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1.
J Hazard Mater ; 477: 135372, 2024 Sep 15.
Article in English | MEDLINE | ID: mdl-39106723

ABSTRACT

Tree bark has been proven as an effective passive air sampler, particularly where access to active sampling methods is limited. In this study, 60 target liquid crystal monomers (LCMs; comprising 10 cyanobiphenyl and analogs (CBAs), 13 biphenyl and analogs (BAs), and 37 fluorinated biphenyl and analogs (FBAs)) were analyzed in 34 tree barks collected from the vicinity of a liquid crystal display (LCD) manufacturer situated in the Pearl River Delta, South China. The concentrations of LCMs in tree barks ranged from 1400 to 16000 ng/g lipid weight, with an average of 5900 ng/g lipid weight. Generally, bark levels of BAs exponentially decreased within 5 km of the LCD manufacturer. The profiles of LCMs in tree barks are similar to previously reported patterns in gaseous phase, suggesting bark's efficacy as a sampler for gaseous LCMs. The inclusion of different congeners in existing studies on the environmental occurrence of LCMs has hindered the horizontal comparisons. Therefore, this study established a list of priority LCMs based on environmental monitoring data and the publicly accessible production data. This list comprised 146 LCMs, including 63 REACH registered LCMs that haven't been analyzed in any study and 56 belonging to 4 types of mainstream LCMs.


Subject(s)
Air Pollutants , Environmental Monitoring , Liquid Crystals , Plant Bark , Plant Bark/chemistry , Liquid Crystals/chemistry , Environmental Monitoring/methods , Air Pollutants/analysis , China , Biphenyl Compounds
2.
J Hazard Mater ; 477: 135365, 2024 Sep 15.
Article in English | MEDLINE | ID: mdl-39088946

ABSTRACT

The rapid and accurate identification of live pathogens with high proliferative ability is in great demand to mitigate foodborne infection outbreaks. Herein, we have developed an ultrasensitive image-based aptasensing array to directly detect live Salmonella typhimurium (S.T) cells. This method relies on the long-range orientation of surfactant-decorated liquid crystals (LCs) and the superiority of aptamers (aptST). The self-assembling of hydrophobic surfactant tails leads to a perpendicular/vertical ordered film at the aqueous/LC interface and signal-off response. The addition of aptST perturbed LCs' ordering into a planar/tilted state at the aqueous phase due to electrostatic interactions between the surfactant with the aptST, and a signal-on response. Following the conformational switch of aptST in the presence of live S. typhimurium, a relative reversing signal-off response was observed upon the target concentration. This aptasensor could promptly confirm the presence of S. typhimurium without intricate DNA-extraction or pre-enrichment stats over a linear range of 1-1.1 × 106 CFU/mL and a detection limit of 1.2 CFU/mL within ∼30 min. These results were successfully validated using molecular and culture-based methods in spiked-milk samples, with a 92.61-104.61 % recovery value. Meanwhile, the flexibility of this portable sensing platform allows for its development and adoption for the precise detection of various pathogens in food and the environment.


Subject(s)
Aptamers, Nucleotide , Liquid Crystals , Salmonella typhimurium , Salmonella typhimurium/isolation & purification , Liquid Crystals/chemistry , Aptamers, Nucleotide/chemistry , Surface-Active Agents/chemistry , Biosensing Techniques/methods , Milk/microbiology , Milk/chemistry , Limit of Detection , Food Microbiology , Animals
3.
J Colloid Interface Sci ; 674: 982-992, 2024 Nov 15.
Article in English | MEDLINE | ID: mdl-38964002

