Self-assembly of perovskite nanocrystals:From driving forces to applications

Self-assembly of metal halide perovskite nanocrystals(NCs)into superlattices can exhibit unique collective properties,which have significant application values in the display,detector,and solar cell field.This review discusses the driving forces behind the self-assembly process of perovskite NCs,and the commonly used self-assembly methods and different self-assembly structures are detailed.Subsequently,we summarize the collective optoelectronic properties and application areas of perovskite superlattice structures.Finally,we conclude with an outlook on the potential issues and future challenges in developing perovskite NCs.

Alcohol solvent effect on the self-assembly behaviors of lignin oligomers

The interactions between lignin oligomers and solvents determine the behaviors of lignin oligomers self-assembling into uniform lignin nanoparticles(LNPs).Herein,several alcohol solvents,which readily interact with the lignin oligomers,were adopted to study their effects during solvent shifting process for LNPs’production.The lignin oligomers with widely distributed molecular weight and abundant guaiacyl units were extracted from wood waste(mainly consists of pine wood),exerting outstanding self-assembly capability.Uniform and spherical LNPs were generated in H_(2)O-n-propanol cosolvent,whereas irregular LNPs were obtained in H_(2)O-methanol cosolvent.The unsatisfactory self-assembly performance of the lignin oligomers in H_(2)O-methanol cosolvent could be attributed to two aspects.On one hand,for the initial dissolution state,the distinguishing Hansen solubility parameter and polarity between methanol solvent and lignin oligomers resulted in the poor dispersion of the lignin oligomers.On the other hand,strong hydrogen bonds between methanol solvent and lignin oligomers during solvent shifting process,hindered the interactions among the lignin oligomers for self-assembly.

Chitosan/Sodium Alginate Multilayer pH-Sensitive Films Based on Layer-by-Layer Self-Assembly for Intelligent Packaging

The abuse of plastic food packaging has brought about severe white pollution issues around the world.Developing green and sustainable biomass packaging is an effective way to solve this problem.Hence,a chitosan/sodium alginate-based multilayer film is fabricated via a layer-by-layer(LBL)self-assembly method.With the help of superior interaction between the layers,the multilayer film possesses excellent mechanical properties(with a tensile strength of 50 MPa).Besides,the film displays outstanding water retention property(blocking moisture of 97.56%)and ultraviolet blocking property.Anthocyanin is introduced into the film to detect the food quality since it is one natural plant polyphenol that is sensitive to the pH changes ranging from 1 to 13 in food when spoilage occurs.It is noted that the film is also bacteriostatic which is desired for food packaging.This study describes a simple technique for the development of advanced multifunctional and fully biodegradable food packaging film and it is a sustainable alternative to plastic packaging.

Hollow tubes constructed by carbon nanotubes self-assembly for CO_(2) capture

Carbon nanotubes(CNTs)have garnered significant attention in the fields of science,engineering,and medicine due to their numerous advantages.The initial step towards harnessing the potential of CNTs involves their macroscopic assembly.The present study employed a gentle and direct self-assembly technique,wherein controlled growth of CNT sheaths occurred on the metal wire’s surface,followed by etching of the remaining metal to obtain the hollow tubes composed of CNTs.By controlling the growth time and temperature,it is possible to alter the thickness of the CNTs sheath.After immersing in a solution containing 1 g/L of CNTs at 60℃ for 24 h,the resulting CNTs layer achieved a thickness of up to 60μm.These hollow CNTs tubes with varying inner diameters were prepared through surface reinforcement using polymers and sacrificing metal wires,thereby exhibiting exceptional attributes such as robustness,flexibility,air tightness,and high adsorption capacity that effectively capture CO_(2) from the gas mixture.

Mass transfer process of peanut protein extracted by bis(2-ethylhexyl)sodium sulfosuccinate reverse micelles

