Self-assembly Process Research Articles

Polydopamine-assisted immobilization of metallic nanoparticles confined regionally in bamboo microchannels as continuous-flow microreactors for enhanced catalysis

In contrast to conventional plant-based microreactors where the nanocatalyst is anchored on the inner walls of microchannel structures, this study presents a bamboo-based flow microreactor in which the metallic nanocatalyst is immobilized within polydopamine (PDA) region-modified bamboo microchannels. This novel design facilitates a large surface area for nanocatalyst loading, enhances mass transfer, and reduces nanocatalyst leaching. Firstly, the hierarchical PDA architecture was fabricated on the wall surface of required bamboo microchannels through an ammoniation-induced self-assembly process to serve as a nanocatalyst support layer. The thickness of PDA architectures was modulated by adjusting the flow duration. Secondly, the metallic nanoparticles (NPs), including Pd, Au, and Ag, were effectively immobilized within the hierarchical PDA architectures as highly efficient catalysts using a flow-assisted method with minimal chemical usage and low catalyst loading (Pd content: 0.011 wt%). The catalytic performances of the proposed Pd-PDA/bamboo microreactor were evaluated for the continuous hydrogenation of nitroaromatics under flow conditions, encompassing variations in Pd content, nitroaromatic concentration, and liquid flow rate. The optimized Pd-PDA/bamboo microreactor exhibited high average conversion (>97 %) of nitroaromatics during 20 days of continuous operation without any noticeable deactivation or loss in activity due to its excellent stability resulting from firm immobilization of active metallic NPs within hierarchical PDA architectures. Additionally, this bamboo microreactor demonstrated potential applicability in environmental pollution treatment through azo dye hydrogenation.

Pluronic-Based Nanoparticles for Delivery of Doxorubicin to the Tumor Microenvironment by Binding to Macrophages.

The active targeting drug delivery system based on special types of endogenous cells such as macrophages has emerged as a promising strategy for tumor therapy, owing to its tumor homing property and biocompatibility. In this work, the active tumor-targeting drug delivery system carrying doxorubicin-loaded nanoparticles (DOX@MPF127-MCP-1, DMPM) on macrophage (RAW264.7) surfaces via the mediation of interaction with the CCR2/MCP-1 axis was exploited. Initially, the amphiphilic block copolymer Pluronic F127 (PF127) was carboxylated to MPF127 at the hydroxyl terminus. Subsequently, MPF127 was modified with MCP-1 peptide to prepare MPF127-MCP-1 (MPM). The DOX was wrapped in MPM to form DMPM nanomicelles (approximately 100 nm) during the self-assembly process of MPM. The DMPM spontaneously bound to macrophages (RAW264.7), which resulted in the construction of an actively targeting delivery system (macrophage-DMPM, MA-DMPM) in vitro and in vivo. The DOX in MA-DMPM was released in the acidic tumor microenvironment (TME) in a pH-responsive manner to increase DOX accumulation and enhance the tumor treatment effect. The ratio of MA-DMPM homing reached 220% in vitro compared with the control group, indicating that the MA-DMPM was excellently capable of tumor-targeting delivery. In in vivo experiments, nonsmall cell lung cancer cell (NCI-H1299) tumor models were established. The results of the fluorescence imaging system (IVIS) showed that MA-DMPM demonstrated tremendous tumor-targeting ability in vivo. The antitumor effects of MA-DMPM in vivo indicated that the proportion of tumor cell apoptosis in the DMPM-treated group was 63.33%. The findings of the tumor-bearing mouse experiment proved that MA-DMPM significantly suppressed tumor cell growth, which confirmed its immense potential and promising applications in tumor therapy.

Enzymatic Reaction-Coupled, Cooperative Supramolecular Polymerization.

