Iterative Screening of Vitamin E-Based Functional Lipid Nanoparticles for mRNA Delivery

Ionizable lipids are crucial for the effective delivery of mRNA by using lipid nanoparticles (LNPs). Endowing ionizable lipids with tailored biological properties could potentially augment the therapeutic efficacy of mRNA-based treatments. Herein, a functional vitamin E (VE)-based lipid library with distinct head groups was designed and synthesized. Due to the presence of VE, these lipids inherently exhibited immunomodulatory properties, including the promotion of cellular uptake, dendritic cells maturation, and antigen presentation. Through iterative optimization of the LNP components and the architecture of ionizable lipids, the correlation between the structure of ionizable lipids and their mRNA delivery efficiency has been established, leading to the finding of the most effective delivery formulation. Benefiting from the high mRNA delivery efficiency and the immunomodulatory function of LNPs themselves, VE-based LNPs have demonstrated complete remission in colon cancer by delivering mIL-12, which offered a beneficial combination with immune checkpoint blockade. The proposed functional LNPs were anticipated to furnish potential delivery systems for mRNA-based cancer treatments.

The Internal Nanostructure of Lipid Nanoparticles Influences Their Diverse Cellular Uptake Pathways

Lipid nanoparticles have emerged as critical platforms for bioactive agent delivery, with their success in COVID-19 vaccines highlighting the urgent need to address gaps in understanding their biological interactions. Lyotropic liquid crystalline nanoparticles (LLCNPs) represent promising nanocarriers for bioactive agent delivery. In this study, it is revealed for the first time how internal nanostructures of LLCNPs - liposomes, cubosomes, hexosomes, and micellar cubosomes - influence their cellular uptake pathways. By isolating the effects of mesophase while maintaining consistent particle size, charge, and surface coating, it is demonstrated that non-lamellar LLCNPs, particularly cubosomes, significantly enhance cellular uptake via distinct endocytic and non-endocytic mechanisms. These nanoparticles predominantly utilize passive non-endocytic pathways, such as membrane fusion, bypassing endocytic recycling challenges faced by most nanomaterials, including lamellar liposomes. Among active endocytic pathways, macropinocytosis emerges as the dominant route for non-lamellar particles. The findings establish a direct link between LLCNP internal nanostructure and cellular internalization mechanisms, highlighting the critical role of mesophase design in optimizing nanocarrier performance. This knowledge enables the rational engineering of LLCNPs tailored to target specific uptake pathways, facilitating precision delivery for diverse therapeutic applications and addressing key barriers in intracellular drug transport.

Millisecond Phase Transition Kinetics of Lyotropic Liquid Crystalline Nanoparticles Observed by Time-Resolved Small Angle X-ray Solution Scattering

This study investigates the dynamic behavior of lyotropic liquid crystal nanoparticles (LCNPs), which are widely recognized for their applications in drug delivery. By employing nanosecond near-infrared laser pulse-induced temperature jump (T-jump) and time-resolved X-ray solution scattering, the structural dynamics of phase transitions in phytantriol-based cubosomes and hexosomes are revealed. Both cubosome and hexosome LCNPs undergo phase transitions into noncrystalline phases at high temperatures. Their phase transition kinetics, occurring within milliseconds (ms) and involving one intermediate structure, are captured. Additionally, the reverse self-assembly processes of LCNPs were observed, occurring on the timescale of a few hundred ms. To our knowledge, this is the first observation of LCNP T-jump induced phase transitions on the ms timescale and their reverse self-assembly. These findings provide valuable insights into the LCNP phase transition processes, with potential implications for drug delivery applications.

Design of Functional Gyroid Minimal Surfaces Transporting Proton Based Solely on Surface Hopping Conduction Mechanism

Surface proton hopping conduction (SPHC) mechanisms is an important proton conduction mechanism in conventional polymer electrolytes, along with the Grotthuss and vehicle mechanisms. Due to the small diffusion coefficient of protons in the SPHC mechanism, few studies have focused on the SPHC mechanism. Recently, it has been found that a dense alignment of SO3 - groups significantly lowers the activation energy in the SPHC mechanism, enabling fast proton conduction. In this study, a series of polymerizable amphiphilic-zwitterions is prepared, forming bicontinuous cubic liquid-crystalline assemblies with gyroid symmetry in the presence of suitable amounts of bis(trifluoromethanesulfonyl) imide (HTf2N) and water. In situ polymerization of these compounds yields gyroid-nanostructured polymer films, as confirmed by synchrotron small-angle X-ray scattering experiments. The high proton conductivity of the films on the order of 10-2 S cm-1 at 40 °C and relative humidity of 90% is based solely on the SPHC mechanism.

Tracking Microenvironmental Response on Self-Assembled Phthalocyanine Systems - Adaptive and Non-Adaptive Antibacterial Photosensitization

Self-assembly has proven to be one of the effective methods for the formation of nanoscale therapeutics without the need to use nanodelivery systems. Such minimal models of supramolecular systems formed from amphiphilic photosensitizers (PS) have recently emerged as a new class of photoactive systems, providing unique and in some cases superior activities. Although the mechanism of photogenerated reactive oxygen species (ROS) in such systems is studied and to a certain extent understood, there are very limited studies investigating the influence of intricate environmental factors, including those occurring in the cellular environment, on the self-assembly and thus the activity of the system. Understanding the optimal conditions for the formation of active PS aggregates is an important area of research in the field of photodynamic therapy (PDT), as it is directly linked to the optimal treatment dose. In this study, we describe the synthesis, self-assembly properties, photophysical characterization, and photobiological efficacy of structurally closely related low-symmetry phthalocyanine derivatives. Studying the decay behavior of the PS fluorescence lifetime in the presence of molecular crowders and different bacterial strains, we found that certain derivatives exhibited adaptive behavior and change in activity, while others demonstrated non-adaptive characteristics.

Design of V-shaped ionic liquid crystals: atropisomerisation ability and formation of double-gyroid molecular assemblies

We designed V-shaped ionic liquid crystals with two sterically congested ionic parts at the vertex. Depending on the degree of steric hindrance, atropisomerisation occurred in solution. All compounds formed bicontinuous cubic phases with double-gyroid structures in the bulk state, partially owing to the co-existence of atropisomers with opposite chirality.

Evaluation of polymersome permeability as a fundamental aspect towards the development of artificial cells and nanofactories

Polymersomes are synthetic vesicles with potential use in healthcare, chemical transformations in confined environment (nanofactories), and in the construction of artificial cells and organelles. In this framework, one of the most important features of such supramolecular structures is the permeability behavior allowing for selective control of mass exchange between the inner and outer compartments. The use of biological and synthetic nanopores in this regard is the most common strategy to impart permeability nevertheless, this typically requires fairly complex strategies to enable porosity. Yet, investigations concerning the permeability of polymer vesicles to different analytes still requires further exploration and, taking these considerations into account, we have detailed investigated the permeability behavior of a variety of polymersomes with regard to different analytes (water, protons, and rhodamine B) which were selected as models for solvents, ions, and small molecules. Polymersomes based on hydrophilic blocks of poly[N-(2-hydroxypropyl)methacrylamide] (PHPMA) or PEO (poly(ethylene oxide)) linked to the non-responsive blocks poly[N-(4-isopropylphenylacetamide)ethyl methacrylate] (PPPhA) or poly(methyl methacrylate) (PMMA), or to the stimuli pH-responsive block poly[2-(diisopropylamino)ethyl methacrylate] (PDPA) have been investigated. Interestingly, the produced PEO-based vesicles are notably larger than the ones produced using PHPMA-containing block copolymers. The experimental results reveal that all the vesicles are inherently permeable to some extent with permeability behavior following exponential profiles. Nevertheless, polymersomes based on PMMA as the hydrophobic component were demonstrated to be the least permeable to the small molecule rhodamine B as well as to water. The synthetic vesicles based on the pH-responsive PDPA block exhibited restrictive and notably slow proton permeability as attributed to partial chain protonation upon acidification of the medium. The dye permeability was evidenced to be much slower than ion or solvent diffusion, and in the case of pH-responsive assemblies, it was demonstrated to also depend on the ionic strength of the environment. These findings are understood to be highly relevant towards polymer selection for the production of synthetic vesicles with selective and time-dependent permeability, and it may thus contribute in advancing biomimicry and nanomedicine.