The liquid-liquid extraction method using reverse micelles can simultaneously extract lipid and protein of oilseeds,which have become increasingly popular in recent years.However,there are few studies on mass transfer processes and models,which are helpful to better control the extraction process of oils and proteins.In this paper,mass transfer process of peanut protein extracted by bis(2-ethylhexyl)sodium sulfosuccinate(AOT)/isooctane reverse micelles was investigated.The effects of stirring speed(0,70,140,and 210 r/min),temperature of extraction(30,35,40,45,and 50℃),peanut flour particle size(0.355,0.450,0.600,and 0.900 mm)and solidliquid ratio(0.010,0.0125,0.015,0.0175,and 0.020 g/mL)on extraction rate were examined.The results showed that extraction rate increased with temperature rising,particle size reduction as well as solid-liquid ratio increase respectively,while little effect of stirring speed(P>0.05)was observed.The apparent activation energy of extraction process was calculated as 10.02 kJ/mol and Arrhenius constant(A)was 1.91 by Arrhenius equation.There was a linear relationship between reaction rate constant and the square of the inverse of initial particle radius(1/r_(0)^(2))(P<0.05).This phenomenon and this shrinking core model were anastomosed.In brief,the extraction process was controlled by the diffusion of protein from the virgin zone interface of particle through the reacted zone and it was in line with the first order reaction.Mass transfer kinetics of peanut protein extracted by reverse micelles was established and it was verified by experimental results.The results provide an important theoretical guidance for industrial production of peanut protein separation and purification.

A Non-parametric Gradient-Based Shape Optimization Approach for Solving Inverse Problems in Directed Self-Assemblyof Block Copolymers

We consider the inverse problem of finding guiding pattern shapes that result in desired self-assembly morphologies of block copolymer melts.Specifically,we model polymer selfassembly using the self-consistent field theory and derive,in a non-parametric setting,the sensitivity of the dissimilarity between the desired and the actual morphologies to arbitrary perturbations in the guiding pattern shape.The sensitivity is then used for the optimization of the confining pattern shapes such that the dissimilarity between the desired and the actual morphologies is minimized.The efficiency and robustness of the proposed gradient-based algorithm are demonstrated in a number of examples related to templating vertical interconnect accesses(VIA).

Dual ligand-targeted Pluronic P123 polymeric micelles enhance the therapeutic effect of breast cancer with bone metastases

Bone metastasis secondary to breast cancer negatively impacts patient quality of life and survival.The treatment of bone metastases is challenging since many anticancer drugs are not effectively delivered to the bone to exert a therapeutic effect.To improve the treatment efficacy,we developed Pluronic P123(P123)-based polymeric micelles dually decorated with alendronate(ALN)and cancer-specific phage protein DMPGTVLP(DP-8)for targeted drug delivery to breast cancer bone metastases.Doxorubicin(DOX)was selected as the anticancer drug and was encapsulated into the hydrophobic core of the micelles with a high drug loading capacity(3.44%).The DOX-loaded polymeric micelles were spherical,123 nm in diameter on average,and exhibited a narrow size distribution.The in vitro experiments demonstrated that a pH decrease from 7.4 to 5.0 markedly accelerated DOX release.The micelles were well internalized by cultured breast cancer cells and the cell death rate of micelle-treated breast cancer cells was increased compared to that of free DOX-treated cells.Rapid binding of the micelles to hydroxyapatite(HA)microparticles indicated their high affinity for bone.P123-ALN/DP-8@DOX inhibited tumor growth and reduced bone resorption in a 3D cancer bone metastasis model.In vivo experiments using a breast cancer bone metastasis nude model demonstrated increased accumulation of the micelles in the tumor region and considerable antitumor activity with no organ-specific histological damage and minimal systemic toxicity.In conclusion,our study provided strong evidence that these pH-sensitive dual ligand-targeted polymeric micelles may be a successful treatment strategy for breast cancer bone metastasis.

Layer by Layer Self-assembly Fiber-based Flexible Electrochemical Transistor

Poly(3,4-ethylenedioxyethiophene)-polystyrene sulfonic acid(PEDOT:PSS)/polyallyl dimethyl ammonium chloride modified reduced graphene oxide(PDDA-rGO)was layer by layer self-assembled on the cotton fiber.The surface morphology and electric property was investigated.The results confirmed the dense membrane of PEDOT:PSS and the lamellar structure of PDDA-rGO on the fibers.It has excellent electrical conductivity and mechanical properties.The fiber based electrochemical transistor(FECTs)prepared by the composite conductive fiber has a maximum output current of 8.7 mA,a transconductance peak of 10 mS,an on time of 1.37 s,an off time of 1.6 s and excellent switching stability.Most importantly,the devices by layer by layer self-assembly technology opens a path for the true integration of organic electronics with traditional textile technologies and materials,laying the foundation for their later widespread application.

