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Polymersomes have been studied for many years since their discovery, and have consistently been an appealing and widely explored research domain. Their inherent benefits, encompassing stability, versatility, load-carrying capacity, and deformability, endow them with many opportunities to be used in numerous fields of biomedicine, nanocarriers, diagnostics and therapeutics. Nevertheless, shape transformation pathways have not been comprehensively summarized or received adequate scholarly attention. Herein, we summarize typical mechanisms underlying polymersome self-assembly with a particular focus on the shape transformation pathways associated with commonly employed self-assembling methods. Moreover, we provide a succinct overview of the proposed applications involving shape transformation applications, and enumerate the most recent findings in this domain. [ABSTRACT FROM AUTHOR]

Transparent soil (TS) presents immense potential for root phenotyping due to its ability to facilitate high-resolution imaging. However, challenges related to transparency, mechanical properties, and cost hinder its development. Herein, we introduce super-transparent soil (s-TS) prepared via the droplet method using low acyl gellan gum and hydroxyethyl cellulose crosslinked with magnesium ions. The refractive index of the hydroxyethyl cellulose solution (1.345) closely aligns with that of water (1.333) and the low acyl gellan gum solution (1.340), thereby significantly enhancing the transmittance of hydrogel-based transparent soil. Optimal transmittance (98.45%) is achieved with polymer concentrations ranging from 0.8 to 1.6 wt.% and ion concentrations between 0.01 and 0.09 mol·L−1. After 60 days of plant cultivation, s-TS maintains a transmittance exceeding 89.5%, enabling the detailed visualization of root growth dynamics. Furthermore, s-TS exhibits remarkable mechanical properties, withstanding a maximum compressive stress of 477 kPa and supporting a maximum load-bearing depth of 186 cm. This innovative approach holds promising implications for advanced root phenotyping studies, fostering the investigation of root heterogeneity and the development of selective expression under controlled conditions. [ABSTRACT FROM AUTHOR]

Fuel‐driven chemical reaction networks provide an opportunity to develop chemical systems that operate out‐of‐equilibrium. There remains a need to design and develop new fuel‐driven chemical reaction networks capable of repeated operation using simple and benign chemistry. Herein, we propose a new chemical reaction network for fuel‐driven transient formation of covalent bonds, based on redox‐controlled conjugate addition and elimination chemistry. By investigating the separate reactions making up the cycle, we find that the bond formation, breaking and regeneration processes can be realized. At present, substantial side reactivity prevents achieving repeated operation of a full cycle in a single system. If such obstacles would be overcome, this chemical reaction network could be a valuable addition to the toolbox for out‐of‐equilibrium systems chemistry. [ABSTRACT FROM AUTHOR]

Ionic liquids and poly(ionic liquid)s have been successfully converted into nitrogen-doped porous carbons with tunable surface area up to 1200 m²/g at high temperatures in air. Compared to conventional carbonization process conducted under inert gas to produce nitrogen-doped carbons, the new production method was completed in a rather shorter time without noble gas protection. [ABSTRACT FROM AUTHOR]

This paper reports on the synthesis of a new type of ionic polymers, including poly(ionic liquid)s, which contain 4-methylthiazolium-based ionic liquid pending groups along the polymer chain. The monomers were prepared via simple quaternization reaction of 4-methyl thiazole with 4-vinylbenzyl chloride and the subsequentanion exchange with various anions. Free radical polymerization and anion exchange reactions were employed to prepare several 4-methylthiazolium-based ionic polymers. These polymers show anion-dependent tuneable solubility in water and organic solvents. In addition, the new polycations' ability to stabilize single-walled as well as multi-walled carbon nanotubes in water and acetone is presented. [ABSTRACT FROM AUTHOR]