ABSTRACT

HYPOTHESIS: We hypothesize that simultaneous incorporation of ion channel peptides (in this case, potassium channel as a model) and hydrophobic magnetite Fe3O4 nanoparticles (hFe3O4NPs) within lipidic hexagonal mesophases, and aligning them using an external magnetic field can significantly enhance ion transport through lipid membranes. EXPERIMENTS: In this study, we successfully characterized the incorporation of gramicidin membrane ion channels and hFe3O4NPs in the lipidic hexagonal structure using SAXS and cryo-TEM methods. Additionally, we thoroughly investigated the conductive characteristics of freestanding films of lipidic hexagonal mesophases, both with and without gramicidin potassium channels, utilizing a range of electrochemical techniques, including impedance spectroscopy, normal pulse voltammetry, and chronoamperometry. FINDINGS: Our research reveals a state-of-the-art breakthrough in enhancing ion transport in lyotropic liquid crystals as matrices for integral proteins and peptides. We demonstrate the remarkable efficacy of membranes composed of hexagonal lipid mesophases embedded with K+ transporting peptides. This enhancement is achieved through doping with hFe3O4NPs and exposure to a magnetic field. We investigate the intricate interplay between the conductive properties of the lipidic hexagonal structure, hFe3O4NPs, gramicidin incorporation, and the influence of Ca2+ on K+ channels. Furthermore, our study unveils a new direction in ion channel studies and biomimetic membrane investigations, presenting a versatile model for biomimetic membranes with unprecedented ion transport capabilities under an appropriately oriented magnetic field. These findings hold promise for advancing membrane technology and various biotechnological and biomedical applications of membrane proteins.


Subject(s)
Gramicidin , Ion Transport , Liquid Crystals , Magnetite Nanoparticles , Liquid Crystals/chemistry , Gramicidin/chemistry , Magnetite Nanoparticles/chemistry , Peptides/chemistry , Particle Size , Ion Channels/chemistry , Ion Channels/metabolism , Magnetic Iron Oxide Nanoparticles/chemistry
4.
Biomacromolecules ; 25(8): 4977-4990, 2024 Aug 12.
Article in English | MEDLINE | ID: mdl-38949966

ABSTRACT

Cholesteric mesophases based on cellulose ethers, such as ethyl cellulose and hydroxypropyl cellulose, have been studied widely for their remarkable ability to display macroscopic structural color. However, the typical time scales involved in the multiscale self-assembly of cholesteric liquid crystals, from individual nanoscale helical arrangements to discrete microscopic domains, and their dependence on the gel's viscoelastic properties remain underexplored. Here, we establish a quantitative relationship between the kinetics of structural color formation after shear deformation and cholesteric order development at the nano- and microscales. Utilizing rheology in tandem with static and time-resolved reflectivity measurements, we underscore the strong influence of polymer diffusivity and chain elasticity on self-assembly kinetics in cholesteric cellulose ether gels. We show that our phenomenological model can be employed to assess the structure-property relationships of multiple polysaccharide systems, elucidating key design guidelines for the development and processing of structurally colored cholesteric mesophases.


Subject(s)
Cellulose , Cellulose/chemistry , Cellulose/analogs & derivatives , Kinetics , Rheology , Color , Liquid Crystals/chemistry , Gels/chemistry , Elasticity , Viscosity
5.
Molecules ; 29(13)2024 Jul 03.
Article in English | MEDLINE | ID: mdl-38999123

ABSTRACT

The drug delivery potential of liquid crystals (LCs) for ascorbyl palmitate (AP) was assessed, with the emphasis on the AP stability and release profile linked to microstructural rearrangement taking place along the dilution line being investigated by a set of complementary techniques. With high AP degradation observed after 56 days, two stabilization approaches, i.e., the addition of vitamin C or increasing AP concentration, were proposed. As a rule, LC samples with the lowest water content resulted in better AP stability (up to 52% of nondegraded AP in LC1 after 28 days) and faster API release (~18% in 8 h) as compared to the most diluted sample (29% of nondegraded AP in LC8 after 28 days, and up to 12% of AP released in 8 h). In addition, LCs exhibited a skin barrier-strengthening effect with up to 1.2-fold lower transepidermal water loss (TEWL) and 1.9-fold higher skin hydration observed in vitro on the porcine skin model. Although the latter cannot be linked to LCs' composition or specific microstructure, the obtained insight into LCs' microstructure contributed greatly to our understanding of AP positioning inside the system and its release profile, also influencing the overall LCs' performance after dermal application.