Interaction betweenamylose,fattyacid,andβ-lactoglobulinto study multiplebiomacromoleculesself-assemblyandapplication

New concept for the development of supramolecular assemblies from intricate inter-actions between different classes of biomacromolecules(polysaccharides,proteins and lipids)is yet to come,due to their intrinsic chemical and structural complex-ity and incompatibility.Herein,we report an interaction mechanism among multiple biomacromolecules,and the structural and digestive properties of their assemblies using amylose(AM),lauric acid(LA),andβ-lactoglobulin(βLG)as exemplars.AM,LA,andβLG interact to form a water-soluble ternary complex through van der Waals forces between AM and LA and high affinity binding between AM andβLG,which can further assemble into uniform-sized,semi-crystalline nanospheres under certain thermodynamic conditions.These nanospheres are substantially resis-tant to amylolysis,thus can be well utilized by gut microbiota,including increasing short-chain fatty acid levels and shaping bacterial communities.Illustrating the com-plexation of AM,LA,andβLG and their assemblies from disorder to order,this work offers potential rationale of assemblies for multiple biomacromolecules driven by non-covalent interactions and substantial potentials for supramolecular biomaterials development.

Optically active micelles from self-assembly of MPEG-b-PMALM copolymer in water

Reported here is fabrication of optically active micelles with broad range of morphologies in water, such as spheres, cylinders, and vesicles, from self-assembly of poly（ethylene glycol） monomethyl ether-b-poly- （methacryloyl-L-leucine methyl ester） （MPEG-b-PMALM） copolymer, which was prepared via atom transfer radical polymerization （ATRP） from vinyl monomer bearing chiral amino acid moieties, N-methacryloyl L-leucine methyl ester （MALM）, using bromine （Br） end-capped poly（ethylene golycol） monomethylether （MPEG-Br） as macroinitiator in the presence of CuBr/Me6TREN as catalytic system.

Intelligent self-assembly prodrug micelles loading doxorubicin in response to tumor microenvironment for targeted tumors therapy

Compared with physical drug-loaded nanocarriers,polymeric prodrug micelles have many advantages such as high drug loading and enhanced stability in blood,so they have great potential in cancer therapy.However,these micelles have a big disadvantage,which cannot achieve long-term circulation in vivo and high absorption of tumor cells simultaneously,resulting in low administration efficiency and poor therapeutic effect on cancer.To solve problems of traditional polymeric prodrug micelles,novel polymeric micelles with tumor microenvironment response were designed in this work.The prodrug formed by covalently linking D-α-tocopherol polyethylene glycol succinate(TPGS_(3350)),peptide(Pep),and doxorubicin(DOX)(TPGS_(3350)-Pep-DOX)was self-assembled into micelles by encapsulating DOX physically.When the micelles entered the tumor tissue,the long-chain polyethylene glycol(PEG)was sensitively cut by the matrix metalloproteinase 2/9(MMP2/9)enzyme,exposing the targeting molecule folate,then it entered the cell through the endocytic pathway mediated by the folate receptor.The drug loading content,encapsulation efficiency,critical micelle concentration,and invitro release of the micelles invented in this study were measured to characterize their properties.The particle size and zeta potential of micelles were characterized by dynamic light scattering.Images were scanned by transmission electron microscopes.In vitro cytotoxicity,cellular uptake,and in vivo antitumor effect evaluation experiments were measured to show that smart micelles have made much progress in material chemistry and drug delivery,making it possible to apply a stimulus-response carrier drug delivery system in clinical application.

Polyelectrolyte complex micelles by self-assembly of polypeptide-based triblock copolymer for doxorubicin delivery

Polyelectrolyte complex micelles were prepared by self-assembly of polypeptide-based triblock copolymer as a new drug carrier for cancer chemotherapy.The triblock copolymer,poly(L-aspartic acid)-b-poly(ethylene glycol)-b-poly(L-aspartic acid)(PLD-b-PEG-b-PLD),spontaneously self-assembled with doxorubicin(DOX)via electrostatic interactions to form spherical micelles with a particle size of 60e80 nm(triblock ionomer complexes micelles,TBIC micelles).These micelles exhibited a high loading capacity of 70%(w/w)at a drug/polymer ratio of 0.5 at pH 7.0.They showed pH-responsive release patterns,with higher release at acidic pH than at physiological pH.Furthermore,DOX-loaded TBIC micelles exerted less cytotoxicity than free DOX in the A-549 human lung cancer cell line.Confocal microscopy in A-549 cells indicated that DOX-loaded TBIC micelles were transported into lysosomes via endocytosis.These micelles possessed favorable pharmacokinetic characteristics and showed sustained DOX release in rats.Overall,these findings indicate that PLDb-PEG-b-PLD polypeptide micelles are a promising approach for anti-cancer drug delivery.

