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In this study, a liquid chromatographic method was developed for the fast determination of lincomycin, polymyxin and vancomycin in a preservation solution for transplants. A Kinetex EVO C18 (150 × 4.6 mm, 2.6 µm) column was utilized at 45 °C. Gradient elution was applied using a mixture of mobile phases A and B, both including 30 mM phosphate buffer at pH 2.0 and acetonitrile, at a ratio of 95:5 (v/v) for A and 50:50 (v/v) for B. A flow rate of 1.0 mL/min, an injection volume of 20 µL and UV detection at 210 nm were used. A degradation study treating the three antibiotics with 0.5 M hydrochloric acid, 0.5 M sodium hydroxide and 3% H2O2 indicated that the developed method was selective toward lincomycin, polymyxin, vancomycin and their degradation products. Other ingredients of the preservation solution, like those from the cell culture medium, did not interfere. The method was validated with good sensitivity, linearity, precision and accuracy. Furthermore, lincomycin, polymyxin and vancomycin were found to be stable in this preservation solution for 4 weeks when stored at −20 °C.

The factors affecting the bound acrylonitrile content of NBR product during the polyme-rization process were investigated, including monomer reactivity ratio, monomer conversion, monomer concentration, and polymerization temperature and pressure, the structural composition of the product was analyzed, and the polymerization reaction kinetics and repeatability experiment were carried out. The results showed that under the polymerization temperature of 5.0 ℃ and polymerization pressure of 0.15-0.20 MPa, NBR products with uniform distribution of acrylonitrile structure units and mass fraction of bound acrylonitrile of 17%-19% could be obtained by using multi-stage addition of acrylonitrile and controlling the monomer conversion of 70%-75%. The polymerization formula and process had good repeatability.

Butadiene-acrylonitrile-butylacrylate terpolymer (BNBR) was synthesized by emulsion polymerization method. The effects of amount of initiator, emulsifier and regulator of relative molecular weight on the emulsion polymerization rate were investigated. And the microstructure and dynamic mechanical properties were characterized. The results showed that the polymerization rate increased and the reaction induction period shortened with increasing polymerization temperature. The increasing amount of initiator and emulsifier could increase the reaction rate, while the change in the amount of relative molecular weight regulator had little effect on the reaction rate. The apparent activation energy of the BNBR was 27.97 kJ/mol, and the particle size distribution of BNBR latex was uniform. The glass transition temperature of BNBR was lower than that of nitrile rubber（NBR）with a difference of about 10 ℃. BNBR had better dynamic mechanical pro-perties at low temperature than NBR.

Marine anti-fouling coatings represent an efficient approach to prevent and control the marine biofouling. However, a significant amount of antifouling agent is added to improve the static antifouling performance of the coatings, which leads to an issue whereby static antifouling performance conflicts with eco-friendly traits. Herein, this work reports an in situ reduction synthesis of silver nanoparticles (AgNPs) within polymers to produce composite coatings, aiming to solve the aforementioned issue. Firstly, urushiol-based benzoxazine monomers were synthesized by the Mannich reaction, using an eco-friendly natural product urushiol and n-octylamine and paraformaldehyde as the reactants. Additionally, AgNPs were obtained through the employment of free radicals formed by phenolic hydroxyl groups in the urushiol-based benzoxazine monomers, achieved by the in situ reduction of silver nitrate in benzoxazine. Then, the urushiol-based benzoxazine/AgNPs composite coatings were prepared by the thermosetting method. AgNPs exhibit broad-spectrum and highly efficient antimicrobial properties, with a low risk to human health and a minimal environmental impact. The composite coating containing a small amount of AgNPs (≤1 wt%) exhibits effective inhibition against various types of bacteria and marine microalgae in static immersion, thereby displaying outstanding antifouling properties. This organic polymer and inorganic nanoparticle composite marine antifouling coating, with its simple preparation method and eco-friendliness, presents an effective solution to the conflict between static antifouling effectiveness and environmental sustainability in marine antifouling coatings.