Complex Phase Transitions of Fully Rigid Sphere-Rod Amphiphiles Induced by Solvent Polarity in Dilute Solutions

We report complex macrophase and microphase transitions of rigid amphiphiles with spherical Keggin molecular clusters as the solvophilic block and rod-like rigid oligofluorene (OF) as the solvophobic block in mixed solvents of water and polar organic solvent. By properly adjusting the solvent polarity, the amphiphiles are found to respond accordingly by self-assembling into multilayered incomplete onion-like structures (10-25 vol % THF), single-layered vesicular structures (60 vol % THF), and an unexpected macrophase separation in the middle (40-50 vol % THF), which is due to the anomalous trends in Keggin solubility as a result of the nature of TBA+ counterions. The rigidity of the OF block prevents the amphiphile from assembling by following the rule of packing parameters; instead, interdigitation among different rods leads to the formation of the solvophobic domain to achieve self-assembly. The incomplete onion structures are controlled by the interdigitation of rigid rods for the number of layers and the electrostatic interaction among Keggin head groups for the interlayer distance. When the degree of interdigitation becomes lower, the self-assembly process shows a trend that can be explained by the traditional rule of packing parameter. This study demonstrates the formation of different self-assembled structures by rigid amphiphiles and their transitions induced by solvent composition. The self-assembly (microphase separation) of rigid amphiphiles in a dilute solution could indeed represent a broad area containing complicated, uncharted rules.

Toward Ultrahigh Rate and Cycling Performance of Cathode Materials of Sodium Ion Battery by Introducing a Bicontinuous Porous Structure

The emerging sodium-ion batteries (SIBs) are one of the most promising candidates expected to complement lithium-ion batteries and diversify the battery market. However, the exploitation of cathode materials with high-rate performance and long-cycle stability for SIBs has remained one of the major challenges. To this end, an efficient approach to enhance rate and cycling performance by introducing an ordered bicontinuous porous structure into cathode materials of SIBs is demonstrated. Prussian blue analogues (PBAs) are selected because they are recognized as a type of most promising SIB cathode materials. Thanks to the presence of 3D continuous channels enabling fast Na+ ions diffusion as well as the intrinsic mechanical stability of bicontinuous architecture, the resultant PBAs exhibit excellent rate capability (80 mAh g-1 at 2.5 A g-1) and ultralong cycling life (>3000 circulations at 0.5 A g-1), reaching the top performance of the reported PBA-based cathode materials. This study opens a new avenue for boosting sluggish ion diffusion kinetics in electrodes of rechargeable batteries and also provides a new paradigm for solving the dilemma that electrodes' failure due to high-stress concentration upon ion storage.

Co-Assembled Supramolecular Organohydrogels of Amphiphilic Zwitterion and Polyoxometalate with Controlled Microstructures

The organization of modifiable and functional building components into various superstructures is of great interest due to their broad applications. Supramolecular self-assembly, based on rationally designed building blocks and appropriately utilized driving forces, is a promising and widely used strategy for constructing superstructures with well-defined nanostructures and diverse morphologies across multiple length scales. In this study, two homogeneous organohydrogels with distinct appearances were constructed by simply mixing polyoxometalate (phosphomolybdic acid, HPMo) and a double-tailed zwitterionic quaternary ammonium amphiphile in a binary solvent of water and dimethyl sulfoxide (DMSO). The delicate balance between electrostatic attraction and repulsion of anionic HPMo clusters and zwitterionic structures drove them to co-assemble into homogeneous organohydrogels with diverse microstructures. Notably, the morphologies of the organohydrogels, including unilamellar vesicles, onion-like vesicles, and spherical aggregates, can be controlled by adjusting the ionic interactions between the zwitterionic amphiphiles and phosphomolybdic acid clusters. Furthermore, we observed an organohydrogel fabricated with densely stacked onion-like structures (multilamellar vesicles) consisting of more than a dozen layers at certain proportions. Additionally, the relationships between the self-assembled architectures and the intermolecular interactions among the polyoxometalate, zwitterionic amphiphile, and solvent molecules were elucidated. This study offers valuable insights into the mechanisms of polyoxometalate-zwitterionic amphiphile co-assembly, which are essential for the development of materials with specific structures and emerging functionalities.

Small-angle X-ray and neutron scattering applied to lipid-based nanoparticles: Recent advancements across different length scales

Lipid-based nanoparticles (LNPs), ranging from nanovesicles to non-lamellar assemblies, have gained significant attention in recent years, as versatile carriers for delivering drugs, vaccines, and nutrients. Small-angle scattering methods, employing X-rays (SAXS) or neutrons (SANS), represent unique tools to unveil structure, dynamics, and interactions of such particles on different length scales, spanning from the nano to the molecular scale. This review explores the state-of-the-art on scattering methods applied to unveil the structure of lipid-based nanoparticles and their interactions with drugs and bioactive molecules, to inform their rational design and formulation for medical applications. We will focus on complementary information accessible with X-rays or neutrons, ranging from insights on the structure and colloidal processes at a nanoscale level (SAXS) to details on the lipid organization and molecular interactions of LNPs (SANS). In addition, we will review new opportunities offered by Time-resolved (TR)-SAXS and -SANS for the investigation of dynamic processes involving LNPs. These span from real-time monitoring of LNPs structural evolution in response to endogenous or external stimuli (TR-SANS), to the investigation of the kinetics of lipid diffusion and exchange upon interaction with biomolecules (TR-SANS). Finally, we will spotlight novel combinations of SAXS and SANS with complementary on-line techniques, recently enabled at Large Scale Facilities for X-rays and neutrons. This emerging technology enables synchronized multi-method investigation, offering exciting opportunities for the simultaneous characterization of the structure and chemical or mechanical properties of LNPs.

pH-Dependent Lyotropic Liquid Crystalline Mesophase and Ionization Behavior of Phytantriol-Based Ionizable Lipid Nanoparticles

Self-assembled lipid nanoparticles (LNPs), serving as essential nanocarriers in recent COVID-19 mRNA vaccines, provide a stable and versatile platform for delivering a wide range of biological materials. Notably, LNPs with unique inverse mesostructures, such as cubosomes and hexosomes, are recognized as fusogenic nanocarriers in the drug delivery field. This study delves into the physicochemical properties, including size, lyotropic liquid crystalline mesophase, and apparent pKa of LNPs with various lipid components, consisting of two ionizable lipids (ALC-0315 and SM-102) used in commercial COVID-19 mRNA vaccines and a well-known inverse mesophase structure-forming helper lipid, phytantriol (PT). Two partial mesophase diagrams are generated for both ALC-0315/PT LNPs and SM-102/PT LNPs as a function of two factors, ionizable lipid ratio (α, 0-100 mol%) and pH condition (pH 3-11). Furthermore, the impact of different LNP stabilizers (Pluronic F127, Pluronic F108, and Tween 80) on their pH-dependent phase behavior is evaluated. The findings offer insights into the self-assembled mesostructure and ionization state of the studied LNPs with potentially enhanced endosomal escape ability. This research is relevant to developing innovative next-generation LNP systems for delivering various therapeutics.