Subject(s)
Ascorbic Acid , Liquid Crystals , Phospholipids , Skin , Ascorbic Acid/analogs & derivatives , Ascorbic Acid/chemistry , Liquid Crystals/chemistry , Animals , Swine , Skin/metabolism , Skin/drug effects , Phospholipids/chemistry , Drug Liberation , Drug Stability , Drug Delivery Systems
6.
Water Res ; 261: 122062, 2024 Sep 01.
Article in English | MEDLINE | ID: mdl-39002419

ABSTRACT

Liquid crystal monomers (LCMs) are a new class of emerging pollutants with high octanol-water partition coefficients; however, their transformation behavior and associated risk to environments with high organic matter content has rarely been reported. In this study, we investigated the photodegradation kinetics, mechanism, and toxicity variation of 23 LCMs on leaf wax models (e.g., organic solvents methanol and n-hexane). The order of the photolysis rates of these LCMs were biphenylethyne LCMs > phenylbenzoate LCMs > diphenyl/terphenyl LCMs under simulated sunlight, while the phenylcyclohexane LCMs were resistant to photodegradation. The phenylbenzoate and biphenylethyne LCMs mainly undergo direct photolysis, while the diphenyl/terphenyl LCMs mainly undergo self-sensitized photolysis. The main photolysis pathways are the cleavage of ester bonds for phenylbenzoate LCMs, the addition, oxidation and cleavage of alkynyl groups for biphenylethyne LCMs, and the cleavage/oxidation of chains attached to phenyls and the benzene ring opening for diphenyl/terphenyls LCMs. Most photolysis products remained toxic to aquatic organisms to some degree. Additionally, two quantitative structure-activity relationship models for predicting kobs of LCMs in methanol and n-hexane were developed, and employed to predict kobs of 93 LCMs to fill the kobs data gap in systems mimicking leaf surfaces. These results can be helpful for evaluating the fate and risk of LCMs in environments with high content of organic phase.


Subject(s)
Liquid Crystals , Photolysis , Quantitative Structure-Activity Relationship , Kinetics , Liquid Crystals/chemistry , Sunlight
7.
Anal Chem ; 96(28): 11472-11478, 2024 07 16.
Article in English | MEDLINE | ID: mdl-38957093

ABSTRACT

It is well-known that the bacterial microenvironment imposes restrictions on the growth and behavior of bacteria. The localized monitoring of microenvironmental factors is appreciated when consulting bacterial adaptation and behavior in the presence of chemical or mechanical stimuli. Herein, we developed a novel liquid crystal (LC) biosensor in a microsphere configuration for real-time 3D monitoring of the bacteria microenvironment, which was implemented by a microfluidic chip. As a proof of concept, a LC gel (LC-Gel) microsphere biosensor was prepared and employed in the localized pH changes of bacteria by observing the configuration change of LC under polarized optical microscopy. Briefly, the microsphere biosensor was constructed in core-shell configuration, wherein the core contained LCE7 (a nematic LC) doped with 4-pentylbiphenyl-4'-carboxylic acid (PBA), and the shell encapsulated the bacteria. The protonation of carboxyl functional groups of the PBA induced a change in charge density on the surface of LCE7 and the orientation of E7 molecules, resulting in the transitions of the LC nucleus from axial to bipolar. The developed LC-Gel microspheres pH sensor exhibited its dominant performance on localized pH real-time sensing with a resolution of 0.1. An intriguing observation from the prepared pH biosensor was that the diverse bacteria impelled distinct acidifying or alkalizing effects. Overall, the facile LC-Gel microsphere biosensor not only provides a versatile tool for label-free, localized pH monitoring but also opens avenues for investigating the effects of chemical and mechanical stimuli on cellular metabolism within bacterial microenvironments.


Subject(s)
Biosensing Techniques , Liquid Crystals , Microspheres , Hydrogen-Ion Concentration , Liquid Crystals/chemistry , Escherichia coli
8.
Soft Matter ; 20(30): 6068-6079, 2024 Jul 31.
Article in English | MEDLINE | ID: mdl-39037726

ABSTRACT

We develop a microscopic model of antibiotic diffusion in virus suspensions in a liquid crystalline state. We then approximate this with an effective homogenised model that is more amenable to analytical investigation, to understand the effect of charge on the antibiotic tolerance. We show that liquid crystalline virus suspensions slow down antibiotics significantly, and that electric charge strongly contributes to this by influencing the effective diameter and adsorptive capacity of the liquid crystalline viruses so that charged antibiotics diffuse much slower than neutral ones; this can be directly and efficiently derived from the homogenised model and is in good agreement with experiments in microbiology. Charge is also found to affect the relationship between antibiotic diffusion and viral packing density in a nontrivial way. The results elucidate the effect of charge on antibiotic tolerance in liquid crystalline biofilms in a manner that is straightforwardly extendable to other soft matter systems.


