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Amphiphilic block copolymers are characterized by the presence of distinct hydrophilic and hydrophobic regions, which are usually arranged in alternating blocks. This unique structure allows these copolymers to self‐assemble into well‐defined nanostructures that exhibit remarkable resistance to enzymatic hydrolysis, high biocompatibility and the ability to be customized with specific structures. These properties make them highly desirable in various applications. Self‐assembled amphiphilic polypeptoids are currently under development as a promising class of pharmaceutical agents. However, the utilization of these peptides as drug carriers for efficient delivery presents a number of challenges. These challenges include less‐than‐optimal loading efficacy and restricted biocompatibility. Herein, a series of stable amphiphilic block copolypeptoids (PNEG‐b‐PNBG and PNEG‐b‐PNHG) were designed and synthesized by controlled ring‐opening polymerization. PNEG chain segments provide hydrophilicity, while PNBG and PNHG chain segments provide hydrophobicity. The hydrophobic molecular chains aggregate in aqueous solutions, resulting in the formation of nano‐assemblies. The self‐assembled amphiphilic block polypeptoid copolymers were investigated. The morphologies of copolymers take the form of micelles from tens of nanometers to a few hundred nanometers. The properties of amphiphilic block copolypeptoids used as drug carriers were further investigated by conducting drug release and cytotoxicity tests. The results indicate that the cumulative release efficiency of self‐assembled polypeptoid copolymers can reach up to about 91%. And they have good biocompatibility and can be expected to be safe materials for efficient drug delivery. This work could provide a facile method for the preparation of amphiphilic block peptoid copolymers for biopharmaceutical applications. © 2024 Society of Industrial Chemistry. [ABSTRACT FROM AUTHOR]

In this study, a thermal-responsive triblock polypeptoid, poly(N-octylglycine)-b-poly(N-allylglycine)-b-poly(N-methylglycine) (PNOG-b-PNAG-b-PNMG), was synthesized via continuous polymerization of octyl-N-carboxyanhydride (Oc-NCA), allyl-N-carboxyanhydride (Al-NCA), and methyl-N-carboxyanhydride (Me-NCA) by using benzylamine as the initiator. Remarkably, triblocks were self-assembled into micelles in an aqueous solution. The poly(N-octyl glycine) PNOG blocks form the core of the micelle, while poly(N-methyl glycine) PNMG blocks form a hydrophilic shell. The PNAG block, located between the PNOG and PNMG blocks, is soluble in water and forms part of the hydrophilic shell at low temperatures but becomes hydrophobic and associates with the micelle core at high temperatures. The micelle size transition temperature can be adjusted by changing the polypeptoid structures within the range of 35–38°C. We also systematically investigated the degree of polymerization of polymers and the effect of concentration on assembly. The antibacterial (ciprofloxacin (Cip) drug, is encapsulated in micelles through hydrophobic interactions and released in stages by adjusting the size of the hydrophobic core through temperature changes. [ABSTRACT FROM AUTHOR]

It is difficult to assess the temperature and pressure resistance of the existing soluble bridge plug seal ring used in fracking for shale gas reservoirs, to go with its high plasticity and good solubility. To overcome this shortcoming, aluminium matrix composites with the addition of 0%, 0.5% and 1.0% of graphene were prepared by spark plasma sintering. Uniaxial static pressure test results show that the composite has the maximum compressive strength and compression ratio when the graphene content is 0.5%. Microporous copper coatings were prepared on graphene/1070 aluminium surface by electroless plating. The synergistic effect of the surface microporous copper coating and the internal graphene on the corrosion performance of 1070 aluminium alloy was analysed by the weight loss and electrochemical methods. The results showed that the surface microporous copper coatings could significantly improve the uniform corrosion rate and pitting depth of graphene/1070 aluminium. [ABSTRACT FROM AUTHOR]

Developing high-performance and low-cost protein purification materials is of great importance to meet the demands for highly purified proteins in biotechnological industries. Herein, a facile strategy was developed to design and construct high-efficiency protein absorption and separation media by combining aerogels' molding techniques and impregnation processes. Poly (ethylene-co-vinyl alcohol) (EVOH) nanofibrous aerogels (NFAs) were modified by grafting butane tetracarboxylic acid (BTCA) over them in situ. This modification was carried out using polyphosphoric acid as a catalyst. The resulting EVOH/BTCA NFAs exhibited favorable comprehensive properties. Benefiting from the highly interconnected porous structure, good underwater compressive properties, and abundant absorption ligands, the obtained EVOH/BTCA NFAs possessed a high static absorption capacity of 1082.13 mg/g to lysozyme and a short absorption equilibrium time of about 6 h. A high saturated dynamic absorption capacity for lysozyme (716.85 mg/g) was also realized solely by gravity. Furthermore, EVOH/BTCA NFAs displayed excellent reusability, good acid and alkaline resistance, and unique absorption selectivity performance. The successful synthesis of such aerogels can provide a potential candidate for next-generation protein absorbents for bio-separation and purification engineering. [ABSTRACT FROM AUTHOR]

Polypeptoids with well-designed structures have the ability to self-assemble into nanomaterials, which have wide potential applications. In this study, a series of diblock copolypeptoids were synthesized via ring-opening polymerization followed by click chemistry and exhibited both temperature and pH stimulation responsiveness. Under specific temperature and pH conditions, the responsive blocks in the copolypeptoids became hydrophobic and aggregated to form micelles. The self-assembly process was monitored using the UV-Vis and DLS methods, which suggested the reversible transition of free molecules to micelles and bigger aggregates upon instituting temperature and pH changes. By altering the length and proportion of each block, the copolypeptoids displayed varying self-assembly characteristics, and the transition temperature could be tuned. With good biocompatibility, stability, and no cytotoxicity, the polypeptoids reported in this study are expected to be applied as bionanomaterials in fields including drug delivery, tissue engineering, and intelligent biosensing. [ABSTRACT FROM AUTHOR]