Nature employs sophisticated mechanisms to precisely regulate self-assembly and functions within biological systems, exemplified by the formation of cytoskeletal filaments. Various enzymatic reactions and auxiliary proteins couple with the self-assembly process, meticulously regulating the length and functions of resulting macromolecular structures. In this context, we present a bioinspired, reaction-coupled approach for the controlled supramolecular polymerization in synthetic systems. To achieve this, we employ an enzymatic reaction that interfaces with the adenosine triphosphate (ATP)-templated supramolecular polymerization of naphthalene diimide monomers (NSG). Notably, the enzymatic production of ATP (template) plays a pivotal role in facilitating reaction-controlled, cooperative growth of the NSG monomers. This growth process, in turn, provides positive feedback to the enzymatic production of ATP, creating an ideal reaction-coupled assembly process. The success of this approach is further evident in the living-growth characteristic observed during seeding experiments, marking this method as the pioneering instance where reaction-coupled self-assembly precisely controls the growth kinetics and structural aspects of supramolecular polymers in a predictive manner, akin to biological systems.

Exceptional stability of spinel Ni–MgAl2O4 catalyst with ordered mesoporous structure for dry reforming of methane

The dry reforming of methane reaction holds significant importance for the comprehensive utilization of CO2 and CH4, contributing to carbon neutrality. However, due to the high reaction temperatures, catalyst deactivation due to carbon deposition and sintering remains a challenge. In this study, a one-pot method was employed to improve the solvent evaporation self-assembly process for the preparation of Ni–MgAl2O4 catalysts. The impact of calcination temperature (600 °C, 800 °C, and 1000 °C) on the ordered mesoporous structure of the catalyst was investigated. Catalysts without an ordered mesoporous structure, such as Ni–MgAl2O4-1000, suffered deactivation due to carbon deposition caused by the large size of Ni grains, while Ni–MgAl2O4-600 deactivated due to sintering caused by the lack of confinement effect of the support on Ni. Conversely, Ni–MgAl2O4 catalysts with an ordered mesoporous structure exhibited confinement effects on Ni metal, resulting in excellent resistance to carbon deposition and sintering. Further investigation into the effect of different loading methods of Ni on methane dry reforming was conducted. A comparison was made between Ni–MgAl2O4 (800 °C) prepared by the one-pot method and Ni/MgAl2O4 (800 °C) prepared by the impregnation method. It was observed that Ni–MgAl2O4 catalysts, with Ni incorporated into the support, exhibited strong interaction between Ni and the support. During a 500-h long-term reaction, both CO2 and CH4 conversion rates remained at 90% for Ni–MgAl2O4 catalysts, with less carbon deposition and slower grain growth rate, demonstrating excellent reaction activity and stability. In contrast, the performance of Ni/MgAl2O4 catalysts gradually declined after 260 h. Ni–MgAl2O4 catalysts with ordered mesopores and strong interaction between Ni and the support displayed superior resistance to carbon deposition and sintering.

Fluoride-Ion-Responsive Sol-Gel Transition in an L-Cysteine/AgNO3 System: Self-Assembly Peculiarities and Anticancer Activity.

Supramolecular hydrogels based on low-molecular-weight compounds are a unique class of so-called "soft" materials, formed by weak non-covalent interactions between precursors at their millimolar concentrations. Due to the variety of structures that can be formed using different low-molecular-weight gelators, they are widely used in various fields of technology and medicine. In this study, we report for the first time an unusual self-assembly process of mixing a hydrosol obtained from L-cysteine and silver nitrate (cysteine-silver sol-CSS) with sodium halides. Modern instrumental techniques such as viscosimetry, UV spectroscopy, dynamic light scattering, zeta potential measurements, SEM and EDS identified that adding fluoride anions to CSS is able to form stable hydrogels of a thixotropic nature, while Cl-, Br- and I- lead to precipitation. The self-assembly process proceeds using a narrow concentration range of F-. An increase in the fluoride anion content in the system leads to a change in the gel network morphology from elongated structures to spherical ones. This fact is reflected in a decrease in the gel viscosity and a number of gel-sol-gel transition cycles. The mechanism of F-'s interaction with hydrosol includes the condensation of anions on the positive surface of the CSS nanoparticles, their binding via electrostatic forces and the formation of a resulting gel carcass. In vitro analysis showed that the hydrogels suppressed human squamous carcinoma cells at a micromolar sample concentration. The obtained soft gels could have potential applications against cutaneous malignancy and as carriers for fluoride anion and other bioactive substance delivery.