Subject(s)
Anti-Bacterial Agents , Liquid Crystals , Adsorption , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Diffusion , Liquid Crystals/chemistry , Suspensions/chemistry , Biofilms/drug effects , Viruses/drug effects , Viruses/chemistry
9.
Biomacromolecules ; 25(7): 3920-3929, 2024 Jul 08.
Article in English | MEDLINE | ID: mdl-38826125

ABSTRACT

DNA oligomers in solution have been found to develop liquid crystal phases via a hierarchical process that involves Watson-Crick base pairing, supramolecular assembly into columns of duplexes, and long-range ordering. The multiscale nature of this phenomenon makes it difficult to quantitatively describe and assess the importance of the various contributions, particularly for very short strands. We performed molecular dynamics simulations based on the coarse-grained oxDNA model, aiming to depict all of the assembly processes involved and the phase behavior of solutions of the DNA GCCG tetramers. We find good quantitative matching to experimental data at both levels of molecular association (thermal melting) and collective ordering (phase diagram). We characterize the isotropic state and the low-density nematic and high-density columnar liquid crystal phases in terms of molecular order, size of aggregates, and structure, together with their effects on diffusivity processes. We observe a cooperative aggregation mechanism in which the formation of dimers is less thermodynamically favored than the formation of longer aggregates.


Subject(s)
DNA , Liquid Crystals , Molecular Dynamics Simulation , DNA/chemistry , Liquid Crystals/chemistry , Phase Transition , Thermodynamics , Nucleic Acid Conformation , Base Pairing
10.
Analyst ; 149(14): 3828-3838, 2024 Jul 08.
Article in English | MEDLINE | ID: mdl-38855814

ABSTRACT

Norfloxacin (NOX), a broad spectrum fluoroquinolone (FQ) antibiotic, is commonly detected in environmental residues, potentially contributing to biological drug resistance. In this paper, an aptamer recognition probe has been used to develop a label-free liquid crystal-based biosensor for simple and robust optical detection of NOX in aqueous solutions. Stimuli-receptive liquid crystals (LCs) have been employed to report aptamer-target binding events at the LC-aqueous interface. The homeotropic alignment of LCs at the aqueous-LC interface is due to the self-assembly of the cationic surfactant cetyltrimethylammonium bromide (CTAB). In the presence of the negatively charged NOX aptamer, the ordering changes to planar/tilted. On addition of NOX, the aptamer-NOX binding causes redistribution of CTAB at the LC-aqueous interface and the homeotropic orientation is restored. This results in a bright-to-dark optical transition under a polarized optical microscope (POM). This optical transition serves as a visual indicator to mark the presence of NOX. The devised aptasensor demonstrates high specificity with a minimum detection limit of 5 nM (1.596 ppb). Moreover, the application of the developed aptasensor for the detection of NOX in freshwater and soil samples underscores its practical utility in environmental monitoring. This proposed LC-based method offers several advantages over conventional detection techniques for a rapid, feasible and convenient way to detect norfloxacin.


Subject(s)
Aptamers, Nucleotide , Biosensing Techniques , Lakes , Limit of Detection , Liquid Crystals , Norfloxacin , Norfloxacin/analysis , Norfloxacin/chemistry , Aptamers, Nucleotide/chemistry , Liquid Crystals/chemistry , Lakes/analysis , Lakes/chemistry , Biosensing Techniques/methods , Soil/chemistry , Anti-Bacterial Agents/analysis , Anti-Bacterial Agents/chemistry , Water Pollutants, Chemical/analysis , Water Pollutants, Chemical/chemistry , Cetrimonium/chemistry
11.
Int J Mol Sci ; 25(12)2024 Jun 12.
Article in English | MEDLINE | ID: mdl-38928182