Increasing the Accessibility of Internal Catalytic Sites in Covalent Organic Frameworks by Introducing a Bicontinuous Mesostructure

Introducing continuous mesochannels into covalent organic frameworks (COFs) to increase the accessibility of their inner active sites has remained a major challenge. Here, we report the synthesis of COFs with an ordered bicontinuous mesostructure, via a block copolymer self-assembly-guided nanocasting strategy. Three different mesostructured COFs are synthesized, including two covalent triazine frameworks and one vinylene-linked COF. The new materials are endowed with a hierarchical meso/microporous architecture, in which the mesochannels exhibit an ordered shifted double diamond (SDD) topology. The hierarchically porous structure can enable efficient hole-electron separation and smooth mass transport to the deep internal of the COFs and consequently high accessibility of their active catalytic sites. Benefiting from this hierarchical structure, these COFs exhibit excellent performance in visible-light-driven catalytic NO removal with a high conversion percentage of up to 51.4 %, placing them one of the top reported NO-elimination photocatalysts. This study represents the first case of introducing a bicontinuous structure into COFs, which opens a new avenue for the synthesis of hierarchically porous COFs and for increasing the utilization degree of their internal active sites.

Nanotechnology strategies to address challenges in topical and cellular delivery of siRNAs in skin disease therapy

Gene therapy is one of the most advanced therapies in current medicine. In particular, interference RNA-based therapy by small interfering RNA (siRNA) has gained attention in recent years as it is a highly versatile, selective and specific therapy. In dermatological conditions, topical delivery of siRNA offers numerous therapeutic advantages, mainly by inhibiting the expression of target transcripts directly in the skin. However, crossing the stratum corneum and overcoming intracellular barriers is an inherent challenge. Substantial efforts by scientists have moved towards the use of multimodal and multifunctional nanoparticles to overcome these barriers and achieve greater bioavailability in their site of action, the cytoplasm. In this review the most innovative strategies based on nanoparticle and physical methods are presented, as well as the design principles and the main factors that contribute to the performance of these systems. This review also highlights the synergistic contributions of medicine, nanotechnology, and molecular biology to advancing translational research into siRNA-based therapeutics for skin diseases.

The influence of mannose-based esters on the mesophase behaviour of lyotropic liquid crystalline nanosystems as drug delivery vectors

Lyotropic Liquid Crystalline (LLC) nanoparticles represent an emerging class of smart, biocompatible, and biodegradable systems for the delivery of drugs. Among these, structures with complex 3D architectures such as cubosomes are of particular interest. These are non- lamellar assemblies having hydrophobic and hydrophilic portions able to carry drugs of different nature. They can further be modulated including suitable additives to control the release of the active payload, and to promote an active targeting. Starting from monoolein (GMO) cubic phase, different concentrations of mannose-based esters were added, and the eventual structural modifications were monitored to ascertain the effects of the presence of glycolipids. Moreover, the structural properties of these nanosystems loaded with Dexamethasone (DEX), a very well-known anti-inflammatory steroid, were also studied. Experiments were carried out by synchrotron Small Angle X-ray Scattering (SAXS), Raman Microspectroscopy (RMS) and Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) measurements. The drug delivery potential (i.e. entrapment efficiency and release properties) of the obtained nanoparticles was evaluated. Finally, in vitro cytocompatibility and anti-inflammatory activity studies of the prepared formulations were carried out. Inclusion of mannose-based surfactants up to 10 mol% influenced the structural parameters of Im3m cubic phase and swollen cubic phases were obtained with the different glycolipids with lattice parameters significantly higher than GMO. A complete cytocompatibility and an increased DEX activity were observed, thus suggesting the possibility to use GMO/glycolipids nanoparticles to formulate innovative drug delivery systems.

Lyotropic liquid crystalline 2D and 3D mesophases: Advanced materials for multifunctional anticancer nanosystems

Cancer remains a leading cause of mortality. Despite significant breakthroughs in conventional therapies, treatment is still far from ideal due to high toxicity in normal tissues and therapeutic inefficiency caused by short drug lifetime in the body and resistance mechanisms. Current research moves towards the development of multifunctional nanosystems for delivery of chemotherapeutic drugs, bioactives and/or radionuclides that can be combined with other therapeutic modalities, like gene therapy, or imaging to use in therapeutic screening and diagnosis. The preparation and characterization of Lyotropic Liquid Crystalline (LLC) mesophases self-assembled as 2D and 3D structures are addressed, with an emphasis on the unique properties of these nanoassemblies. A comprehensive review of LLC nanoassemblies is also presented, highlighting the most recent advances and their outstanding advantages as drug delivery systems, including tailoring strategies that can be used to overcome cancer challenges. Therapeutic agents loaded in LLC nanoassemblies offer qualitative and quantitative enhancements that are superior to conventional chemotherapy, particularly in terms of preferential accumulation at tumor sites and promoting enhanced cancer cell uptake, lowering tumor volume and weight, improving survival rates, and increasing the cytotoxicity of their loaded therapeutic agents. In terms of quantitative anticancer efficacy, loaded LLC nanoassemblies reduced the IC50 values from 1.4-fold against lung cancer cells to 125-fold against ovarian cancer cells.

PNIPAM-stabilized cubosomes as fusogenic delivery nanovectors for anticancer applications

In recent years, lipid cubic nanoparticles have emerged as promising nanocarriers for drug delivery, due to the several advantages they exhibit with respect to other lipid systems. Here, we report on lipid cubic nanoparticles stabilized by PNIPAM-based amphiphilic block copolymers, specifically, poly(N, N-dimethylacrylamide)-block-poly(N-isopropylacrylamide) (PDMA-b-PNIPAM), as a new class of drug delivery systems (DDS). In vitro studies on the internalization efficiency of the DDS towards two types of human cancer cells (colon HCT-116 and bladder T24 cells), carried out employing a set of sensitive techniques (confocal laser scanning microscopy (CLSM), flow cytometry, scanning electron microscopy (SEM), fluorescence spectroscopy), highlight a prominent role of PDMA-b-PNIPAM stabilizer in enhancing the uptake of cubosomes, compared to the standard Pluronic F127-based formulations. The drug delivery potential of cubosomes, tested by encapsulating a chemotherapeutic drug, camptothecin (CPT), and conducting cytotoxicity studies against 2D plated cells and 3D spheroids, confirm that PDMA-b-PNIPAM-stabilized cubosomes improve the efficacy of treatment with CPT. The origin of this effect lies in the higher lipophilicity of the stabilizer, as we confirm by studying the interaction between the cubosomes and biomimetic membranes of lipid vesicles with Small Angle X-Ray Scattering (SAXS) and CLSM experiments. These results corroborate our fundamental understanding of the interaction between cubosomes and cells, and on the role of polymer to formulate lipid cubic nanoparticles as DDS.