The synthesis of poly(ionic liquid) (PIL) nanoparticles grafted with a poly( N-isopropyl acrylamide) (PNIPAM) brush shell is reported, which shows responsiveness to temperature and ionic strength in an aqueous solution. The PIL nanoparticles are first prepared via aqueous dispersion polymerization of a vinyl imidazolium-based ionic liquid monomer, which is purposely designed to bear a distal atom transfer radical polymerization (ATRP) initiating group attached to the long alkyl chain via esterification reaction. The size of the PIL nanoparticles can be readily tuned from 25 to 120 nm by polymerization at different monomer concentrations. PNIPAM brushes are successfully grafted from the surface of the poly(ionic liquid) nanoparticles via ATRP. The stimuli-responsive behavior of the poly(ionic liquid) nanoparticles grafted with PNIPAM brushes (NP -g-PNIPAM) in aqueous phase is studied in detail. Enhanced colloidal stability of the NP- g-PNIPAM brush particles at high ionic strength compared to pure PIL nanoparticles at room temperature is achieved. Above the lower critical solution temperature (LCST) of PNIPAM, the brush particles remain stable, but a decrease in hydrodynamic radius due to the collapse of the PNIPAM brush onto the PIL nanoparticle surface is observed. [ABSTRACT FROM AUTHOR]

Sugar-based molecules and polysaccharide biomass can be turned into porous functional carbonaceous products at comparably low temperatures of 400 °C under a nitrogen atmosphere in the presence of an ionic liquid (IL) or a poly(ionic liquid) (PIL). The IL and PIL act as “activation agents” with own structural contribution, and effectively promote the conversion and pore generation in the biomaterials even at a rather low doping ratio (7 wt%). In addition, this “induced carbonization” and pore forming phenomenon enables the preservation of the biotemplate shape to the highest extent and was employed to fabricate shaped porous carbonaceous materials from carbohydrate-based biotemplates, exemplified here with cellulose filter membranes, coffee filter paper and natural cotton. These carbonized hybrids exhibit comparably good mechanical properties, such as bendability of membranes or shape recovery of foams. Moreover, the nitrogen atoms incorporated in the final products from the IL/PIL precursors further improve the oxidation stability in the fire-retardant tests. [ABSTRACT FROM AUTHOR]

A brush type nanomotor was fabricated via assembly assistant polymerization of poly(ionic liquid) and surface grafting polymerization. The method for large-scale fabrication of brush nanomotors with soft surfaces is described. These soft locomotive particles are based on core-shell brush nanoparticles assembled from poly(ionic liquid) as core and thermoresponsive PNIPAM as brush shells on which platinum nanoparticle (PtNP) were grown in situ. The particles show non-Brownian motion in H2O2 solution. [ABSTRACT FROM AUTHOR]

Plant roots are highly sensitive to physical stress in the soil, with appropriate mechanical impedance promoting root elongation and lateral root growth. However, few studies have quantitatively explored the relationship between the mechanical impedance of the growth medium and the phenotypes of plant roots. In this study, we used a tensile machine equipped with a self-made steel needle mimicking the root tip to measure the force needed to penetrate the hydrogel medium (agar, low acyl gellan gum, and κ-carrageenan), providing insights into the force required for the rapeseed root tip to enter the medium following germination. These findings indicate that root penetration length is inversely associated with the mechanical strength of the growth medium, with variations observed in the root system adaptability across different substrates. Specifically, when the gel puncture resistance of the culture medium without adding MS reached approximately 18.4 mN, root penetration and growth were significantly hindered. With the addition of 1/2 MS medium, the polysaccharide concentration is 1.0 wt %, which is more suitable for cultivating rapeseed. This research not only offers a method for quantifying root phenotypes and medium mechanical impedance but also presents an approach for plant growth regulation and crop breeding.

Reshaping polymersomes remains a challenge for both size and shape control, methodology development, and mechanism understanding, which hindered their application in nanomedicine and nanomachine. Unlike liposome, polymersomes are capable of maintaining their shape due to their rigid and glassy membrane. Here we use the Hofmeister effect to guide the shape control of polymersome by tuning the ion type and concentration. Multiple morphologies such as ellipsoid, tube, disc, stomatocytes, and large compound vesicles are found. These results give evidence of demonstrating that the shape changes are not only induced by osmotic pressure, but also by the interaction with the polymersome membranes. Additionally, this methodology provides a general tool to tailor the shape of polymersome into various morphologies.

