs: (i) graphene oxide obtained from graphite chemically processes (GO); (ii) reduced graphene oxide (rGO); (iii) multilayered graphene produced by mechanical exfoliation method (G_mec); and (iv) low-oxidized graphene via anodic exfoliation (G_anodic); dispersed in polycaprolactone (PCL) porous membranes to induce astrocytic differentiation. PCL/GBN flat membranes were fabricated by phase inversion technique and broadly characterized in morphology and topography, chemical structure, hydrophilicity, protein adsorption, and electrical properties. Cellular assays with rat C6 glioma cells, as model for cell-specific astrocytes, were performed. Remarkably, low GBN loading (0.67 wt%) caused an important difference in the response of the C6 differentiation among PCL/GBN membranes. PCL/rGO and PCL/GO membranes presented the highest biomolecule markers for astrocyte differentiation. Our results pointed to the chemical structural defects in rGO and GO nanomaterials and the protein adsorption mechanisms as the most plausible cause conferring distinctive properties to PCL/GBN membranes for the promotion of astrocytic differentiation. Overall, our systematic comparative study provides generalizable conclusions and new evidences to discern the role of GBNs features for future research on 3D PCL/graphene composite hollow fiber membranes for in vitro neural models.

In this work, we performed a methodological comparative analysis to synthesize polyethyleneimine (PEI) nanoparticles using (i) conventional nanoprecipitation (NP), (ii) electrospraying (ES), and (iii) coaxial electrospraying (CA). The nanoparticles transported antisense oligonucleotides (ASOs), either encapsulated (CA nanocomplexes) or electrostatically bound externally (NP and ES nanocomplexes). After synthesis, the PEI/ASO nanoconjugates were functionalized with a muscle-specific RNA aptamer. Using this combinatorial formulation methodology, we obtained nanocomplexes that were further used as nanocarriers for the delivery of RNA therapeutics (ASO), specifically into muscle cells. In particular, we performed a detailed confocal microscopy-based comparative study to analyze the overall transfection efficiency, the cell-to-cell homogeneity, and the mean fluorescence intensity per cell of micron-sized domains enriched with the nanocomplexes. Furthermore, using high-magnification electron microscopy, we were able to describe, in detail, the ultrastructural basis of the cellular uptake and intracellular trafficking of nanocomplexes by the clathrin-independent endocytic pathway. Our results are a clear demonstration that coaxial electrospraying is a promising methodology for the synthesis of therapeutic nanoparticle-based carriers. Some of the principal features that the nanoparticles synthesized by coaxial electrospraying exhibit are efficient RNA-based drug encapsulation, increased nanoparticle surface availability for aptamer functionalization, a high transfection efficiency, and hyperactivation of the endocytosis and early/late endosome route as the main intracellular uptake mechanism.

Background Recent advances from studies of graphene and graphene-based derivatives have highlighted the great potential of these nanomaterials as migrastatic agents with the ability to modulate tumor microenvironments. Nevertheless, the administration of graphene nanomaterials in suspensions in vivo is controversial. As an alternative approach, herein, we report the immobilization of high concentrations of graphene nanoplatelets in polyacrylonitrile film substrates (named PAN/G10) and evaluate their potential use as migrastatic agents on cancer cells. Results Breast cancer MCF7 cells cultured on PAN/G10 substrates presented features resembling mesenchymal-to-epithelial transition, e.g., (i) inhibition of migratory activity; (ii) activation of the expression of E-cadherin, cytokeratin 18, ZO-1 and EpCAM, four key molecular markers of epithelial differentiation; (iii) formation of adherens junctions with clustering and adhesion of cancer cells in aggregates or islets, and (iv) reorganization of the actin cytoskeleton resulting in a polygonal cell shape. Remarkably, assessment with Raman spectroscopy revealed that the above-mentioned events were produced when MCF7 cells were preferentially located on top of graphene-rich regions of the PAN/G10 substrates. Conclusions The present data demonstrate the capacity of these composite substrates to induce an epithelial-like differentiation in MCF7 breast cancer cells, resulting in a migrastatic effect without any chemical agent-mediated signaling. Future works will aim to thoroughly evaluate the mechanisms of how PAN/G10 substrates trigger these responses in cancer cells and their potential use as antimetastatics for the treatment of solid cancers.

Immobilization of photocatalysts in porous materials is an approach to significantly minimize the hazards of manipulation and recovery of nanoparticles. Inorganic materials, such as zeolites, are proposed as promising materials for photocatalyst immobilization mainly due to their photochemical stability. In this work, a green synthesis method is proposed to combine TiO₂-based photocatalysts with commercial ZY zeolite. Moreover, a preliminary analysis of their performance as photocatalysts for the abatement of organic pollutants in waters was performed. Our results show that the physical mixture of TiO₂ and zeolite maintains photocatalytic activity. Meanwhile, composites fabricated by doping TiO₂–zeolite Y materials with silver and palladium nanoparticles do not contribute to improving the photocatalytic activity beyond that of TiO₂.