Multi-functional stimuli-responsive biomimetic flower assembled from CLCE and MOF-based pedals

Simulating the structures and behaviors of living organisms are of great significance to develop novel multi-functional intelligent devices. However, the development of biomimetic devices with complex deformable structures and synergistic properties is still on the way. Herein, we propose a simple and effective approach to create the multi-functional stimuli-responsive biomimetic devices with independently pre-programmable colorful visual patterns, complex geometries and morphable modes. The metal organic framework(MOF)-based composite film acts as a rigidity actuation substrate to support and mechanically guide the spatial configuration of the soft chiral nematic liquid crystal elastomer(CLCE) sheet. We can directly program the structural color of the CLCE sheet by adjusting the thickness distribution without tedious chemical modification. By using this coordination strategy, we fabricate an artificial flower, which exhibits a synergistic effect of both shape transformation and color change like paeonia ‘Coral Sunset’at different flowering stages, and can even perform different flowering behaviors by bending, twisting and curling petals. The assembled bionic flower is innovatively demonstrated to respond to local stimuli of humidity, heat or ultraviolet irradiation. Therefore, the spatial assembly of CLCE combined with functional MOF materials has a wide range of potential application in multi-functional integrated artificial systems.

Porous ultrathin-shell microcapsules designed by microfluidics for selective permeation and stimuli-triggered release

Microcapsules are versatile delivery vehicles and widely used in various areas.Generally,microcapsules with solid shells lack selective permeation and only exhibit a simple release mode.Here,we use ultrathin-shell water-in-oil-in-water double emulsions as templates and design porous ultrathin-shell microcapsules for selective permeation and multiple stimuli-triggered release.After preparation of double emulsions by microfluidic devices,negatively charged shellac nanoparticles dispersed in the inner water core electrostatically complex with positively charged telechelicα,ω-diamino functionalized polydimethylsiloxane polymers dissolved in the middle oil shell at the water/oil interface,thus forming a porous shell of shellac nanoparticles cross-linked by telechelic polymers.Subsequently,the double emulsions become porous microcapsules upon evaporation of the middle oil phase.The porous ultrathin-shell microcapsules exhibit excellent properties,including tunable size,selective permeation and stimuli-triggered release.Small molecules or particles can diffuse across the shell,while large molecules or particles are encapsulated in the core,and release of the encapsulated cargos can be triggered by osmotic shock or a pH change.Due to their unique performance,porous ultrathin-shell microcapsules present promising platforms for various applications,such as drug delivery.

Highly reliable and efficient encoding systems for hexadecimal polypeptide-based data storage

Polypeptides consisting of amino acid(AA)sequences are suitable for high-density information storage.However,the lack of suitable encoding systems,which accommodate the characteristics of polypeptide synthesis,storage and sequencing,impedes the application of polypeptides for large-scale digital data storage.To address this,two reliable and highly efficient encoding systems,i.e.RaptorQ-Arithmetic-Base64-Shuffle-RS(RABSR)and RaptorQArithmetic-Huffman-Rotary-Shuffle-RS(RAHRSR)systems,are developed for polypeptide data storage.The two encoding systems realized the advantages of compressing data,correcting errors of AA chain loss,correcting errors within AA chains,eliminating homopolymers,and pseudo-randomized encrypting.The coding efficiency without arithmetic compression and error correction of audios,pictures and texts by the RABSR system was 3.20,3.12 and 3.53 Bits/AA,respectively.While that using the RAHRSR system reached 4.89,4.80 and 6.84 Bits/AA,respectively.When implemented with redundancy for error correction and arithmetic compression to reduce redundancy,the coding efficiency of audios,pictures and texts by the RABSR system was 4.43,4.36 and 5.22 Bits/AA,respectively.This efficiency further increased to 7.24,7.11 and 9.82 Bits/AA by the RAHRSR system,respectively.Therefore,the developed hexadecimal polypeptide-based systems may provide a new scenario for highly reliable and highly efficient data storage.