Mechanism for the Self-Assembly of Hollow Micelles from Rod-Coil Block Copolymers

The mechanism for the self-assembly of hollow micelles from rod-coil diblock copolymers is proposed. In a coilselective solvent, the diblock copolymers self-assemble into a layered structure. It is assumed that the rigid rods form an elastic shell whose properties are dictated by a bending energy. For a hollow micelle, the coils outside the micelle form a brush, while the coils inside the micelle can be in two different states, a brush or an adsorption layer, corresponding to symmetric or asymmetric configurations, respectively. The total energy density of a hollow micelle is calculated by combining the interfacial energy, elastic bending energy and the stretching energy of the brushes. For the asymmetric configuration with a polymer brush on one side, the competition between the elastic bending energy and the brush stretching energy leads to a finite spontaneous curvature, stabilizing hollow spherical micelles. Comparison of the free energy density for different geometries demonstrates that transitions for the different geometry micelles are controlled by the degree of polymerization of the coils and the length of the rods. These results are in agreement with the experimental results.

Pod-Like Supramicelles with Multicompartment Hydrophobic Cores Prepared by Self-Assembly of Modified Chitosan

In this paper, pod-like supramicelles with multicompartment hydrophobic cores were prepared by selfassembly of amphiphilic N-phthaloylchitosan-g-poly(N-vinylcaprolactam)(PHCS-g-PNVCL) in aqueous medium. The employed biocompatible amphiphilic polymer was synthesized by grafting the carboxyl terminated poly(N-vinylcaprolactam)(PNVCL-COOH) chains onto N-phthaloylchitosan(PHCS) backbone.~1H NMR and FTIR results confirmed the molecular structure of the copolymers. The morphology of the supramicelles assembled by PHCS-g-PNVCL was revealed by means of TEM and polarized light microscope. In solution, the supramicelles were very stable as monitored by DLS and zeta potential measurements. Temperature and p H presented significant influences on the size and size distribution of the supramicelles. These supramicelles with multicompartment hydrophobic cores should be ideal biomimetic systems with promising applications in drug delivery.

Combination therapy to overcome ferroptosis resistance by biomimetic self-assembly nano-prodrug

Ferroptosis has emerged as a potent form of no-apoptotic cell death that offers a promising alternative to avoid the chemoresistance of apoptotic pathways and serves as a vulnerability of cancer.Herein,we have constructed a biomimetic self-assembly nano-prodrug system that enables the co-delivery of gefitinib(Gefi),ferrocene(Fc)and dihydroartemisinin(DHA)for the combined therapy of both ferroptosis and apoptosis.In the tumor microenvironment,this nano-prodrug is able to disassemble and trigger drug release under high levels of GSH.Interestingly,the released DHA can downregulate GPX4 level for the enhancement of intracellular ferroptosis from Fc,further executing tumor cell death with concomitant chemotherapy by Gefi.More importantly,this nano-prodrug provides highly homologous targeting ability by coating related cell membranes and exhibits outstanding inhibition of tumor growth and metastasis,as well as no noticeable side-effects during treatments.This simple small molecular self-assembled nano-prodrug provides a new reasonably designed modality for ferroptosis-combined chemotherapy.

Construction of curcumin-loaded micelles and evaluation of the anti-tumor effect based on angiogenesis

Objective:Inhibition of tumor angiogenesis has become a new targeted tumor therapy.In this study,we established a micellar carrier with a tumor neovascularization-targeting effect modified by the neovascularization-targeting peptide NGR.Methods:The targeted polymer poly(ethylene glycol)-b-poly(lactide-co-glycolide)(PEG-PLGA)modified with Asn–Gly–Arg(NGR)peptide was prepared and characterized by 1H nuclear magnetic resonance and Fourier-transform infrared spectrometry.NGR-PEG-PLGA was used to construct curcumin(Cur)-loaded micelles by the solvent evaporation method.The physicochemical properties of the micelles were also investigated.Additionally,we evaluated the antitumor efficacy of the polymer micelles(PM)using in vitro cytology experiments and in vivo animal studies.Results:The particle size of Cur-NGR-PM was 139.70±2.51 nm,and the drug-loading capacity was 14.37±0.06%.In vitro cytological evaluation showed that NGR-modified micelles showed higher cellular uptake through receptor-mediated endocytosis pathways than did unmodified micelles,leading to the apoptosis of tumor cells.Then,in vivo antitumor experiments showed that the modified micelles significantly inhibited tumor growth and were safe.Conclusions:NGR-modified micelles significantly optimized the therapeutic efficacy of Cur.This strategy offers a viable avenue for cancer treatment.