This study investigated the impact of calcium chloride (CaCl2) and magnesium chloride (MgCl2) at varying concentrations on a model milk formulation’s physical and chemical properties after thermal treatment. The model milk was subjected to two-stage homogenization and pasteurization before being supplemented with different concentrations of CaCl2 or MgCl2. The findings revealed that elevating the concentration of either calcium or magnesium resulted in the milk emulsion having a higher viscosity and median particle size following heating. CaCl2 had a slightly stronger impact than MgCl2, particularly at higher concentrations. The milk samples also exhibited a reduction in the zeta potential as the ionic strength of the salt solution increased, with the CaCl2-fortified milk displaying a slightly lower negative surface charge than the MgCl2-fortified milk at the same dose. The model milk’s viscosity was evaluated after adding various salt concentrations and a temperature ramp from 20 to 80 °C. Notably, the viscosity and particle size changes demonstrated a non-linear relationship with increasing mineral levels, where a significant increase was observed at or above 5.0 mM. An emulsion stability analysis also revealed that the de-stabilization pattern of the high salt concentration sample differed significantly from its low salt concentration counterparts. These findings could serve as a basis for the future development of fortified UHT milk with nutritionally beneficial calcium and magnesium in industrial applications.

Star shaped miktoarm isoprene-butadiene-styrene rubber with high wet skid resistance and low rolling resistance was prepared by living anionic solution polymerization with n-butyl lithium as initiator, cyclohexane as solvent, sodium dodecylbenzene sulfonate/tetramethylethylenediamine as complex regulator and divinylbenzene as coupling agent, the effects of polymerization temperature and amount of complex structure regulator and coupling agent on microstructure, dynamic mechanical pro-perties and mechanical properties of the polymer were investigated. The results showed that the content of non-1,4-unit in the polymer increased gradually with increase of the amount of complex regulator, and decreased with rise of polymerization temperature. The loss factor of the polymer at 0 ℃ increased gradually with increase of the amount of complex regulator and dropping of polymerization temperature, which improved wet resistance of the polymer; The loss factor at 60 ℃ decreased gradually with increase of the amount of coupling agent, which reduced rolling resistance of the polymer. In addition, molecular weight distribution of the polymer became wider after coupled and its processability was improved.

An unprecedented N-alkylation of 3-nitroindoles with para-quinone methides was developed for the first time. Using potassium carbonate as the base, a wide range of structurally diverse N-diarylmethylindole derivatives were obtained with moderated to good yields via the protection group migration/aza-1,6-Michael addition sequences. The reaction process was also demonstrated by control experiments. Different from the previous advances where 3-nitrodoles served as electrophiles trapping by various nucleophiles, the reaction herein is featured that 3-nitrodoles is defined with latent N-centered nucleophiles to react with ortho-hydrophenyl p-QMs for construction of various N-diarylmethylindoles.

Benzoxazine resins are new thermosetting resins with excellent thermal stability, mechanical properties, and a flexible molecular design, demonstrating promise for applications in marine antifouling coatings. However, designing a multifunctional green benzoxazine resin-derived antifouling coating that combines resistance to biological protein adhesion, a high antibacterial rate, and low algal adhesion is still challenging. In this study, a high-performance coating with a low environmental impact was synthesized using urushiol-based benzoxazine containing tertiary amines as the precursor, and a sulfobetaine moiety into the benzoxazine group was introduced. This sulfobetaine-functionalized urushiol-based polybenzoxazine coating (poly(U−ea/sb)) was capable of clearly killing marine biofouling bacteria adhered to the coating surface and significantly resisting protein attachment. poly(U−ea/sb) exhibited an antibacterial rate of 99.99% against common Gram negative bacteria (e.g., Escherichia coli and Vibrio alginolyticus) and Gram positive bacteria (e.g., Staphylococcus aureus and Bacillus sp.), with >99% its algal inhibition activity, and it effectively prevented microbial adherence. Here, a dual-function crosslinkable zwitterionic polymer, which used an “offensive-defensive” tactic to improve the antifouling characteristics of the coating was presented. This simple, economic, and feasible strategy provides new ideas for the development of green marine antifouling coating materials with excellent performance.

Obesity is one of the prevalent chronic diseases in human and companion animals usually associated with several metabolic disorders. The gut commensal bacterium Akkermansia muciniphila (A. muciniphila) is known for its therapeutic effects on metabolic disorders and inflammations. Here, we isolated the A. muciniphila AKK2 strain from the feces of interferon-inducible protein 204−/− (IFI204−/−) mice and further evaluated its anti-obesity effects on high-fat diet (HFD)-fed C57BL/6J mice and beagles. The results showed that it effectively controlled weight gain. Microbiome analysis using 16S rRNA gene sequencing revealed that HFD alters gut microbiota composition and A. muciniphila AKK2 increases the Firmicutes/Bacteroidetes (F/B) ratio in beagles. Furthermore, we prepared microcapsules containing A. muciniphila AKK2, and tolerance tests showed the encapsulation maintained high viability and stability in an aerobic environment and simulated the secretion of gastrointestinal fluids. Overall, this study widens the spectrum of A. muciniphila applications to prevent obesity.

