Biomimetic Membranes Research Articles

Seamless incorporation of artificial water channels in defect-free polyamide membrane for desalination of brackish water

Artificial water channels (AWCs) show the potential for overcoming the permeability-selectivity tradeoff of polyamide (PA) membranes. However, the availability of biomimetic materials and limitations posed by fabrication-induced defects make the development of AWC-PA membranes a daunting task. Herein, we synthesize imidazolylethyl-ureidoethyl-phenyl (IUP) compounds to form AWC by self-assembling and provide a strategy to seamlessly incorporate AWC in defect-free PA membranes. IUP compounds are molecularly designed with enhanced nature to form AWC due to π-π stacking interactions. In addition, nanosized colloid AWC aggregates can be obtained in water directly with the aid of sodium dodecyl sulfate (SDS) and conveniently incorporated into PA layers. The AWC not only promotes the preferential selective passage of water but also exhibits good compatibility with the surrounding PA matrix. The biomimetic membranes demonstrate a water permeance of 4.3 L·m−2·h−1·bar−1 and NaCl rejection of 99.3%, much higher than that observed with marketed state-of-the-art membranes. Mechanism understanding reveals that the compatible interaction between AWC, SDS and PA matrix is a necessary requisite to fabricate defect-free AWC-PA layers. This strategy can be easily extended to industrial scale and the biomimetic membranes may represent the development direction of the next generation of high-performance reverse osmosis membranes.

Ionophore-Based Molecular Layer-by-Layer Polyamide Membranes for Facilitated Single-Ion Transport.

Single-ion-selective membranes are indispensable for efficient ion separations in environmental, energy, and biomedical technologies. Inspired by biological ion channels, this work harnessed the selective and reversible ion binding features of ionophores to fabricate an ultrathin, ionophore-based K+-selective polyamide membrane through molecular layer-by-layer (m-LbL) polymerization with 18-crown-6-functionalized monomers. Compared with Cs+, Li+, and Mg2+, K+ exhibited the highest binding energy to 18-crown-6, facilitating its transport over the competing cations across the sub-10 nm polyamide film in a binary salt mixture. The need for competitive binding for selective K+ transport was further demonstrated through investigations of ion selectivity at varying concentration ratios between K+ and competing cations. Additionally, we extended the Nernst-Planck equation to describe individual ion flux in a binary system, identifying factors that govern ion transport. Our findings demonstrate the potential of selective single-ion transport enabled by preferential ion binding, showing promise for the development of biomimetic ion-selective polymeric membranes.

µ-Raman Spectroscopic Temperature Dependence Study of Biomimetic Lipid 1,2-Diphytanoyl-sn-glycero-3-phosphocholine

Raman spectroscopy is one of the best techniques for obtaining information concerning the physical–chemical interactions between a lipid and a solvent. Phospholipids in water are the main elements of cell membranes and, by means of their chemical and physical structures, their cells can interact with other biological molecules (i.e., proteins and vitamins) and express their own biological functions. Phospholipids, due to their amphiphilic structure, form biomimetic membranes which are useful for studying cellular interactions and drug delivery. Synthetic systems such as DPhPC-based liposomes replicate the key properties of biological membranes. Among the different models, phospholipid mimetic membrane models of lamellar vesicles have been greatly supported. In this work, a biomimetic system, a deuterium solution (50 mM) of the synthetic phospholipid 1,2-diphytanoyl-sn-glycero-3-phosphocholine (DPhDC), is studied using μ-Raman spectroscopy in a wide temperature range from −181.15 °C up to 22.15 °C, including the following temperatures: −181.15 °C, −146.15 °C, −111.15 °C, −76.15 °C, −61.15 °C, −46.15 °C, −31.15 °C, −16.15 °C, −1.15 °C, 14.15 °C, and 22.15 °C. Based on the Raman evidence, phase transitions as a function of temperature are shown and grouped into five classes, where the corresponding Raman modes describe the stretching of the (C−N) bond in the choline head group (gauche) and the asymmetric stretching of the (O−P−O) bond. The acquisition temperature of each Raman spectrum characterizes the rocking mode of the methylene of the acyl chain. These findings enhance our understanding of the role of artificial biomimetic lipids in complex phospholipid membranes and provide valuable insights for optimizing their use in biosensing applications. Although the phase stability of DPhPC is known, the collected Raman data suggest subtle molecular rearrangements, possibly due to hydration and second-order transitions, which are relevant for membrane modeling and biosensing applications.