Investigation on sacrificial hydrolysis reaction of octadecyltrimethoxysilane for moisture resistance enhancement of metal–organic framework

Imparting water resistance is important for structures which is vulnerable to moisture to maintain the performance. In this study, octadecyltrimethoxysilane (ODTMS), which forms a hydrophobic surface through polymerization on the surface of the material, was used to enhance the hydrophobicity of HKUST-1 (HHK-x). This self-assembled structure reacts as sacrificial barrier to continuously penetrating H2O molecules and this effect is evaluated with detection of O–H peak (3323 cm−1) in FT-IR spectra. The gas adsorption performance is conducted with CO2 gas and the adsorption amount was reduced by 20 % (from 5.77 to 4.62 mmol/g at 25 °C, 1 bar) compared with the pristine HKUST-1 following the trend of specific surface area. However, water adsorption amount was reduced by 50.2 %, which is 2.5 times higher than the decrease in CO2 adsorption capacity. In addition, when the N2 adsorption and cycle adsorption performances were compared after exposing the sample to air for five days, it was confirmed that HHK-40 maintained its microporous structure and stable performance. The manufactured materials exhibited higher durability in a cyclic vapor sorption test depending on the loading amount of ODTMS and exhibits different tendency depending on the rate of humidity. These results experimentally indicate that accessible self-assembly process of ODTMS on water-vulnerable materials to be sustainable and stable in humid air conditions.

Two-dimensional MXene/MOFs heterojunction nanosheets as confinement hosts for dendrite-free lithium metal anodes

Although metallic lithium is regarded as the most potential anode candidate for next-generation batteries, its applications are greatly restricted by the uncontrollable growth of lithium dendrites and unstable anode/electrolyte interface. Herein, MXene/MOFs heterojunction nanosheets are developed through a convenient self-assembly process by harnessing the chemical interactions between MXene and Ni-MOFs monolayers. In this heterojunction, not only the MXene interlayer induces uniform lithium nucleation, but also MOFs monolayers act as stable interfaces to promote Li ion transport and homogenize the subsequent lithium deposition. Moreover, the MXene/MOFs substrate mitigates the volume change of lithium anodes. Consequently, 2D MXene/MOFs heterojunction nanosheets as confinement hosts effectively suppress lithium dendrites and exhibit enhanced electrochemical performances including a coulombic efficiency of 99 % over 300 cycles at 0.5 mA cm−2 and 1 mAh cm−2, and a long cycling life up to 500 h at 1 mA cm−2 and 1 mAh cm−2. The MXene/MOFs-Li||LiFePO4 cells exhibit a stable cycling performance with a capacity retention of 91 % after 600 cycles.

Metal-organic framework/MXene nanohybrid composites as an emerging electrochemical sensing platform for food safety and biomedical monitoring: From synthesis to application

Metal-organic frameworks (MOFs) are created through the self-assembly process of metal ions or clusters with organic linkers. These materials have attracted important interest owing to their advantageous features, comprising abundant pore structures, ultrahigh porosity, and well-exposed active sites. However, some traditional MOFs have limitations in terms of low stability and conductivity. Despite significant endeavors to enhance the stability of MOF materials, limited advancement has prompted researchers to concentrate on the development of hybrid materials. MXenes, a group of 2D transition-metal compounds comprising nitrides, carbides, and carbonitrides, are recognized for their diverse composition and their ability to form various buildings with rich surface chemistry. The hybridization of MOFs with functional MXene layered could be advantageous if the host structure offers suitable interactions to enhance and stabilize the desired features. Current research has concentrated on incorporating MXenes and MOFs to generate nanohybrid materials with boosted electrochemical features, thus broadening the scope for new applications. This review explores potential design approaches for MXene@MOF nanohybrids, the tunable characteristics of the resulting hybrids, and their use in electrochemical sensing platforms for food safety and biomedical monitoring. Finally, the authors discuss the challenges and future opportunities of MOF@MXene-derived nanocomposites.