ABSTRACT

Enantioseparation of nineteen liquid crystalline racemic mixtures obtained based on (R,S)-2-octanol was studied in reversed-phase mode on an amylose tris(3-chloro-5-methylphenylcarbamate) (ReproSil Chiral-MIG) and a cellulose tris(3,5-dichlorophenylcarbamate) (ReproSil Chiral-MIC). These polysaccharide-based chiral stationary phase (CSP) columns for High-Performance Liquid Chromatography (HPLC) were highly effective in recognizing isomers of minor structural differences. The mobile phase (MP), which consists of acetonitrile (ACN)/water (H2O) at different volume ratios, was used. The mobile phases were pumped at a flow rate of 0.3, 0.5, or 1 mL·min-1 with a column temperature of 25 °C, using a UV detector at 254 nm. The order of the elution was also determined. The chromatographic parameters, such as resolution (Rs), selectivity (α), and the number of theoretical plates, i.e., column efficiency (N), were determined. The polysaccharide-based CSP columns have unique advantages in separation technology, and this study has shown the potential usefulness of the CSP columns in separating liquid crystalline racemic mixtures belonging to the same homologous series.


Subject(s)
Chromatography, Reverse-Phase , Liquid Crystals , Polysaccharides , Liquid Crystals/chemistry , Stereoisomerism , Chromatography, Reverse-Phase/methods , Chromatography, High Pressure Liquid/methods , Polysaccharides/chemistry , Amylose/chemistry , Amylose/analogs & derivatives , Cellulose/chemistry , Cellulose/analogs & derivatives , Phenylcarbamates/chemistry
12.
ACS Appl Mater Interfaces ; 16(24): 31843-31850, 2024 Jun 19.
Article in English | MEDLINE | ID: mdl-38841859

ABSTRACT

Liquid crystal (LC) biosensors have received significant attention for their potential applications for point-of-care devices due to their sensitivity, low cost, and easy read-out. They have been employed to detect a wide range of important biological molecules. However, detecting the function of membrane proteins has been extremely challenging due to the difficulty of integrating membrane proteins, lipid membranes, and LCs into one system. In this study, we addressed this challenge by monitoring the proton-pumping function of bacteriorhodopsin (bR) using a pH-sensitive LC thin film biosensor. To achieve this, we deposited purple membranes (PMs) containing a 2D crystal form of bRs onto an LC-aqueous interface. Under light, the PM patches changed the local pH at the LC-aqueous interface, causing a color change in the LC thin film that is observable through a polarizing microscope with crossed polarizers. These findings open up new opportunities to study the biofunctions of membrane proteins and their induced local environmental changes in a solution using LC biosensors.


Subject(s)
Bacteriorhodopsins , Biosensing Techniques , Liquid Crystals , Biosensing Techniques/methods , Liquid Crystals/chemistry , Hydrogen-Ion Concentration , Bacteriorhodopsins/chemistry , Membrane Proteins/chemistry , Purple Membrane/chemistry
13.
J Mater Chem B ; 12(28): 6757-6773, 2024 Jul 17.
Article in English | MEDLINE | ID: mdl-38916076

ABSTRACT

Deformable liquid crystal polymers (LCPs), which exhibit both entropic elasticity of polymer networks and anisotropic properties originating from ordered mesogens, have gained more and more interest for use as biomedical soft actuators. Especially, LCP actuators with controllable mesogen alignment, sophisticated geometry and reprogrammability are a rising star on the horizon of soft actuators, since they enable complex and multiple actuations. This review focuses on two topics: (1) the regulation of mesogen alignment and geometry of LCP actuators for complex actuations; (2) newly designed reprogrammable LCP materials for multiple actuations. First, basic actuation mechanisms are briefly introduced. Then, LCP actuators with complex actuations are demonstrated. Special attention is devoted to the improvement of fabrication methods, which profoundly influence the available complexity of the mesogen alignment and geometry. Subsequently, reprogrammable LCP actuators featuring dynamic networks or shape memory effects are discussed, with an emphasis on their multiple actuations. Finally, perspectives on the current challenges and potential development trends toward more intelligent LCP actuators are discussed, which may shed light on future investigations in this field.