Inverse Cubic and Hexagonal Mesophase Evolution within Ionizable Lipid Nanoparticles Correlates with mRNA Transfection in Macrophages

mRNA lipid nanoparticle (LNP) technology presents enormous opportunities to prevent and treat various diseases. Here, we developed a novel series of LNPs containing ionizable amino-lipids showing a remarkable array of tunable and pH-sensitive lyotropic liquid crystalline mesophases including the inverse bicontinuous cubic and hexagonal phases characterized by high-throughput synchrotron radiation X-ray scattering. Furthermore, with an interest in developing mRNA therapeutics for lung macrophage targeting, we discovered that there is a strong correlation between the mesophase transition of the LNPs during acidification and the macrophage association/transfection efficiency of mRNAs. The slight molecular structural differences between the SM-102 and ALC-0315 ionizable lipids are linked to the LNP's ability to transform their internal structures from an amorphous state to the inverse micellar, hexagonal, and finally cubic structures during endosomal maturation. SM-102 LNPs showed exceptionally improved transfection efficiency due to their ability to form a cubic structure at a lower pH than the ALC-0315 analogues, which remained within the hexagonal structure, previously attributed to promoting endosomal escape of the ionizable LNPs. Overall, the new knowledge draws our attention to the important role of mesophase transition in endosomal escape, and the novel LNP libraries reported herein have broad prospects for advancing mRNA therapeutics.

Coencapsulation of Gemcitabine and Thymoquinone in Citrem-Phosphatidylcholine Hexosome Nanocarriers Improves In Vitro Cellular Uptake in Breast Cancer Cells

Lyotropic liquid crystalline nanoassemblies (LLCNs) are internally self-assembled (ISA)-somes formed by amphiphilic molecules in a mixture comprising a lipid, stabilizer, and/or surfactant and aqueous media/dispersant. LLCNs are unique nanoassemblies with versatile applications in a wide range of biomedical functions. However, they comprise a nanosystem that is yet to be fully explored for targeted systemic treatment of breast cancer. In this study, LLCNs proposed for gemcitabine and thymoquinone (Gem-TQ) co-delivery were prepared from soy phosphatidylcholine (SPC), phytantriol (PHYT), or glycerol monostearate (MYVR) in optimized ratios containing a component of citric and fatty acid ester-based emulsifier (Grinsted citrem) or a triblock copolymer, Pluronic F127 (F127). Hydrodynamic particle sizes determined were below 400 nm (ranged between 96 and 365 nm), and the series of nanoformulations displayed negative surface charge. Nonlamellar phases identified by small-angle X-ray scattering (SAXS) profiles comprise the hexagonal, cubic, and micellar phases. In addition, high entrapment efficiency that accounted for 98.3 ± 0.1% of Gem and 99.5 ± 0.1% of TQ encapsulated was demonstrated by the coloaded nanocarrier system, SPC/citrem/Gem-TQ hexosomes. Low cytotoxicity of SPC-citrem hexosomes was demonstrated in MCF10A cells consistent with hemo- and biocompatibility observed in zebrafish (Danio rerio) embryos for up to 96 h postfertilization (hpf). SPC/citrem/Gem-TQ hexosomes demonstrated IC50 of 24.7 ± 4.2 μM in MCF7 breast cancer cells following a 24 h treatment period with the moderately synergistic interaction between Gem and TQ retained (CI = 0.84). Taken together, biocompatible SPC/citrem/Gem-TQ hexosomes can be further developed as a multifunctional therapeutic nanodelivery approach, plausible for targeting breast cancer cells by incorporation of targeting ligands.

Liquid Crystal Materials for Biomedical Applications

Liquid crystal is a state of matter being intermediate between solid and liquid. Liquid crystal materials exhibit both orientational order and fluidity. While liquid crystals have long been highly recognized in the display industry, in recent decades, liquid crystals provide new opportunities into the cross-field of material science and biomedicine due to their biocompatibility, multifunctionality, and responsiveness. In this review, the latest achievements of liquid crystal materials applied in biomedical fields are summarized. The start is made by introducing the basic concepts of liquid crystals, and then shifting to the components of liquid crystals as well as functional materials derived therefrom. After that, the ongoing and foreseeable applications of liquid crystal materials in the biomedical field with emphasis put on several cutting-edge aspects, including drug delivery, bioimaging, tissue engineering, implantable devices, biosensing, and wearable devices are discussed. It is hoped that this review will stimulate ingenious ideas for the future generation of liquid crystal-based drug development, artificial implants, disease diagnosis, health status monitoring, and beyond.

Real-Time pH-Dependent Self-Assembly of Ionisable Lipids from COVID-19 Vaccines and In Situ Nucleic Acid Complexation

Ionisable amino-lipid is a key component in lipid nanoparticles (LNPs), which plays a crucial role in the encapsulation of RNA molecules, allowing efficient cellular uptake and then releasing RNA from acidic endosomes. Herein, we present direct evidence for the remarkable structural transitions, with decreasing membrane curvature, including from inverse micellar, to inverse hexagonal, to two distinct inverse bicontinuous cubic, and finally to a lamellar phase for the two mainstream COVID-19 vaccine ionisable ALC-0315 and SM-102 lipids, occurring upon gradual acidification as encountered in endosomes. The millisecond kinetic growth of the inverse cubic and hexagonal structures and the evolution of the ordered structural formation upon ionisable lipid-RNA/DNA complexation are quantitatively revealed by in situ synchrotron radiation time-resolved small angle X-ray scattering coupled with rapid flow mixing. We found that the final self-assembled structural identity, and the formation kinetics, were controlled by the ionisable lipid molecular structure, acidic bulk environment, lipid compositions, and nucleic acid molecular structure/size. The implicated link between the inverse membrane curvature of LNP and LNP endosomal escape helps future optimisation of ionisable lipids and LNP engineering for RNA and gene delivery.

Therapeutic potential of lipid nanosystems for the treatment of Parkinson's disease

Parkinson's disease (PD) is the second most common neurodegenerative disorder. The degeneration of dopaminergic neurons in the midbrain is primarily responsible for the onset of the disease. The major challenge faced in the treatment of PD is the blood-brain barrier (BBB), which impedes the delivery of therapeutics to targeted locations. To address this issue, lipid nanosystems have been used for the precise delivery of therapeutic compounds in anti-PD therapy. In this review, we will discuss the application and clinical significance of lipid nanosystem in delivering therapeutic compounds for anti-PD treatment. These medicinal compounds include ropinirole, apomorphine, bromocriptine, astaxanthin, resveratrol, dopamine, glyceryl monooleate, levodopa, N-3,4-bis(pivaloyloxy)- dopamine and fibroblast growth factor, which have significant potential to treat PD in the early stage. This review, in a nutshell, will pave the way for researchers to develop diagnostic and potential therapeutic approaches using nanomedicine to overcome the challenges posed by the BBB in delivering therapeutic compounds for PD.