Crystallization-Inspired Design and Modeling of Self-Assembly Lattice-Formation Swarm Robotics.

Self-assembly formation is a key research topic for realizing practical applications in swarm robotics. Due to its inherent complexity, designing high-performance self-assembly formation strategies and proposing corresponding macroscopic models remain formidable challenges and present an open research frontier. Taking inspiration from crystallization, this paper introduces a distributed self-assembly formation strategy by defining free, moving, growing, and solid states for robots. Robots in these states can spontaneously organize into user-specified two-dimensional shape formations with lattice structures through local interactions and communications. To address the challenges posed by complex spatial structures in modeling a macroscopic model, this work introduces the structural features estimation method. Subsequently, a corresponding non-spatial macroscopic model is developed to predict and analyze the self-assembly behavior, employing the proposed estimation method and a stock and flow diagram. Real-robot experiments and simulations validate the flexibility, scalability, and high efficiency of the proposed self-assembly formation strategy. Moreover, extensive experimental and simulation results demonstrate the model's accuracy in predicting the self-assembly process under different conditions. Model-based analysis indicates that the proposed self-assembly formation strategy can fully utilize the performance of individual robots and exhibits strong self-stability.

Furan-based AIE supramolecular self-assembly system for fluorescence detection of Ag+

A novel furan-based Aggregation-Induced Emission (AIE) supramolecular self-assembling gelator (BM) was designed and synthesized, which could self-assemble into a stable supramolecular gel (OBM) in the 1,2-propanediol. OBM demonstrates “turn-off” fluorescence detection of Ag+, with excellent selectivity and a low limit of detection (LOD) of 1.168×10−8 M. The self-assembly process and ion recognition sensing mechanism of OBM were comprehensively investigated by Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray Photoelectron Spectroscopy (XPS), and rheological measurements. More importantly, single crystal were successfully obtained to validate the self-assembly process. This study provides a novel approach to constructing a multifunctional AIE self-assembly system.

The self-assembly of water reverse micelles with imidazolium ionic liquids in supercritical carbon dioxide: A molecular dynamics simulation study

Molecular dynamics (MD) simulations were employed to investigate the self-assembly of water reverse micelles (RMs) with imidazolium ionic liquids (ILs) stabilized by dodecyl polyoxyethylene (3) polyoxypropylene (6) ether (LS-36) in supercritical carbon dioxide (scCO2) at 308 K and 20 MPa. The study explored the impact of various factors, including the IL concentration, the alkyl chain length of the imidazolium cations (1-ethyl-3-methylimidazolium [EMIM]+, 1-octyl-3-methylimidazolium [OMIM]+), and the anion type (bis(trifluoromethylsulfonyl)imide [NTf2]-, tetrafluoroborate [BF4]-, acetate [ACE]-) on the solubilization of ILs by water reverse micelles. The findings revealed that water, ILs, and the surfactant formed spherical RMs in the fluid phase, with varying structures depending on the hydrophobicity of the IL. The presence of ILs was found to expedite the self-assembly process and increase the number of assembled surfactants. Higher IL concentrations resulted in greater water content in the polar core of the RMs and reduced water solubility in scCO2. The intermolecular interactions occurring between components of the systems as well as dynamical properties are discussed in terms of radial distribution functions, density distribution, hydrogen bond number and lifetime, number of contacts, and self-diffusion coefficients.

Self-Assembled Conjugated Coordination Polymer Nanorings: Role of Morphology and Redox Sites for the Alkaline Electrocatalytic Oxygen Evolution Reaction.