Decellularised amniotic membrane-TDSCs composite promotes Achilles tendon healing

Adhesions and poor healing are major complications after Achilles tendon injury, and there is no effective solution to this problem. The purpose of this study is to determine whether the biomimetic peritoneurosis can solve the above problems in the process of Achilles tendon healing; This study investigated the adhesion and proliferation of tendon-derived stem cells (TDSCs) on dAM in vitro, as well as their tenogenic differentiation. The effects of Achilles tendon rupture on tendon regeneration were assessed in vivo by using an Achilles tendon rupture model in rats; Finally, from in vitro mRNA transcriptome sequencing combined with in vivo Achilles tendon protein to omics analysis to explore the repair mechanism of Achilles tendon rupture. Student’s t-tests were used to assess the significance of observed differences between the two experimental groups. Multiple groups were compared using one-way analysis of variances (ANOVAs), followed by post hoc Bonferroni comparisons. The main findings of this study are that cell adhesion, proliferation, and differentiation of TDSCs were enhanced by dAM. Implanted dAM + TDSCs significantly accelerated tendon regeneration in vivo. In addition, extracellular matrix-related differential genes and proteins were screened by mRNA transcriptometry in vitro and proteomic analysis of Achilles tendon in vivo, and ERK signaling pathway was further explored to participate in the repair of Achilles tendon rupture. The dAM-TDSCs composite biomimetic peritendinous membrane material can effectively promote the healing of Achilles tendon. It provides a new direction for the development of biomimetic peritendinous membrane materials.

Current Experience Using the Selective Cytopheretic Device for Continuous Immunomodulation in Acute Kidney Injury and Multiorgan Failure.

Introduction Sepsis and sepsis-associated acute kidney injury (AKI) are associated with increased patient morbidity and mortality. The immediate host response aimed at combating infection can become dysregulated, leading to uncontrolled inflammation and multi-organ failure, including AKI. Therapies targeting one protein component of the sepsis pathway have largely failed to improve patient outcomes, and currently only organ support therapies are used clinically to provide time for innate organ recovery to occur. The Selective Cytopheretic Device (SCD) is a continuous cell processing immunomodulatory device that attracts activated neutrophils and monocytes its biomimetic membrane surface. The activated leukocytes are transformed to a less pro-inflammatory phenotype and released back into the circulation when exposed to low ionized calcium concentration established in the SCD by standard regional citrate anticoagulation protocols used in continuous renal replacement therapy. Review In this review, we detail the history of the SCD and our experience with it, from discovery to pre-clinical testing to translational research application at the bedside. We discuss the SCD mechanism of action, its immunomodulatory effect, and the human studies involving critically ill adult pediatric patients with AKI who require continuous renal replacement therapy as part of the standard of care. We conclude discussing ongoing and future application of the SCD in both acute and chronic inflammatory states that would benefit from immunomodulation.

Cell membrane derived biomimetic nanomedicine for precision delivery of traditional Chinese medicine in cancer therapy.

Cell membrane derived biomimetic nanomedicine for precision delivery of traditional Chinese medicine in cancer therapy.

Curcumin-PLGA NPs coated with targeting biomimetic personalized stem cell membranes for osteoarthritis therapy.

Curcumin-PLGA NPs coated with targeting biomimetic personalized stem cell membranes for osteoarthritis therapy.

Mechanism of selenium-doped black phosphorus nanosheets wrapped with biomimetic tumor cell membrane for prostate cancer immunotherapy

Mechanism of selenium-doped black phosphorus nanosheets wrapped with biomimetic tumor cell membrane for prostate cancer immunotherapy

Skin-inspired elastomer-hydrogel Janus fibrous membrane creates a superior pro-regenerative microenvironment toward complete skin regeneration.

Skin-inspired elastomer-hydrogel Janus fibrous membrane creates a superior pro-regenerative microenvironment toward complete skin regeneration.

Evaluation of the antimicrobial efficiency of three novel chimeric peptides through biochemical and biophysical analyses.

Evaluation of the antimicrobial efficiency of three novel chimeric peptides through biochemical and biophysical analyses.

Exploring the influence of water micro assemblies on protein folding, enzyme catalysis and membrane dynamics.