Local high-density distributions of phospholipids induced by the nucleation and growth of smectic liquid crystals at the interface

Amphiphilic molecules adsorbed at the interface could control the orientation of liquid crystals(LCs)while LCs in turn could influence the distributions of amphiphilic molecules.The studies on the interactions between liquid crystals and amphiphilic molecules at the interface are important for the development of molecular sensors.In this paper,we demonstrate that the development of smectic LC ordering from isotropic at the LC/water interface could induce local high-density distributions of amphiphilic phospholipids.Mixtures of liquid crystals and phospholipids in chloroform are first emulsified in water.By fluorescently labeling the phospholipids adsorbed at the interface,their distributions are visualized under fluorescent confocal microscope.Interestingly,local high-density distributions of phospholipids showing a high fluorescent intensity are observed on the surface of LC droplets.Investigations on the correlation between phospholipid density,surface tension and smectic LC ordering suggest that when domains of smectic LC layers nucleate and grow from isotropic at the LC/water interface as chloroform slowly evaporates at room temperature,phospholipids transition from liquid-expanded to liquid-condensed phases in response to the smectic ordering,which induces a higher surface tension at the interface.The results will provide an important insight into the interactions between liquid crystals and amphiphilic molecules at the interface.

Pickering emulsions stabilized by colloidal surfactants:Role of solid particles

Pickering emulsions are emulsions stabilized by colloidal surfactants,i.e.solid particles.Compared with traditional molecular suffactant-stabilized emulsions,Pickering emulsions show many advantages,such as high resistance to coalescence,long-term stability,good biocompatibility and tunable properties.In recent years,Pickering emulsions are widely applied in scientific researches and industrial applications.In this review,we focus on the influences of particle properties on Pickering emulsions,including particle amphiphilicity,concentration,size and shape,and summarize the strategies developed for the preparation of amphiphilic Janus particles.The applications of Pickering emulsions in food industry,cosmetic industry,material science,drug delivery,biomedical research and vaccine adjuvant will also be covered.Pickering emulsions are a unique system for multi-disciplinary studies and will become more and more important in the future.

Dual-plasmid Editing System Improves DNA Digital Storage Potential

DNA-based information is a new interdisciplinary field linking information technology and biotechnology.The field hopes to meet the enormous need for long-term data storage by using DNA as an information storage medium.Despite DNA’s promise of strong stability,high storage density and low maintenance cost,researchers face problems in accurately rewriting digital information encoded in DNA sequences.

Oxygen microcapsules improve immune checkpoint blockade by ameliorating hypoxia condition in pancreatic ductal adenocarcinoma

Rationale:Hypoxia in tumor microenvironment(TME)represents an obstacle to the efficacy of immunotherapy for pancreatic ductal adenocarcinoma(PDAC)through several aspects such as increasing the expression of immune checkpoints or promoting fibrosis.Reversing hypoxic TME is a potential strategy to improve the validity of immune checkpoint blockade(ICB).Methods:Here,we synthesized polydopamine-nanoparticle-stabilized oxygen microcapsules with excellent stabilization,bioavailability,and biocompatibility for direct oxygen delivery into tumor sites by interfacial polymerization.Results:We observed oxygen microcapsules enhanced the oxygen concentration in the hypoxia environment and maintained the oxygen concentration for a long period both in vitro and in vivo.We found that oxygen microcapsules could significantly improve the efficiency of ICB against PDAC in vivo.Mechanismly,combined treatments using oxygen microcapsules and ICB could reduce the infiltration of tumor-associated macrophages(TAMs)and polarized pro-tumor M2 macrophages into anti-tumor M1 macrophages.In addition,combined treatments could elevate the proportion of T helper subtype 1 cells(Th1 cells)and cytotoxic T lymphocytes cells(CTLs)to mediate anti-tumor immune response in TME.Conclusion:In summary,this pre-clinical study indicated that reversing hypoxia in TME by using oxygen microcapsules was an effective strategy to improve the performances of ICB on PDAC,which holds great potential for treating PDAC in the future.

Phase separation-induced nanoprecipitation for making polymer nanoparticles with high drug loading Special Collection:Distinguished Australian Researchers

Increasing drug loading remains a critical challenge in the development and translation of nanomedicine.High drug-loading nanoparticles have demonstrated unique advantages such as less carrier material used,better-controlled drug release,and improved efficacy and safety.Herein,we report a simple and efficient salt concentration screening method for making polymer nanoparticles with exceptionally high drug loading(up to 66.5 wt%)based on phase separation-induced nanoprecipitation.Upon addition of salt,phase separation occurs in a miscible solvent-water solution delaying the precipitation time of drugs and polymers to different extents,facilitating their co-precipitation thus the formation of high drug-loading nanoparticles with high encapsulation efficiency(>90%)and excellent stability(>1 month).This technology is versatile and easy to be adapted to various hydrophobic drugs,different polymers,and solvents.This salt-induced nanoprecipitation strategy offers a novel approach to fabricating polymer nanoparticles with tunable drug loading,and opens great potentials for future nanomedicines.