Recent advances in permeable polymersomes: fabrication, responsiveness, and applications

Polymersomes are vesicular nanostructures enclosed by a bilayer-membrane self-assembled from amphiphilic block copolymers, which exhibit higher stability compared with their biological analogues (e.g. liposomes). Due to their versatility, polymersomes have found various applications in different research fields such as drug delivery, nanomedicine, biological nanoreactors, and artificial cells. However, polymersomes prepared with high molecular weight components typically display low permeability to molecules and ions. It hence remains a major challenge to balance the opposing features of robustness and permeability of polymersomes. In this review, we focus on the design and strategies for fabricating permeable polymersomes, including polymersomes with intrinsic permeability, the formation of nanopores in the membrane bilayers by protein insertion, and the construction of stimuli-responsive polymersomes. Then, we highlight the applications of permeable polymersomes in the fields of biomimetic nanoreactors, artificial cells and organelles, and nanomedicine, to underline the challenges in the development of polymersomes as soft matter with biomedical utilities.

A lipid toolbox of sugar alcohol fatty acid monoesters for single-component lipid nanoparticles with temperature-controlled release

This study aimed to prepare single-component LNPs with sugar alcohol fatty acid monoesters for temperature-controlled release. In total, 20 kinds of lipids with a series of sugar alcohol head groups (ethylene glycol, glycerol, erythritol, xylitol and sorbitol) and fatty acyl tails (12:0, 14:0, 16:0 and 18:0) were synthesised via lipase-catalysed esterification. Their physicochemical properties and upper/lower critical solution temperature (LCST/USCT) were analysed. Two groups of mixed lipids, 78 % ethylene glycol lauric acid monoester + 22 % sorbitol stearic acid monoester (LNP-1) and 90 % ethylene glycol lauric acid monoester + 10 % xylitol myristic acid monoester (LNP-2), had LCST/USCT of approximately 37 °C, which formed empty LNPs using the emulsification-diffusion method. These two mixed lipids were prepared for LNPs loaded with curcumin, showing high encapsulation (>90 %), mean particle sizes of approximately 250 nm and low polydispersity index (≤0.2). These lipids have the potential for tailor-made LNPs achieving thermo-responsivity in delivering bioactive agents and drugs.

Effect of Size, Shape and Surface Functionalization on the Antibacterial Activity of Silver Nanoparticles

Silver nanoparticles (AgNPs) are the most investigated antibacterial agents against multidrug resistant (MDR) pathogens. They can lead to cellular death by means of different mechanisms, damaging several cell compartments, from the external membrane, to enzymes, DNA and proteins; this simultaneous attack amplifies the toxic effect on bacteria with respect to traditional antibiotics. The effectiveness of AgNPs against MDR bacteria is strongly correlated with their chemical and morphological properties, which influence the pathways involved in cellular damage. In this review, AgNPs' size, shape and modification by functional groups or other materials are reported, both to investigate the different synthetic pathways correlated with nanoparticles' modifications and to evaluate the related effect on their antibacterial activity. Indeed, understanding the synthetic conditions for obtaining performing antibacterial AgNPs could help to tailor new and improved silver-based agents to combat multidrug resistance.

Formation of particulate lipid lyotropic liquid crystalline nanocarriers using a microfluidic platform

HYPOTHESIS

Non-lamellar lyotropic liquid crystal nanoparticles (LLCNPs) are gaining significant interest in the fields of drug delivery and nanomedicine. Traditional, top-down formulation strategies for LLCNPs are typically low-throughput, can lack controllability and reproducibility in the particle size distribution, and may be unsuitable for loading more fragile therapeutics. The development of a controllable, reproducible, scalable, and high-throughput strategy is urgently needed.

EXPERIMENTS

Monoolein (MO)-based LLCNPs with various stabilizers (F127, F108, and Tween 80) and phytantriol (PT)-F127 cubosomes were produced at various flow conditions via a bottom-up method using a microfluidic platform.

FINDINGS

This simple enabling strategy was used to formulate LLCNPs with lower polydispersity compared to the traditional top-down homogenization method. Significantly, particle size could be quantitatively controlled by varying the overall flow-rate; a scaling law was identified between nanoparticle mean size and the total flow rate (Q) of meansize∼Q^-0.15 for MO cubosomes and meansize∼Q^-0.19 for PT cubosomes (at a fixed flow rate ratio). Effective size control was achieved for a range of cubosome formulations involving different lipids and stabilizers. The formulation of stable, drug-loaded cubosomes with high encapsulation efficiency using this method was exemplified using calcein as a model drug. This work will further promote the utilisation of LLCNPs in nanomedicine and facilitate their clinical translation.

Metal Organic Framework Cubosomes

We demonstrate a general strategy for the synthesis of ordered bicontinuous-structured metal organic frameworks (MOFs) by using polymer cubosomes (PCs) with a double primitive structure (Im 3 ‾ ${\bar{3}}$ m symmetry) as the template. The filling of MOF precursors in the open channel of PCs, followed by their coordination and removal of the template, generates MOF cubosomes with a single primitive topology (Pm 3 ‾ ${\bar{3}}$ m) and average mesopore diameters of 60-65 nm. Mechanism study reveals that the formation of ZIF-8 cubosomes undergoes a new MOF growth process, which involves the formation of individual MOF seeds in the template, their growth and eventual fusion into the cubosomes. Their growth kinetics follows the Avrami equation with an Avrami exponent of n=3 and a growth rate of k=1.33×10^-4 , indicating their fast 3D heterogeneous growth mode. Serving as a bioreactor, the ZIF-8 cubosomes show high loading of trypsin enzyme, leading to a high catalytic activity in the proteolysis of bovine serum albumin.

Characterizing the Self-Assembly Properties of Monoolein Lipid Isosteres

Living cells feature lipid compartments which exhibit a variety of shapes and structures that assist essential cellular processes. Many natural cell compartments frequently adopt convoluted nonlamellar lipid architectures that facilitate specific biological reactions. Improved methods for controlling the structural organization of artificial model membranes would facilitate investigations into how membrane morphology affects biological functions. Monoolein (MO) is a single-chain amphiphile which forms nonlamellar lipid phases in aqueous solution and has wide applications in nanomaterial development, the food industry, drug delivery, and protein crystallization. However, even if MO has been extensively studied, simple isosteres of MO, while readily accessible, have seen limited characterization. An improved understanding of how relatively minor changes in lipid chemical structure affect self-assembly and membrane topology could instruct the construction of artificial cells and organelles for modeling biological structures and facilitate nanomaterial-based applications. Here, we investigate the differences in self-assembly and large-scale organization between MO and two MO lipid isosteres. We show that replacing the ester linkage between the hydrophilic headgroup and hydrophobic hydrocarbon chain with a thioesther or amide functional group results in the assembly of lipid structures with different phases not resembling those formed by MO. Using light and cryo-electron microscopy, small-angle X-ray scattering, and infrared spectroscopy, we demonstrate differences in the molecular ordering and large-scale architectures of the self-assembled structures made from MO and its isosteric analogues. These results improve our understanding of the molecular underpinnings of lipid mesophase assembly and may facilitate the development of MO-based materials for biomedicine and as model lipid compartments.