Water is central to biological processes not only as a solvent, but also as an agent shaping macromolecular behavior. Insights into water micro assemblies (WMA), defined by transient regions of low-density water (LDW) and high-density water (HDW), have highlighted their potential impact on biological phenomena. LDW, with its structured hydrogen bonding networks and reduced density, stabilizes hydrophobic interfaces and promotes ordered molecular configurations. Conversely, HDW, with its dynamic and flexible nature, facilitates transitions, solute mobility and molecular flexibility. By correlating experimental observations with simulations, we explore the influence of WMA on three key biological processes. In protein folding, LDW may stabilize hydrophobic cores and secondary structures by forming structured exclusion zones, while HDW may introduce dynamic flexibility, promoting the resolution of folding intermediates and leading to dynamic rearrangements. In enzyme catalysis, LDW may form structured hydration shells around active sites stabilizing active sites over longer timescales, while HDW may support substrate access and catalytic flexibility within active sites. In membrane dynamics, LDW may stabilize lipid headgroups, forming structured hydration layers that enhance membrane rigidity and stability, while HDW may ensure the nanosecond-scale flexibility required for vesicle formation and fusion. Across these tree processes, the WMA's energy contributions, timescales and spatial scales align with the forces and dynamics involved, highlighting the role of LDW and HDW in modulating cellular interactions. This perspective holds implications for the design of lab-on-chip devices, advancements in sensor technologies, development of biomimetic membranes for drug delivery, creation of novel therapeutics and deeper understanding of protein misfolding diseases.

Emerita Analoga Shell-Derived CS/GO Composite Incorporated into a Biomimetic PAN Nanofiber Membrane for Enhanced Bone Tissue Regeneration.

Bone regeneration is a process that aims to restore the structure and function of damaged bone tissues. Modern approaches for bone regeneration involve a combination of strategies, including tissue engineering and biomaterials, to promote healing. In this study, electrospun nanofibers were developed by using biosynthesized chitosan (CS)- and graphene oxide (GO)-loaded polyacrylonitrile (PAN) nanofibers. These scaffolds demonstrated stable mechanical support and capability to promote rapid bone defect repair. The physicochemical properties of the prepared nanoparticles and nanofibers were characterized using XRD and XPS analysis. The nanofiber morphology and structure of the CS/GO composite were analyzed through SEM and TEM. In vitro studies and ALP activity demonstrated the membranes capability to promote new bone formation and support healing, and Alizarin red staining highlighted the membrane's ability to enhance cell-cell interactions and increase calcium deposition, crucial for tissue regeneration. Cytotoxicity analysis revealed that 97.66 ± 1.5% of MG-63 cells remained viable on the surface of the prepared nanofiber, as assessed by the MTT assay. At the molecular level, real-time RT-PCR was used to examine the mRNA expression of Runx2 and type 1 collagen. Promoting osteogenic gene expression and enhancing mineral deposition on the prepared nanofiber show significant potential in accelerating bone healing and ensuring the successful integration of the scaffold with the surrounding bone tissue. Based on these findings, we conclude that the CS/GO@PAN nanofibrous membrane holds significant promise as a substrate for bone regeneration.

Biomimetic membranes with waxberry-liked multiscale roughness for water-in-oil separation

Biomimetic membranes with waxberry-liked multiscale roughness for water-in-oil separation

Percutaneous penetration of typical Organophosphate esters under catalysis by Carboxylesterase: Characteristics, mechanism and prediction model.

Percutaneous penetration of typical Organophosphate esters under catalysis by Carboxylesterase: Characteristics, mechanism and prediction model.

A select inhibitor of MORC2 encapsulated by chimeric membranecoated DNA nanocage target alleviation TNBC progression.

A select inhibitor of MORC2 encapsulated by chimeric membranecoated DNA nanocage target alleviation TNBC progression.

Cell-free synthesis of membrane receptors for preparation of NKG2A monolithic micro-affinity chromatography.

Cell-free synthesis of membrane receptors for preparation of NKG2A monolithic micro-affinity chromatography.