Subject(s)
Polymers , Polymers/chemistry , Liquid Crystals/chemistry
14.
Macromol Rapid Commun ; 45(16): e2400193, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38837543

ABSTRACT

Photo-responsive liquid crystal polymers (LCPs) have potential application value in flexible robots, artificial muscles, and microfluidic control. In recent years, significant progress has been made in the development of LCPs. However, the preparation of LCPs with continuous and controllable stepwise deformation capabilities remains a challenge. In this study, visible photo-responsive cyanostilbene monomer, UV photo-responsive azobenzene monomer, and multiple hydrogen bond crosslinker are used to prepare photo-responsive LCPs capable of achieving continuously and controllable stepwise deformation. The comprehensive investigation of the multiple light response ability and photo-induced deformation properties of these copolymers is conducted. The results reveal that in the first stage of photo-induced deformation under 470 nm blue light irradiation, the deformation angle decreases with a reduction in cyanostilbene content in the copolymer component, ranging from 40° in AZ0-CS4 to 0° in AZ4-CS0. In the second stage of photo-induced deformation under 365 nm UV irradiation, the deformation angle increases with the increase of azobenzene content, ranging from 0° of AZ0-CS4 to 89.4° of AZ4-CS0. Importantly, the deformation between these two stages occurs as a continuous process, allowing for a direct transition from the first-stage to the second-stage deformation by switching the light source from 470 to 365 nm.


Subject(s)
Polymers , Polymers/chemistry , Polymers/chemical synthesis , Ultraviolet Rays , Photochemical Processes , Azo Compounds/chemistry , Liquid Crystals/chemistry , Molecular Structure , Light , Hydrogen Bonding
15.
Environ Pollut ; 356: 124285, 2024 Sep 01.
Article in English | MEDLINE | ID: mdl-38823544

ABSTRACT

Liquid crystal monomers (LCMs), which are commonly used in electronic device screens, have attracted attention as a potential class of emerging organic pollutants with persistent, bioaccumulative, and toxic (PBT) properties. This study involved the collection of 54 surface soil samples around one LC industrial park at increasing spatial distances within 1 km, 1-3 km, and 3-5 km from the center of the LC industrial park. Our observations revealed the presence of LCMs in 46 of 54 surface soil samples examined. Of the 39 target LCMs, 36 were identified, comprising 14 non-fluorinated and 22 fluorinated LCMs. Nine LCMs were detected at frequencies exceeding 20%, with 3bcHdFB exhibiting the highest detection frequency of 59% in the soil samples. The total LCM concentrations across the 46 sampling locations varied from 0.0072 to 17.24 ng/g dw, with the highest total concentrations at sampling sites within 1 km of the liquid crystal plant, suggesting that manufacturing processes may be a potential source for LCM release into the environment. Differences were observed in the LCM contamination patterns among the three sampling areas. Additionally, we observed a decrease in the median LCM concentration with increasing distance from the center of the LC industrial park. However, no statistically significant differences (p > 0.05) in LCM concentrations were observed across the three distances assessed in this study. This may be owing to the limited variety of target compounds analyzed and the limited number of soil samples. Our results emphasize that further studies on the emissions and pollution characteristics of LCMs during production are warranted.


Subject(s)
Environmental Monitoring , Liquid Crystals , Soil Pollutants , Soil , Soil Pollutants/analysis , Liquid Crystals/chemistry , Environmental Monitoring/methods , Soil/chemistry
16.
J Phys Chem B ; 128(20): 5127-5134, 2024 May 23.
Article in English | MEDLINE | ID: mdl-38736379

ABSTRACT

Lyotropic liquid crystals (LLCs) have attracted considerably growing interest in drug delivery applications over the last years. The structure of LLC matrices is complementary to cell membranes and provides an efficient, controlled, and selective release of drugs. In this work, a complex of experimental methods was used to characterize binary LLCs Pluronic P123/DMSO and triple LLC systems Pluronic P123/DMSO/Ibuprofen, which are interesting as transdermal drug delivery systems. Liquid crystalline, thermal, and rheological properties of LLCs were studied. Concentration and temperature areas of the lyomesophase existence were found, and phase transition enthalpies were evaluated. Intermolecular interactions among the components were studied by infrared (IR) spectroscopy. In vitro studies of Ibuprofen (Ibu) release from various LLCs allow differentiation of its release depending on the polymer content. Atomic force microscopy and contact angle methods were used to characterize the surface morphology of the hydrophobic membrane, which was used as a stratum corneum model, and also evaluate the adhesion work of the LLCs. A complex analysis of the results provided by these experimental methods allowed revealing correlations between the phase behavior and rheological characteristics of the LLCs and release kinetics of ibuprofen. The proposed biocompatible systems have considerable potential for a transdermal delivery of bioactive substances.