Interplay of Hydropathy and Heterogeneous Diffusion in the Molecular Transport within Lamellar Lipid Mesophases

Lipid mesophases are being intensively studied as potential candidates for drug-delivery purposes. Extensive experimental characterization has unveiled a wide palette of release features depending on the nature of the host lipids and of the guest molecule, as well as on the environmental conditions. However, only a few simulation works have addressed the matter, which hampers a solid rationalization of the richness of outcomes observed in experiments. Particularly, to date, there are no theoretical works addressing the impact of hydropathy on the transport of a molecule within lipid mesophases, despite the significant fraction of hydrophobic molecules among currently-available drugs. Similarly, the high heterogeneity of water mobility in the nanoscopic channels within lipid mesophases has also been neglected. To fill this gap, we introduce here a minimal model to account for these features in a lamellar geometry, and systematically study the role played by hydropathy and water-mobility heterogeneity by Brownian-dynamics simulations. We unveil a fine interplay between the presence of free-energy barriers, the affinity of the drug for the lipids, and the reduced mobility of water in determining the net molecular transport. More in general, our work is an instance of how multiscale simulations can be fruitfully employed to assist experiments in release systems based on lipid mesophases.

Block Copolymer Self-Assembly Directed Synthesis of Porous Materials with Ordered Bicontinuous Structures and Their Potential Applications

Porous materials with their ordered bicontinuous structures have attracted great interest owing to ordered periodic structures as well as 3D interconnected network and pore channels. Bicontinuous structures may favor efficient mass diffusion to the interior of materials, thus increasing the utilization ratio of active sites. In addition, ordered bicontinuous structures confer materials with exceptional optical and magnetic properties, including tunable photonic bandgap, negative refraction, and multiple equivalent magnetization configurations. The attractive structural advantages and physical properties have inspired people to develop strategies for preparing bicontinuous-structured porous materials. Among a few synthetic approaches, the self-assembly of block copolymers represents a versatile strategy to prepare various bicontinuous-structured functional materials with pore sizes and lattice parameters ranging from 1 to 500 nm. This article overviews progress in this appealing area, with an emphasis on the synthetic strategies, the structural control (including topologies, pore sizes, and unit cell parameters), and their potential applications in energy storage and conversion, metamaterials, photonic crystals, cargo delivery and release, nanoreactors, and biomolecule selection.

Design and Characterization of Lipid-Surfactant-Based Systems for Enhancing Topical Anti-Inflammatory Activity of Ursolic Acid

Skin inflammation is a symptom of many skin diseases, such as eczema, psoriasis, and dermatitis, which cause rashes, redness, heat, or blistering. The use of natural products with anti-inflammatory properties has gained importance in treating these symptoms. Ursolic acid (UA), a promising natural compound that is used to treat skin diseases, exhibits low aqueous solubility, resulting in poor absorption and low bioavailability. Designing topical formulations focuses on providing adequate delivery via application to the skin surface. The aim of this study was to formulate and characterize lipid-surfactant-based systems for the delivery of UA. Microemulsions and liquid crystalline systems (LCs) were characterized by polarized light microscopy (PLM), rheology techniques, and textural and bioadhesive assays. PLM supported the self-assembly of these systems and elucidated their formation. Rheologic examination revealed pseudoplastic and thixotropic behavior appropriate, and assays confirmed the ability of these formulations to adhere to the skin. In vivo studies were performed, and inflammation induced by croton oil was assessed for response to microemulsions and LCs. UA anti-inflammatory activities of ~60% and 50% were demonstrated by two microemulsions and 40% and 35% by two LCs, respectively. These data support the continued development of colloidal systems to deliver UA to ameliorate skin inflammation.

Automation of liquid crystal phase analysis for SAXS, including the rapid production of novel phase diagrams for SDS-water-PIL systems

Lyotropic liquid crystal phases (LCPs) are widely studied for diverse applications, including protein crystallization and drug delivery. The structure and properties of LCPs vary widely depending on the composition, concentration, temperature, pH, and pressure. High-throughput structural characterization approaches, such as small-angle x-ray scattering (SAXS), are important to cover meaningfully large compositional spaces. However, high-throughput LCP phase analysis for SAXS data is currently lacking, particularly for patterns of multiphase mixtures. In this paper, we develop semi-automated software for high throughput LCP phase identification from SAXS data. We validate the accuracy and time-savings of this software on a total of 668 SAXS patterns for the LCPs of the amphiphile hexadecyltrimethylammonium bromide (CTAB) in 53 acidic or basic ionic liquid derived solvents, within a temperature range of 25-75 °C. The solvents were derived from stoichiometric ethylammonium nitrate (EAN) or ethanolammonium nitrate (EtAN) by adding water to vary the ionicity, and adding precursor ions of ethylamine, ethanolamine, and nitric acid to vary the pH. The thermal stability ranges and lattice parameters for CTAB-based LCPs obtained from the semi-automated analysis showed equivalent accuracy to manual analysis, the results of which were previously published. A time comparison of 40 CTAB systems demonstrated that the automated phase identification procedure was more than 20 times faster than manual analysis. Moreover, the high throughput identification procedure was also applied to 300 unpublished scattering patterns of sodium dodecyl-sulfate in the same EAN and EtAN based solvents in this study, to construct phase diagrams that exhibit phase transitions from micellar, to hexagonal, cubic, and lamellar LCPs. The accuracy and significantly low analysis time of the high throughput identification procedure validates a new, rapid, unrestricted analytical method for the determination of LCPs.

Molecular Geometry-Directed Self-Recognition in the Self-Assembly of Giant Amphiphiles

Three sets of polyoxometalate (POM)-based amphiphilic hybrid macromolecules with different rigidity in their organic tails are used as models to understand the effect of molecular rigidity on their possible self-recognition feature during self-assembly processes. Self-recognition is achieved in the mixed solution of two structurally similar, sphere-rigid T-shape-linked oligofluorene(TOF₄ ) rod amphiphiles, with the hydrophilic clusters being Anderson (Anderson-TOF₄ ) and Dawson (Dawson-TOF₄ ), respectively. Anderson-TOF₄ is observed to self-assemble into onion-like multilayer structures and Dawson-TOF₄ forms multilayer vesicles. The self-assembly is controlled by the interdigitation of hydrophobic rods and the counterion-mediated attraction among charged hydrophilic inorganic clusters. When the hydrophobic blocks are less rigid, e.g., partially rigid polystyrene and fully flexible alkyl chains, self-recognition is not observed, attributing to the flexible conformation of hydrophobic molecules in the solvophobic domain. This study reveals that the self-recognition among amphiphiles can be achieved by the geometrical limitation of the supramolecular structure due to the rigidity of solvophobic domains.

Stabilizing Differential Interfacial Curvatures by Mismatched Molecular Geometries: Toward Polymers with Percolating 1 nm Channels of Gyroid Minimal Surfaces

Soft materials with self-assembled networks possess saddle-shaped interfaces with distributed negative Gaussian curvatures. The ability to stabilize such a geometry is critically important for various applications but can be challenging due to the possibly "deficient" packing of the building blocks. This nontrivial challenge has been manifested, for example, by the limited availability of cross-linkable bicontinuous cubic (Q) liquid crystals (LCs), which can be utilized to fabricate compelling polymers with networked nanochannels uniformly sized at ∼1 nm. Here, we devise a facile approach to stabilizing cross-linkable Q mesophases by leveraging the synergistic self-assembly from pairs of scalably synthesized polymerizable amphiphiles. Hybridization of the molecular geometries by mixing significantly increases the propensity of the local deviations in the interfacial curvature specifically required for Q assemblies. "Normal" (type 1) double gyroid LCs possessing 1 nm ionic channels conforming to minimal surfaces can be formulated by simultaneous hydration of the amphiphile mixtures, as opposed to the formation of hexagonal or lamellar mesophases exhibited by the single-amphiphile systems, respectively. Fixation of the bicontinuous network in polymers via radical polymerization has been efficaciously facilitated by the presence of the bifunctional polymerizable groups in one of the employed amphiphiles. High-fidelity lock-in of the ordered continuous 1 nm channels has been unambiguously confirmed by the observation of single-crystal-like diffraction patterns from synchrotron small-angle X-ray scattering and large-area periodicities by transmission electron microscopy. The produced polymeric materials exhibit the required mechanical integrity as well as chemical robustness in a variety of organic solvents that benefit their practical applications for selective transport of ions and molecules.