Electrocatalytic water splitting provides a sustainable method for storing intermittent energies, such as solar energy and wind, in the form of hydrogen fuel. However, the oxygen evolution reaction (OER), constituting the other half-cell reaction, is often considered the bottleneck in overall water splitting due to its slow kinetics. Therefore, it is crucial to develop efficient, cost-effective, and robust OER catalysts to enhance the water-splitting process. Transition-metal-based coordination polymers (CPs) serve as promising electrocatalysts due to their diverse chemical architectures paired with redox-active metal centers. Despite their potential, the rational use of CPs has faced obstacles including a lack of insights into their catalytic mechanisms, low conductivity, and morphology issues. Consequently, achieving success in this field requires the rational design of ligands and topological networks with the desired electronic structure. This study delves into the design and synthesis of three novel conjugated coordination polymers (CCPs) by leveraging the full conjugation of terpyridine-attached flexible tetraphenylethylene units as electron-rich linkers with various redox-active metal centers [Co(II), Ni(II), and Zn(II)]. The self-assembly process is tuned for each CCP, resulting in two distinct morphologies: nanosheets and nanorings. The electrocatalytic OER performance efficiency is then correlated with factors such as the nanostructure morphology and redox-active metal centers in alkaline electrolytes. Notably, among the three morphologies studied, nanorings for each CCP exhibit a superior OER activity. Co(II)-integrated CCPs demonstrate a higher activity between the redox-active metal centers. Specifically, the Co(II) nanoring morphology displays exceptional catalytic activity for OER, with a lower overpotential of 347 mV at a current density of 10 mA cm-2 and small Tafel slopes of 115 mV dec-1. The long-term durability is demonstrated for at least 24 h at 1.57 V vs RHE during water splitting. This is presumably the first proof that links the importance of nanostructure morphologies to redox-active metal centers in improving the OER activity, and it may have implications for other transdisciplinary energy-related applications.

A nimble strategy for enabling bioderived flame retardants with strikingly enhanced interfacial compatibility in poly (lactic acid) composites

The utilization of bioderived flame retardants in biodegradable poly (lactic acid) (PLA) has profound practical implications for extending the widespread application of PLA composites and protecting the environment. Nevertheless, there are still certain challenges that require prompt attention, especially the ineffectiveness of bio-based flame retardants and their deterioration of the mechanical properties of PLA. This work introduced triglycidyl isocyanurate (TGIC), which has multiple epoxy functions, into the self-assembly process of phytic acid (PA) and chitosan (CS). The epoxy-modified bioderived flame retardant PA@CS-TGIC (PCT) was well dispersed in the PLA matrix and had a strong interfacial adhesion, while also TGIC had a synergistic char-forming effect. By compounding epoxy-modified ammonium polyphosphate (MAPP), 3%PCT/MAPP-PLA composites may reach a LOI value of 28.8 % and UL-94 V-0 rating. Simultaneously, the melting droplets had been considerably reduced. Tensile strength of the 3%PCT/MAPP-PLA composites was 67.0 MPa, 10.8 % higher than that of pure PLA. This work paves a new avenue for the development of PLA composites with robust mechanical and flame retardant properties.

Study on 2D Molecular Networks of Flexible Pentacarboxylic Acid Ligands Induced by Ether Bonds in Response to Selective Guest Inclusion.

The flexibility of ligands allows for their bending, twisting, or rotation to adopt various conformations, leading to distinct symmetries during the self-assembled process. Flexible aromatic acid ligands modified by ether bonds are a promising type of self-assembled module when it comes to surfaces. Here, two pentacarboxylic acid ligands (H5L1 and H5L2) with minor skeleton differences have successfully self-assembled into disparate porous networks on the graphite surface and demonstrated excellent potential for the inclusion of guest molecules. The H5L1 molecule's network structure only accommodates coronene (COR) molecules. With fewer COR molecules, H5L1 molecules act as a host template to accommodate the COR molecules. When there are too many COR molecules, COR molecules will induce H5L1 molecules to transform into a new host-guest nanostructure. Additionally, H5L2 molecules showed the ability to capture C70 molecules and exhibited cavity selectivity. However, the assembled network of H5L2 was slightly deformed in attempts to trap the COR molecules. To understand these phenomena more deeply, various assembled mechanisms were analyzed in combination with building theoretical models and energy analysis. These results reveal the great potential of flexible aromatic acid ligands in two-dimensional self-assembly and host-guest systems for their application in related fields.