Efficient conversion of lignin waste and self-assembly synthesis of C@MnCo_(2)O_(4)for asymmetric supercapacitors with high energy density

Lignin waste from the papermaking and biorefineries industry is a significantly promising renewable resource to prepare advanced carbon materials for diverse applications,such as the electrodes of supercapacitors;however,the improvement of their energy density remains a challenge.Here,we design a green and universal approach to prepare the composite electrode material,which is composed of lignin-phenolformaldehyde resins derived hierarchical porous carbon(LR-HPC)as conductive skeletons and the self-assembly manganese cobaltite(MnCo_(2)O_(4))nanocrystals as active sites.The synthesized C@MnCo_(2)O_(4)composite has an abundant porous structure and superior electronic conductivity,allowing for more charge/electron mass transfer channels and active sites for the redox reactions.The composite shows excellent electrochemical performance,such as the maximum specific capacitance of~726 mF cm^(-2)at 0.5 mV s^(-1),due to the significantly enhanced interactive interface between LR-HPC and MnCo_(2)O_(4)crystals.The assembled all-solid-state asymmetric supercapacitor,with the LR-HPC and C@MnCo_(2)O_(4)as cathode and anode,respectively,exhibits the highest volumetric energy density of 0.68 mWh cm^(-3)at a power density of 8.2 mW cm^(-3).Moreover,this device shows a high capacity retention ratio of~87.6%at 5 mA cm^(-2)after 5000 cycles.

Antibiotic-based small molecular micelles combined with photodynamic therapy for bacterial infections

The appearance of multidrug-resistant bacteria and the formation of bacterial biofilms have necessitated the development of alternative antimicrobial therapeutics.Antibiotics conjugated with or embedded in nano-drug carriers show a great potential and advantage over free drugs,but the mass proportion of carriers generally exceeds 90%of the nano-drug,resulting in low drug loading and limited therapeutic output.Herein,we fabricated a nanocarrier using antibiotics as the building blocks,minimizing the use of carriermaterials,significantly increasing the drug loading content and treatment effect.Firstly,we conjugated betaine carboxylate with ciprofloxacin(CIP)through an ester bond to form the amphiphilic conjugate(CIP-CB),which self-assembled into micelles(CIP-CBMs)in aqueous solutions,with a CIP loading content as high as 65.4%and pH-induced surface charge reversal properties.Secondly,a model photosensitizer(5,10,15,20-tetraphenylporphyrin(TPP))was encapsulated in CIP-CBMs,generating infection-targeted photodynamic/antibiotic combined nanomedicines(denoted as TPP@CIP-CBMs).Upon accumulation at infection sites or in deep bacterial biofilms,the ester bond between the betaine carboxylate and CIP is cleaved to release free TPP and CIP,leading to a synergetic antibacterial and antibiofilm activity in vitro and in vivo.

Preparation of adhesive resveratrol micelles and determination of drug content

Objective:Resveratrol polymer micelles with tissue adhesion were prepared and the content of resveratrol in the micelles was determined by HPLC.Method:The micelle adhesion experiment was carried out by polylysine orifice plate experiment and small animal fluorescence imaging method,and the micelle prescription was optimized to obtain resveratrol micelles with good adhesion.The separation was performed on a Shiseido SPOLAR C18 column(150 mm×4.6 mm,5μm)with methanol-water(42:58)as the mobile phase.The flow rate was 1.0 mL·min^(-1),the detection wavelength was 305 nm,the column temperature was 35℃,and the injection volume was 10μL.Results:Resveratrol micelles prepared with F127 alone had the best adhesion.The peak area and concentration of resveratrol had a good linear relationship in the concentration range of 10~200μg/mL(r=0.9996).The specificity,precision,recovery and stability all met the methodological requirements.Conclusion:In this experiment,resveratrol micelles with tissue adhesion were successfully prepared,and a method for the determination of resveratrol content in micelles was established.The method is accurate,rapid and simple.

Analysis on the formation principle and present situation of nano phase state of multi-component self-assembly of traditional Chinese compound medicine decoction

Traditional Chinese medicine decoction is a complex polydispersed phase system containing real solution,colloid solution,emulsion and suspension.The compound decoction of traditional Chinese medicine has complex components,including saponins,alkaloids,polysaccharides,flavonoids,amino acids and so on,which can be self-assembled to form gels,fibers,micelles,vesicles and so on.The self-assembled nano-phase not only neutralizes the single drug and reduces the toxicity and side effects,but also has its own pharmacological effects,which complement each other to achieve synergistic effect,so as to achieve the role of drug supplement,which is of research significance.The formation principle,solubilization and synergism principle and characterization method of multi-component self-assembly of traditional Chinese medicine compound decoction are discussed in this paper.