Enhancing the photoluminescence and cellular uptake of fluorescent carbon nanodots via cubosome lipid nanocarriers

Carbon nanodots (C-dots) have attracted much attention for their use in the fields of bioimaging, drug delivery, and sensing due to their excellent fluorescent and photoluminescent properties, photostability, biocompatibility, and amenability to surface modification. Herein, we report a nanocomposite formulation of C-dots (<5 nm) encapsulated in lipid-based lyotropic liquid crystalline nanoparticles (∼250 nm) via either passive diffusion or electrostatic mechanisms. The physicochemical properties of the nanocomposite formulation including particle size, surface charge, internal cubic nanostructures, and pH-dependent fluorescent properties were characterised. Upon loading of C-dots into lipid nanoparticles, the highly ordered inverse bicontinuous cubic mesophase existed in the internal phase of the nanoparticles, demonstrated by synchrotron small angle X-ray scattering, molecular dynamic simulation and cryogenic transmission electron microscopy. The pH-dependent fluorescent property of the C-dots was modified via electrostatic interaction between the C-dots and cationic lipid nanoparticles, which further enhanced the brightness of C-dots through self-quenching prevention. The cytotoxicity and cellular uptake efficiency of the developed nanocomposites were also examined in an epithelial gastric adenocarcinoma cell line (AGS) and a macrophage cell line (stimulated THP-1). Compared to free C-dots, the uptake and cell imaging potential of the C-dot nanocomposites was significantly improved, by several orders of magnitude as demonstrated by cytoplasmic fluorescent intensities using confocal microscopy. Loading C-dots into mesoporous lipid nanocarriers presents a new way of modifying C-dot physicochemical and fluorescent properties, alternative to direct chemical surface modification, and advances the bioimaging potential of C-dots by enhancing cellular uptake efficiency and converging C-dot light emission.

Obtaining and Characterizing Stable Bicontinuous Cubic Morphologies and Their Nanochannels in Lyotropic Liquid Crystal Membranes

Amphiphilic monomers in polar solvents can self-assemble into lyotropic liquid crystal (LLC) bicontinuous cubic structures under the right composition and temperature conditions. After cross-linking, the resulting polymer membranes with three-dimensional (3D) continuous uniform channels are excellent candidates for filtration applications. Designing such membranes with the desired physical and chemical properties requires molecular-level understanding of the structure, which can be obtained through molecular modeling. However, building molecular models of bicontinuous cubic structures is challenging due to their narrow regime of stability and the difficulty of self-assembly of large unit cells in molecular simulations. We developed a protocol for building stable bicontinuous cubic unit cells involving both parameterization and assembly of the components. We validate the theoretical structure against experimental results for one such LLC monomer and provide insight into the structure missing in experimental data, as well as demonstrate the qualitative nature of water and solute transport through these membranes.

Swollen cubic phases with reduced hardness solubilizing a model fragrance oil as a co-surfactant

Swollen cubic lyotropic ternary phases with Pn3m symmetry and reduced hardness were obtained from a specific binary mixture of cubic phase-forming (phytantriol) and lamellar phase-forming (decaglycerol monooleate) compounds. The microstructures were determined by using a small-angle x-ray scattering technique. The softness and temperature-induced phase transitions were investigated by means of rheology. The incorporation of a surface-active fragrance compound (linalool) at concentrations up to 6 wt. % induced a structural transition toward a softer Im3m bulk cubic phase with longer water channels. Higher linalool concentrations allowed for the spontaneous dispersion of the bulk cubic phase into microscopic particles with a cubic structure (cubosomes).

Development and optimization of amphiphilic self-assembly into nanostructured liquid crystals for transdermal delivery of an antidiabetic SGLT2 inhibitor

The anti-hyperglycemic sodium glucose co-transporter 2 inhibitor Canagliflozin (CFZ) represents a recent antihyperglycemic modality, yet it suffers from low oral bioavailability. The current work aims to formulate CFZ-loaded transdermal nanostructured liquid crystal gel matrix (NLCG) to improve its therapeutic efficiency. Pre-formulation study included the construction of pseudoternary phase diagrams to explore the effect of two conventional amphiphiles against amphiphilic tri-block copolymer in the formulation of NLCG. The influence of different co-solvents was also investigated with the use of monooleine as the oil. Physical characterization, morphological examination and skin permeation were performed for the optimized formulations. The formula of choice was further investigated for skin irritation and chemical stability. Pharmacodynamic evaluation of the successful formula was conducted on hyperglycemic as well as normoglycemic mice. In addition, oral glucose tolerance test was conducted. Results revealed the supremacy of Poloxamer for stabilizing and maximizing liquid crystal gel (LCG) area percentage that reached up to 12.6%. CFZ-NLCG2 isotropic formula showed the highest permeation parameters; maximum flux value of 7460 μg/cm² h and Q₂₄ of 5327 μg/cm². Pharmacodynamic evaluation revealed the superiority of the antihyperglycemic activity of CFZ-NLCG2 in fasting mice and its equivalence in the oral glucose tolerance test (OGTT) compared to the oral one. The obtained results confirmed the success of CFZ-NLCG2 in the transdermal delivery of CFZ in therapeutically effective concentration compared to the oral route, bypassing first pass effect; in addition, eliminates the possible gastrointestinal side effects related to the inhibition of intestinal sodium glucose co-transporter (SGLT) and maximizes its selectivity to the desired inhibition of renal SGLT.

Polyphenol-Functionalized Cubosomes as Thrombolytic Drug Carriers

The safe administration of thrombolytic agents is a challenge for the treatment of acute thrombosis. Lipid-based nanoparticle drug delivery technologies present opportunities to overcome the existing clinical limitations and deliver thrombolytic therapy with enhanced therapeutic outcomes and safety. Herein, lipid cubosomes are examined as nanocarriers for the encapsulation of thrombolytic drugs. The lipid cubosomes are loaded with the thrombolytic drug urokinase-type plasminogen activator (uPA) and coated with a low-fouling peptide that is incorporated within a metal-phenolic network (MPN). The peptide-containing MPN (pep-MPN) coating inhibits the direct contact of uPA with the surrounding environment, as assessed by an in vitro plasminogen activation assay and an ex vivo whole blood clot degradation assay. The pep-MPN-coated cubosomes prepared with 22 wt% peptide demonstrate a cell membrane-dependent thrombolytic activity, which is attributed to their fusogenic lipid behavior. Moreover, compared with the uncoated lipid cubosomes, the uPA-loaded pep-MPN-coated cubosomes demonstrate significantly reduced nonspecific cell association (<10% of the uncoated cubosomes) in the whole blood assay, a prolonged circulating half-life, and reduced splenic uPA accumulation in mice. These studies confirm the preserved bioactivity and cell membrane-dependent release of uPA within pep-MPN-coated lipid cubosomes, highlighting their potential as a delivery vehicle for thrombolytic drugs.