The development of nontoxic and efficient antifreeze agents for organ cryopreservation is crucial. However, the research remains highly challenging. In this study, we designed and synthesized a series of peptoid oligomers using the solid-phase submonomer synthesis method by mimicking the amphiphilic structures of antifreeze proteins (AFPs). The obtained peptoid oligomers showed excellent antifreeze properties, reducing the ice crystal growth rate and inhibiting ice recrystallization. The effects of the hydrophobicity and sequence of the peptoid side chains were also studied to reveal the structure–property relationship. The prepared peptoid oligomers were detected as non-cytotoxic and considered to be useful in the biological field. We hope that the peptoid oligomers presented in this study can provide effective strategies for the design of biological cryoprotectants for organ preservation in the future. [ABSTRACT FROM AUTHOR]

The design and construction of high-performance protein absorbents are of great significance for obtaining highly purified proteins in the field of biotechnology and more. In this study, the highly carboxylated absorption media were fabricated for selective absorption of positively charged proteins by using bacterial cellulose (BC) nanofibrous aerogel (NFA) as a substrate material in concert with citric acid (CA). The obtained BC/CA NFAs exhibited highly interconnected open porous structure, surface hydrophilicity, large specific surface area (14.2 m2/g), good elasticity and compression fatigue resistance. BC/CA NFAs displayed a high lysozyme absorption capacity of 868.9 mg/g and fast equilibrium within 2.5 h. A dynamic lysozyme absorption capacity of 655.35 mg/g was achieved under the drive of gravity, meeting the demands of actual applications. Furthermore, BC/CA NFAs exhibited unique absorption selectivity performance, good reusability, as well as acid and alkaline resistance. A successful scale-up of such environmental friendliness, low cost and good reproducibility absorbents could provide a new perspective to develop next generation three-dimensional chromatographic media for substantial bio-separation applications. [ABSTRACT FROM AUTHOR]

Modified polyepoxysuccinic acid (PESA-IA) was prepared by grafting itaconic acid (IA) on polyepoxysuccinic acid (PESA), which was applied to inhibit the formation of calcium carbonate (CaCO3) scale in oilfield environment. The increase of the carboxylic acid group enhances the chelating effect on calcium ions, which leads to the inhibition effect. The effects of temperature, scale inhibitor concentration and salt content on scale inhibition performance were investigated. The results show that in the static scale inhibition experiment, PESA-IA has good inhibition effect on CaCO3 scale sample, and the scale inhibition efficiency increases gradually as the temperature decreases and the concentration increases. When the temperature is 50 ℃ and the concentration is 100 mg/L, the scale inhibition efficiency reaches 98.84%. When the temperature is 70 ℃ and the concentration is 60 mg/L, the inhibition effect of scale inhibitor on CaCO3 scale increases with the salt content. The effect showed a trend of first increasing and then slightly decreasing, reaching a maximum value of 84.78% at 16 g/L, and the scale inhibition performance of PESA-IA was significantly better than that of PESA improved by 13.6%. The morphology, structure and composition of the scale samples were characterized and analyzed by scanning electron microscopy and EDS energy spectroscopy. Molecular dynamics (MD) method was used to simulate the interaction between PESA-IA and CaCO3 crystalline surface at different temperatures. The results show that the binding energy decreases as the temperature of the system increases, and the reaction between polymer molecules and CaCO3 crystals in the system can be seen by increasing the time step and the concentration of water molecules in X, Y, Z direction, and the calculated results are consistent with the experimental phenomena. [ABSTRACT FROM AUTHOR]

Developing high-performance, low-cost and large-scale absorbent materials is crucial for the treatment of water pollution caused by pollutants leakage and emission. Herein, superelastic and superhydrophobic thermoplastic polymeric nanofibrous aerogels (NFAs) were created for removal pollutants from water by using a facile and effective method. Poly(vinyl alcohol-co-ethylene) (EVOH) nanofibers fabricated by mass-production techniques were used to construct three-dimensional NFAs through combing freeze-drying process and cross-linking treatment. The optimal parameters for creating EVOH NFAs with good formability and resilience, including composition and ratio of dispersion, dosage of cross-linking agent were obtained through experiments. EVOH nanofibers bonded with each other by glutaraldehyde under acidic conditions to from fibrous network structure in EVOH NFAs. The silane-coated EVOH NFAs were prepared through further modification with vapor-phase methyltrichlorosilane. The deposition of siloxane improved mechanical strength and decreased plastic deformation after 500 cyclic compressions. An asperate fibrous and granular siloxane coating was deposited on the surface of EVOH NFAs. The surface water contact angle increased from 104.4° ± 4.0° to 152.7° ± 1.9°, wettability of NFAs transitioned to being superhydrophobic. Silane-coated EVOH NFAs exhibited superior absorption capacity (40–92 g/g) for a variety of organic pollutants. The organic pollutants would be collected and the sorbents could be reused after distillation or squeezing. A successful scale-up of such materials open up a new insight into design polymeric aerogels in low-cost and large-scale with substantial industrial water purification applications. [ABSTRACT FROM AUTHOR]