Responsive self-assembly of nanomaterials: Mechanisms, applications, and future perspectives

In the development of nanotechnology, responsive self-assembly has been an important research theme. Responsive self-assembly is a technique where nanoparticles form structures in response to external stimuli like temperature and light. Thermo-responsive and photo-controlled self-assembly processes are outstanding compared with traditional methods, and theyve been applied in drug delivery and smart surfaces. Yet, the two processes still have their own challenges in practical applications. This review explores both techniques for explaining how these external stimuli work and the role of nanomaterial properties in the processes. Then it dives deep into their applications, specifically focusing on their strengths and challenges. Thermo-responsive and photo-controlled self-assembly are eco-friendly and reversible, ensuring their wide applications in various conditions. However, thermo-responsive materials, notably UCST-based polymers, are limited in scope, sensitive to the environment, and extremely expensive, while the effectiveness of the photo-controlled assembly process is limited by certain light conditions. Future research should focus on exploring their potential and overcoming the challenges.

Biomimetic artificial nacre-like microfiber of Co/C modified cellulose nanofiber/Ti3C2Tx MXene with efficient microwave absorption

Although considerable efforts have been made in the fabrication of MXene-based composites for microwave absorption (MA), there is a great challenge to assemble MXene into regularly arranged microfibers prepared by wet-spinning technique for application in the field of MA due to insufficient interlayer interactions between Ti3C2Tx flakes. Heterogeneous interface design by optimizing material components to construct ingenious microstructure is crucial for efficient microwave absorbers. Herein, artificial nacre-like supramolecular microfibers of Co/C modified cellulose nanofiber/Ti3C2Tx MXene (Co/C/CNF/Ti3C2Tx) with plenty of heterogeneous interfaces were prepared by a simple wet-spinning technology through a self-assembly process induced by hydrogen bonding interactions between CNF and Ti3C2Tx. The artificial nacre-like microfibers with layered structure possess abundant heterogeneous interfaces, which facilitate multiple reflections/scattering of electromagnetic waves (EMW) between these interfaces, and at the same time promote interfacial and dipole polarization. The introduction of magnetic Co/C nanoparticles not only offer additional magnetic loss ability and improved impedance matching, but also enhance conductivity loss and polarization loss. Benefiting from these advantages, Co/C/CNF/Ti3C2Tx (1:1:1) fiber exhibits superior MA performance with a minimum reflection loss (RLmin) of up to −62.32 dB (>99.9999 % energy absorption) and a broad effective absorption bandwidth (EAB) of 5.86 GHz. The work provides a promising method for the preparation of biomimetic artificial nacre-like MXene-based microfibers with efficient MA performance, which is expected to be applied in the field of flexible wearable electromagnetic protection.

Interfacial Engineering of Ti3C2Tx MXene Electrode Using g-C3N4 Nanosheets for High-Performance Supercapacitor in Neutral Electrolyte.

The superior performance of the Ti3C2Tx (MXene)-based supercapacitor in acidic electrolytes has recently gained much interest in the energy storage community. Nevertheless, its performance in most neutral electrolytes is unfavorably low, plausibly due to limited ion diffusion between the MXene layers. Herein, protonated g-C3N4 (pg-C3N4) is incorporated into the Ti3C2Tx electrode by using a facile self-assembling process and annealing, which results in increased interlayer d-spacing and electrical conductivity of the composite electrode. As a result, the annealed Ti3C2Tx/pg-C3N4 film revealed an enhanced ion-accessibility and gravimetric capacitance of 140 F g-1 in 1 M aqueous MgSO4 electrolyte. The cyclic stability test also indicates excellent capacitance retention, with negligible loss of capacitance over 10000 cycles.