Light-Responsive Molecular Release from Cubosomes Using Swell-Squeeze Lattice Control

Stimuli-responsive materials are crucial to advance controlled delivery systems for drugs and catalysts. Lyotropic liquid crystals (LLCs) have well-defined internal structures suitable to entrap small molecules and can be broken up into low-viscosity dispersions, aiding their application as delivery systems. In this work, we demonstrate the first example of light-responsive cubic LLC dispersions, or cubosomes, using photoswitchable amphiphiles to enable external control over the LLC structure and subsequent on-demand release of entrapped guest molecules. Azobenzene photosurfactants (AzoPS), containing a neutral tetraethylene glycol head group and azobenzene-alkyl tail, are combined (from 10-30 wt %) into monoolein-water systems to create LLC phases. Homogenization of the bulk LLC forms dispersions of particles, ∼200 nm in diameter with internal bicontinuous primitive cubic phases, as seen using small-angle X-ray scattering and cryo-transmission electron microscopy. Notably, increasing the AzoPS concentration leads to swelling of the cubic lattice, offering a method to tune the internal nanoscale structure. Upon UV irradiation, AzoPS within the cubosomes isomerizes within seconds, which in turn leads to squeezing of the cubic lattice and a decrease in the lattice parameter. This squeeze mechanism was successfully harnessed to enable phototriggerable release of trapped Nile Red guest molecules from the cubosome structure in minutes. The ability to control the internal structure of LLC dispersions using light, and the dramatic effect this has on the retention of entrapped molecules, suggests that these systems may have huge potential for the next-generation of nanodelivery.

Porous Polymer Cubosomes with Ordered Single Primitive Bicontinuous Architecture and Their Sodium-Iodine Batteries

Bicontinuous porous materials, which possess 3D interconnected pore channels facilitating a smooth mass transport, have attracted much interest in the fields of energy and catalysis. However, their synthesis remains very challenging. We report a general approach, using polymer cubosomes as the template, for the controllable synthesis of bicontinuous porous polymers with an ordered single primitive (SP) cubic structure, including polypyrrole (SP-PPy), poly-m-phenylenediamine (SP-PmPD), and polydopamine (SP-PDA). Specifically, the resultant SP-PPy had a unit cell parameter of 99 nm, pore diameter of 45 nm, and specific surface area of approximately 60 m²·g^-1. As a proof of concept, the I₂-adsorbed SP-PPy was employed as the cathode materials of newly emerged Na-I₂ batteries, which delivered a record-high specific capacity (235 mA·h·g^-1 at 0.5 C), excellent rate capability, and cycling stability (with a low capacity decay of 0.12% per cycle within 400 cycles at 1 C). The advantageous contributions of the bicontinuous structure and I₃^- adsorption mechanism of SP-PPy were revealed by a combination of ion diffusion experiments and theoretical calculations. This study opens a new avenue for the synthesis of porous polymers with new topologies, broadens the spectrum of bicontinuous-structured materials, and also develops a novel potential application for porous polymers.

Cubosomal Lipid Formulation for Combination Cancer Treatment: Delivery of a Chemotherapeutic Agent and Complexed α-Particle Emitter 213Bi

Here, we propose tailored lipid liquid-crystalline carriers (cubosomes), which incorporate an anticancer drug (doxorubicin) and complexed short-lived α-emitter (bismuth-213), as a strategy to obtain more effective action toward the cancer cells. Cubosomes were formulated with doxorubicin (DOX) and an amphiphilic ligand (DOTAGA-OA), which forms stable complexes with ²¹³Bi radionuclide. The behavior of DOX incorporated into the carrier together with the chelating agent was investigated, and the drug liberation profile was determined. The experiments revealed that the presence of the DOTAGA-OA ligand affects the activity of DOX when they are incorporated into the same carrier. This unexpected influence was explained based on the results of release studies, which proved the contribution of electrostatics in molecular interactions between the positively charged DOX and negatively charged DOTAGA-OA in acidic and neutral solutions. A significant decrease in the viability of HeLa cancer cells was achieved using sequential cell exposure: first to the radiolabeled cubosomes containing ²¹³Bi complex and next to DOX-doped cubosomes. Therefore, the sequential procedure for the delivery of both drugs encapsulated in cubosomes is suggested for further biological and in vivo studies.

Biomineral-Inspired Colloidal Liquid Crystals: From Assembly of Hybrids Comprising Inorganic Nanocrystals and Organic Polymer Components to Their Functionalization

Bioinspired organic/inorganic synthetic composites have been studied as high-performance and functional materials. In nature, biominerals such as pearls, teeth, and bones are self-organized organic/inorganic composites. The inorganic components are composed of calcium carbonate (CaCO3) and hydroxyapatite (HAp), while the organic components consist of peptides and polysaccharides. These composites are used as structural materials in hard biological tissues. Biominerals do not show significantly higher performances than synthetic composites such as glass-fiber- or carbon-fiber-reinforced plastics. However, biominerals consist of environmentally friendly and biocompatible components that are prepared under mild conditions. Moreover, they form elaborate nanostructures and self-organized hierarchical structures. Much can be learned about material design from these biomineral-based hierarchical and nanostructured composites to assist in the preparation of functional materials.Inspired by these biological hard tissues, we developed nanostructured thin films and bulk hybrid crystals through the self-organization of organic polymers and inorganic crystals of CaCO3 or HAp. In biomineralization, the combination of insoluble components and soluble acidic macromolecules controls the crystallization process. We have shown that poly(acrylic acid) (PAA) or acidic peptides called polymer additives induce the formation of thin film crystals of CaCO3 or HAp by cooperation with insoluble organic templates such as chitin and synthetic polymers bearing the OH group. Moreover, we recently developed CaCO3- and HAp-based nanostructured particles with rod and disk shapes. These were obtained in aqueous media using a macromolecular acidic additive, PAA, without using insoluble polymer templates. At appropriate concentrations, the anisotropic particles self-assembled and formed colloidal liquid-crystalline (LC) phases.LC materials are generally composed of organic molecules. They show ordered and mobile states. The addition of stimuli-responsive properties to organic rod-like LC molecules led to the successful development of informational displays, which are now widely used. On the other hand, colloidal liquid crystals are colloidal self-assembled dispersions of anisotropic organic and inorganic nano- and micro-objects. For example, polysaccharide whiskers, clay nanosheets, gibbsite plate-shaped particles, and silica rod-shaped particles exhibit colloidal LC states.In this Account, we focused on the material design and hierarchical aspects of biomineral-based colloidal LC polymer/inorganic composites. We describe the design and preparation, nanostructures, and self-assembled behavior of these new bioinspired and biocompatible self-organized materials. The characterization results for these self-assembled nanostructured colloidal liquid crystals found using high-resolution transmission electron microscopy, small-angle X-ray scattering, and neutron scattering and rheological measurements are also reported. The functions of these biomineral-inspired liquid crystals are presented. Because these biomineral-based LC colloidal liquid crystals can be prepared under mild and aqueous conditions and they consist of environmentally friendly and biocompatible components, new functions are expected for these materials.