Subject(s)
Ibuprofen , Liquid Crystals , Poloxalene , Liquid Crystals/chemistry , Ibuprofen/chemistry , Ibuprofen/administration & dosage , Poloxalene/chemistry , Rheology , Administration, Topical , Drug Liberation
17.
ACS Appl Mater Interfaces ; 16(19): 25404-25414, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38692284

ABSTRACT

Liquid crystal elastomers (LCEs), as a classical two-way shape-memory material, are good candidates for developing artificial muscles that mimic the contraction, expansion, or rotational behavior of natural muscles. However, biomimicry is currently focused more on the actuation functions of natural muscles dominated by muscle fibers, whereas the tactile sensing functions that are dominated by neuronal receptors and synapses have not been well captured. Very few studies have reported the sensing concept for LCEs, but the signals were still donated by macroscopic actuation, that is, variations in angle or length. Herein, we develop a conductive porous LCE (CPLCE) using a solvent (dimethyl sulfoxide (DMSO))-templated photo-cross-linking strategy, followed by carbon nanotube (CNT) incorporation. The CPLCE has excellent reversible contraction/elongation behavior in a manner similar to the actuation functions of skeletal muscles. Moreover, the CPLCE shows excellent pressure-sensing performance by providing real-time electrical signals and is capable of microtouch sensing, which is very similar to natural tactile sensing. Furthermore, macroscopic actuation and tactile sensation can be integrated into a single system. Proof-of-concept studies reveal that the CPLCE-based artificial muscle is sensitive to external touch while maintaining its excellent actuation performance. The CPLCE with tactile sensation beyond reversible actuation is expected to benefit the development of versatile artificial muscles and intelligent robots.


Subject(s)
Elastomers , Liquid Crystals , Nanotubes, Carbon , Liquid Crystals/chemistry , Elastomers/chemistry , Nanotubes, Carbon/chemistry , Porosity , Solvents/chemistry , Touch/physiology , Artificial Organs , Muscle, Skeletal/physiology , Muscle, Skeletal/chemistry , Humans
18.
ACS Appl Mater Interfaces ; 16(22): 29098-29111, 2024 Jun 05.
Article in English | MEDLINE | ID: mdl-38780083

ABSTRACT

In this work, an injectable in situ depot-forming lipidic lyotropic liquid crystal (L3C) system is developed to codeliver a precisely synchronized combination of chemotherapeutics intratumorally. The developed L3C system is composed of amphiphilic lipids and surfactants, including monoolein, phosphatidylcholine, tocopherol acetate, and d-α-tocopherol polyethylene glycol 1000 succinate. Owing to its amphiphilic nature, the developed formulation can coaccommodate both hydrophobic and hydrophilic chemotherapeutic moieties simultaneously. The study presents a proof of concept by designing a combination chemotherapy regimen in vitro and demonstrating its in vivo translation using doxorubicin and paclitaxel as model hydrophilic and hydrophobic drug moieties, respectively. The synchronized combination of the two chemotherapeutics with maximum synergistic activity was identified, coloaded in the developed L3C system at predefined stoichiometric ratios, and evaluated for antitumor efficacy in the 4T1 breast tumor model in BALB/c mice. The drug-loaded L3C formulation is a low-viscosity injectable fluid with a lamellar phase that transforms into a hexagonal mesophase depot system upon intratumoral injection. The drug-loaded depot system locally provides sustained intratumoral delivery of the chemotherapeutics combination at their precisely synchronized ratio for over a period of one month. Results demonstrate that the exposure of the tumor to the precisely synchronized intratumoral chemotherapeutics combination via the developed L3C system resulted in significantly higher antitumor activity and reduced cardiotoxicity compared to the unsynchronized combination chemotherapy or the synchronized but uncoordinated drug delivery administered by a conventional intravenous route. These findings demonstrate the potential of the developed L3C system for achieving synchronized codelivery of the chemotherapeutics combination intratumorally and improving the efficacy of combination chemotherapy.