Polymersomes are a class of artificial liposomes, assembled from amphiphilic synthetic block copolymers, holding great promise toward applications in nanomedicine. The diversity in polymersome morphological shapes and, in particular, the precise control of these shapes, which is an important aspect in drug delivery studies, remains a great challenge. This is due to a lack of general methodologies that can be applied and the inability to capture the morphologies at the nanometer scale. Here, we present a methodology that can accurately control the shape of polymersomes via the addition of polyethylene glycol (PEG) under nonequilibrium conditions. Various shapes including spheres, ellipsoids, tubes, discs, stomatocytes, nests, stomatocyte-in-stomatocytes, disc-in-discs, and large compound vesicles (LCVs) can be uniformly captured by adjusting the water content and the PEG concentration. Moreover, these shapes undergo nonequilibrium changes in time, which is reflected in their phase diagram changes. This research provides a universal tool to fabricate all shapes of polymersomes by controlling three variables: water content, PEG concentration, and time. The use of the biofriendly polymer PEG enables the application of this methodology in the field of nanomedicine.

Accurate control of the shape transformation of polymersome is an important and interesting challenge that spans across disciplines such as nanomedicine and nanomachine. Here, we report a fast and facile methodology of shape manipulation of polymersome via out-of-equilibrium polymer self-assembly and shape change by chemical addition of additives. Due to its increased permeability, hydrophilicity, and fusogenic properties, poly(ethylene oxide) was selected as the additive for bringing the system out of equilibrium via fast addition into the polymersome organic solution. A new shape, stomatocyte-in-stomatocyte (sto-in-sto), is obtained for the first time. Moreover, fast shape transformation within less than 1 min to other relevant shapes such as stomatocyte and large compound vesicles was also obtained and accurately controlled in a uniform dispersion. This methodology is demonstrated as a general strategy with which to push the assembly further out of equilibrium to generate unusual nanostructures in a controllable and fast manner.

Self-propelled catalytic micro- and nanomotors have been the subject of intense study over the past few years, but it remains a continuing challenge to build in an effective speed-regulation mechanism. Movement of these motors is generally fully dependent on the concentration of accessible fuel, with propulsive movement only ceasing when the fuel consumption is complete. Here we report a demonstration of control over the movement of self-assembled stomatocyte nanomotors via a molecularly built, stimulus-responsive regulatory mechanism. A temperature-sensitive polymer brush is chemically grown onto the nanomotor, whereby the opening of the stomatocytes is enlarged or narrowed on temperature change, which thus controls the access of hydrogen peroxide fuel and, in turn, regulates movement. To the best of our knowledge, this represents the first nanosized chemically driven motor for which motion can be reversibly controlled by a thermally responsive valve/brake. We envision that such artificial responsive nanosystems could have potential applications in controllable cargo transportation.

We report the self-assembly of a biodegradable platinum nanoparticle-loaded stomatocyte nanomotor containing both PEG-b-PCL and PEG-b-PS as a potential candidate for anticancer drug delivery. Well-defined stomatocyte structures could be formed even after incorporation of 50% PEG-b-PCL polymer. Demixing of the two polymers was expected at high percentage of semicrystalline poly(ε-caprolactone) (PCL), resulting in PCL domain formation onto the membrane due to different properties of two polymers. The biodegradable motor system was further shown to move directionally with speeds up to 39 μm/s by converting chemical fuel, hydrogen peroxide, into mechanical motion as well as rapidly delivering the drug to the targeted cancer cell. Uptake by cancer cells and fast doxorubicin drug release was demonstrated during the degradation of the motor system. Such biodegradable nanomotors provide a convenient and efficient platform for the delivery and controlled release of therapeutic drugs.

A cationic polyelectrolyte based on the styrenic ionic liquid tributyl-4-vinylbenzylphosphonium pentanesulfonate was found to undergo a lower critical solution temperature (LCST)-type phase transition in aqueous solutions. This phase transition occurs in a wide temperature range in terms of polymer concentration as well as type and concentration of externally added salts. Anion exchange and salting out effects are responsible for the flexible phase transition temperature.