Rolling vesicles: From confined rotational flows to surface-enabled motion

Friction forces are essential for cell movement, yet they also trigger numerous active cellular responses, complicating their measurement in vivo. Here, we introduce a synthetic model designed to measure friction forces between biomimetic membranes and substrates. The model consists of a vesicle with precisely controlled properties, fabricated via microfluidics, encapsulating a single ferromagnetic particle that is magnetically driven to rotate. The rotation of the particle generates a confined rotational flow, setting the vesicle membrane into motion. By adjusting the magnetic field frequency and vesicle size, the rotation frequency of the vesicle can be finely controlled, resulting in a rolling vesicle that functions as an effective tribological tool across a wide frequency range. At low frequencies, molecular contact between the membrane and substrate dominates frictional interactions, which enables determination of the contact friction coefficient. At higher frequencies, lubrication becomes predominant, causing the vesicles to slip rather than roll. Adjusting membrane fluidity and incorporating specific ligand-receptor interactions within this model will enable detailed studies of frictional forces in more complex biomimetic systems, providing key insights into the mechanisms of cell movement and mechanotransduction.

Active membrane deformations of a minimal synthetic cell

Abstract Living cells can adapt their shape in response to their environment, a process driven by the interaction between their flexible membrane and the activity of the underlying cytoskeleton. However, the precise physical mechanisms of this coupling remain unclear. Here we show how cytoskeletal forces acting on a biomimetic membrane affect its deformations. Using a minimal cell model that consists of an active network of microtubules and molecular motors encapsulated inside lipid vesicles, we observe large shape fluctuations and travelling membrane deformations. Quantitative analysis of membrane and microtubule dynamics demonstrates how active forces set the temporal scale of vesicle fluctuations, giving rise to fluctuation spectra that differ in both their spatial and temporal decays from their counterparts in thermal equilibrium. Using simulations, we extend the classical framework of membrane fluctuations to active cytoskeleton-driven vesicles, demonstrating how correlated activity governs membrane dynamics and the roles of confinement, membrane material properties and cytoskeletal forces. Our findings provide a quantitative foundation for understanding the shape-morphing abilities of living cells.

Neutrophil Hitchhiking-Mediated Delivery of ROS-Scavenging Biomimetic Nanoparticles for Enhanced Treatment of Atherosclerosis.

Atherosclerosis (AS), a chronic inflammatory disease and a leading cause of cardiovascular morbidity and mortality worldwide, is a significant contributor to disability. Neutrophil extracellular traps (NETs) have been closely associated with the progression of AS and plaque vulnerability. However, developing a treatment strategy that specifically targets neutrophils and effectively reduces NET release at the lesion site remains a major challenge. In this study, a biomimetic nanosystem with neutrophil-targeting properties is engineered. Coating Prussian blue nanoparticles with bacterial biomimetic membranes (MPB NPs) enables specific recognition and internalization by neutrophils. By hitching onto neutrophils, the MPB NPs scavenge intracellular reactive oxygen species (ROS) and suppress NET formation at the lesion site. Importantly, MPB NPs reduce the size of atherosclerotic plaques by 3.29-fold, from 22.53% to 6.85%, stabilize the plaques, and halt their progression in atherosclerotic mouse models. These findings suggest that MPB NPs offer a promising therapeutic strategy for atherosclerosis, and provide a versatile platform for the treatment of NET-associated diseases.

Dynamics of Microsphere Inclusions within Biomimetic Membranes Reveal Membrane Heterogeneity.

Extracellular macromolecules and particles often bind and diffuse over cell membranes during transport processes like endocytosis, exocytosis, drug imbibition, etc. However, imaging the real-time dynamics of these phenomena at nanometer scale resolution is highly challenging. Here, we use a model system of polystyrene microspheres diffusing over the surface of colloidal membranes as 3 orders of magnitude scaled up analogue of this process. Colloidal membranes are freely fluctuating two-dimensional smectic A monolayers of one micrometer long rod-shaped viruses that bind to polystyrene microspheres through the generic mechanism of depletion attraction. We find that the microsphere causes local deformation in the membrane, behaving as an inclusion that diffuses freely in the bulk of the membrane but surprisingly gets radially trapped near the edge of the membrane. We identify the critical particle size and membrane composition required to observe trapping of particles at the membrane edge. A quantitative analysis of the motion of the particle in the bulk enabled us to determine the local membrane interfacial viscosity of the colloidal membranes. Overall, our study shows that the complex interplay of membrane fluctuations and particle characteristics can lead to a rich phenomenology even in highly simplified few component model systems.