Subject(s)
Doxorubicin , Liquid Crystals , Mice, Inbred BALB C , Animals , Liquid Crystals/chemistry , Mice , Doxorubicin/chemistry , Doxorubicin/pharmacology , Female , Paclitaxel/chemistry , Paclitaxel/pharmacology , Paclitaxel/pharmacokinetics , Cell Line, Tumor , Humans , Glycerides/chemistry , Antineoplastic Combined Chemotherapy Protocols/pharmacology , Antineoplastic Combined Chemotherapy Protocols/chemistry , Antineoplastic Combined Chemotherapy Protocols/pharmacokinetics , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Drug Carriers/chemistry
19.
Eur J Pharm Biopharm ; 200: 114343, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38801980

ABSTRACT

Responsive and adaptive soft-matter systems represent an advanced category of materials with potential applications in drug delivery. Among these, liquid crystals (LCs) emerge as multifunctional anisotropic scaffolds capable of reacting to temperature, light, electric or magnetic fields. Specifically, the ordering and physical characteristics of thermotropic LCs are primarily contingent on temperature as an external stimulus. This comprehensive review aims to bridge a notable gap in the biomedical application of thermotropic mesogens by exclusively focusing on drug delivery. Anticipated to inspire diverse ideas, the review intends to facilitate the elegant exploitation of controllable and temperature-induced characteristics of LCs to enhance drug permeation. Here, we delineate recent advancements in thermally-driven LCs with a substantial emphasis on LC monomer mixtures, elastomers, polymers, microcapsules and membranes. Moreover, special emphasis is placed on the biocompatibility and toxicity of LCs as the foremost prerequisite for their application in healthcare. Given the promising prospect of thermotropic LC formulations in a clinical context, a special section is devoted to skin drug delivery. The review covers content from multiple disciplines, primarily targeting researchers interested in innovative strategies in drug delivery. It also appeals to those enthusiastic about firsthand exploration of the feasible biomedical applications of thermotropic LCs. To the best of our knowledge, this marks the first review addressing thermotropic LCs as tunable soft-matter systems for drug delivery.


Subject(s)
Delayed-Action Preparations , Drug Carriers , Drug Delivery Systems , Liquid Crystals , Temperature , Liquid Crystals/chemistry , Humans , Drug Delivery Systems/methods , Drug Carriers/chemistry , Animals , Drug Liberation , Polymers/chemistry , Skin/metabolism , Skin/drug effects , Administration, Cutaneous
20.
J Control Release ; 371: 298-312, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38815703

ABSTRACT

Wound management is a critical clinical challenge due to the dynamic and complex pathological characteristics of inflammation, proliferation, and matrix remodeling. To address this challenge, the regulation and management of this multi-stage pathological microenvironment may provide a feasible approach to wound healing. In this work, we synthesized a new lipid material (DA) with reactive oxygen species (ROS) scavenging effect to prepare DA-based liquid crystalline (DALC). Then, DALC was incorporated with adipose mesenchymal stem cells-derived extracellular vesicles (AMSC-EVs) to fabricate a novel scaffold dressing (EVs@DALC) for the treatment of the wound. DALC not only endowed EVs@DALC with ROS scavenging sites for relieving the oxidative stress and inflammation in the microenvironment of the wound site, but also facilitated cellular uptake and transfection of microRNA and growth factors contained in AMSC-EVs. Benefiting from DALC, AMSC-EVs effectively transferred microRNA and growth factors into the skin cells to induce cell proliferation and migration and accelerate angiogenesis. The results of wound healing effect in vivo indicate EVs@DALC achieved multi-stage pathological modulation for accelerating wound healing through alleviating inflammation, promoting cell proliferation and migration, and angiogenesis. Taken together, this work provides an effective strategy based on antioxidant lipid liquid crystalline delivering extracellular vesicles in treating skin wounds and paves a way for stem cell extracellular vesicles clinical translation.


Subject(s)
Cell Proliferation , Extracellular Vesicles , Lipids , Liquid Crystals , Mesenchymal Stem Cells , Reactive Oxygen Species , Wound Healing , Wound Healing/drug effects , Liquid Crystals/chemistry , Animals , Reactive Oxygen Species/metabolism , Humans , Lipids/chemistry , Cell Proliferation/drug effects , Male , Cell Movement/drug effects , MicroRNAs/administration & dosage , Skin/metabolism , Free Radical Scavengers/administration & dosage , Adipose Tissue/cytology , Mice
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