Efficient visible light-driven Photodegradation of malachite green dye using carbon quantum dots-MXene nanocomposite: Synthesis, characterization, and performance evaluation

BackgroundRemoval of azo dyes is one of important issue in water treatment studies and many of research works focused on it. Current work represents a simple and economical feasible to synthesize carbon quantum dots (CQDs) integrated with Ti3C2(OH)2 MXene nanocomposite (CQDs/MXene) for rapid photodegradation of Malachite green (MG) under visible light irradiation. In practice, CQDs were synthesized via a hydrothermal method from Petroselinum crispum leaves, while Ti3C2(OH)2 nanosheets resulted from a simple etching process of Ti3AlC2 using an alkaline solution (KOH with a trace amount of water). MethodsSubsequently, nanocomposites (CQDs/MXene) were prepared by a self-assembly process through sonication-assisted mixing process under ambient conditions. The prepared catalysts were characterized using various analyses like analysis employing field-emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), and an energy dispersion X-ray (EDX) spectrometer to determine the chemical composition. The optimum measurement of this activity of the CQDs/MXene was attained through adjusting several constraints such as pH, dye concentration, amount of temperature and photocatalyst. Significant findingsThe kinetics of the degradation process were represented using the Langmuir–Hinshelwood model, with a rate constant (k) of 0.1382 min−1. This means that the degradation of MG dye follows a first-order reaction with respect to the dye concentration. In addition, the study also looked at the reusability of the prepared CQDs/MXene nanophotocatalyst and found that it exhibited outstanding stability after three reaction cycles. This suggests that the nanophotocatalyst is a promising material for efficient and sustainable degradation of MG dye. The nanocomposite displays high photocatalytic activity with the ability to reduce 96.1 % of the MG dye concentration after being exposed to 25 min of visible light.

Manufacturing process of liposomal Formation: A coarse-grained molecular dynamics simulation

A method of producing liposomes has been previously developed using a continuous manufacturing technology that involves a co-axial turbulent jet in co-flow. In this study, coarse-grained molecular dynamics (CG-MD) simulations were used to gain a deeper understanding of how the self-assembly process of liposomes is affected by the material attributes (such as the concentration of ethanol) and the process parameters (such as temperature), while also providing detailed information on a nano-scale molecular level. Specifically, the CG-MD simulations yield a comprehensive internal view of the structure and formation mechanisms of liposomes containing DPPC, DPPG, and cholesterol molecules. The importance of this work is that structural details on the molecular level are proposed, and such detail is not possible to obtain through experimental studies alone. The assessment of structural properties, including the area per lipid, diffusion coefficient, and order parameters, indicated that a thicker bilayer was observed at higher ethanol concentrations, while a thinner bilayer was present at higher temperatures. These conditions led to more water penetrating the interior of the bilayer and an unstable structure, as indicated by a larger contact area between lipids and water, and a higher coefficient of lipid lateral diffusion. However, stable liposomes were found through these evaluations at lower ethanol concentrations and/or lower process temperatures. Furthermore, the CG-MD model was further compared and validated with experimental and computational data including liposomal bilayer thickness and area per lipid measurements.

Understanding self-assembly mechanisms in supramolecular fiber materials through multiscale simulation

Supramolecular materials, assembled through non-covalent interactions, have emerged as a versatile and tunable platform for the development of advanced functional materials with tailored properties and applications. However, comprehending the interactions between self-assembled monomers at the molecular level, particularly when organized into fibrous structures, remains a considerable challenge. In this study, we discovered that solely relying on all-atomistic molecular dynamics simulations is insufficient to reproduce the self-assembly process and the formation of fibrous supramolecular structures. Thus, we combined dissipative particle dynamics (DPD) and all-atomistic molecular dynamic simulations to accurately simulate the fibrous supramolecular structures previously observed in experiments. These structures consist of benzene-1,3,5-tricarboxamide (BTA-EG4), 2-ureido-4 [1H]-pyrimidinone-ethylene glycol molecules (UPy-EG), and glycyrrhizic acid (GA) molecules, each exhibiting varying degrees of topology and planarity. Our analyses focused on elucidating the stability mechanism of these fibrous structures. Notably, we found that hydrogen bonds, π-π interactions and nonbonded interactions, especially Coulomb interaction between monomers and water molecules, play pivotal roles in stabilizing these fibrous structures. This study significantly contributes to our understanding of self-assembly mechanism in supramolecular fiber materials and opens avenues for extending this knowledge to other fibrous supramolecular architectures.