The high strength, high specific surface area, excellent biocompatibility, and degradability of nanocellulose (NCC) make it a potential reinforcing phase for composite materials. However, the polyhydroxyl property of NCC renders it prone to self-aggregation and it has weak interfacial compatibility with non-polar substrates, limiting its enhancement performance for composite materials. Therefore, based on the high reactivity of NCC, the chemical modification of NCC to introduce functional groups is the basis for effectively reducing its self-aggregation, improving its interfacial compatibility with the polymer matrix, and creating nanocellulose-based functional materials. The existing functional modifications of NCC have limitations; they require cumbersome steps, generate low yields, and are environmentally unfriendly. Herein, ureido-pyrimidinone (UPy) was introduced to NCC through a sustainable and high-efficiency avenue formed by the mechanochemical synergy of microwaves and ultrasonication. The obtained UPy-modified nanocellulose (NCC-UPy) exhibited a rod-like shape, with a length of 200–300 nm and a width of 20–30 nm, which presented oriented and stable dispersion in an aqueous medium, and the zeta potential reached −40 mV. Moreover, NCC-UPy had good thermostability (>350 °C) and high crystallinity (82.5%) within the crystal type of cellulose I. Using the as-prepared NCC-UPy as a molecular bridge, it was organically combined with epoxy resin through multiple hydrogen bonds to construct a nanocomposite membrane with superior mechanical strength and thermal stability. The results revealed that NCC-UPy dispersed uniformly in the epoxy matrix without aggregating and that the interfacial compatibility was good, leading to an 87% increase in the tensile strength of the formed nanocomposite membrane when 0.5 wt.% NCC-UPy was loaded. It was proved that NCC-UPy had remarkable reinforcing potential and effective stress transfer capacity for composites. Consequently, this study may open the door to the development of a one-pot green approach for undertaking the functional modification of NCC, and it is of great significance for the development of NCC-based nanocomposites.

Raw lacquer (RL) is a natural polymer compound with highly promising applications; however, its inflammable attribute restricts the industrial applications. In this study, melamine is used to formulate tri (1-melamine-2-propanol) phosphate (FR-1), after which it is synthesized with ammonium phosphate (FR-2) and diatomite to form a compound phosphorus-nitrogen intumescent flame retardant (IFR). Next, IFR is used as the filling agent that then cross-links with RL, and as such RL/IFR membranes are formed after the curing. The limiting oxygen index (LOI) measurement, the vertical combustion test (UL-94), the microshape calorimetric analysis (CCT), and the thermal gravimetric analysis (TGA) are conducted to examine the combustion resistance and thermal stability of the membranes. Fourier transform infrared spectroscopy (FT-IR) and electron scanning microscope (SEM) are performed to separately characterize the structure and compatibility; the mechanical properties of the membranes are also evaluated. The vertical combustion test results confirm that with 30 wt% of IFR, RL/IFR membranes acquire 12.3% higher LOI and a vertically combustion of V-0 level. The TGA indicates that RL/IFR membranes demonstrate a greater adhesion level, a higher rigidity, and better luster than pure RL membranes.

Ivalin, a natural compound isolated from Carpesium divaricatum, showed excellent microtubule depolymerization activities among human hepatocellular carcinoma in our previous work. Here, we investigated its functions on mitochondria-mediated apoptosis in hepatocellular carcinoma SMMC-7721 cells. DAPI (4′,6-diamidino-2-phenylindole) staining, annexin V-fluorexcein isothiocyanate (FITC) apoptosis detection, and western blotting were applied to explore the apoptotic effect of Ivalin. Next, the induction effect of Ivalin on the mitochondrial pathway was also confirmed via a series of phenomena including the damage of mitochondria membrane potential, mitochondria cytochrome c escape, cleaved caspase-3 induction, and the reactive oxygen species generation. In this connection, we understood that Ivalin induced apoptosis through the mitochondrial pathway and the overload of reactive oxygen species. Furthermore, we found that the activation of nuclear factor-κB (NF-κB) and subsequent p53 induction were associated with the apoptotic effect of Ivalin. These data confirmed that Ivalin might be a promising pro-apoptotic compound that can be utilized as a potential drug for clinical treatment.

A bark-like imitated polypr opylene (PP)/polycarbonate (PC) nanofibrous membrane was constructed by one-step meltblown technique for efficient particulate matter (PM) removal. The effects of PC content (0%, 1%, 3%, 5%, and 7%) on membrane thermal stability, microscopic characteristics, filtration performance, hydrophilicity, and water vapor transmission were investigated. The results demonstrated that using facile design of incompatibility and viscosity difference between PC and PP polymers decreases average fiber diameter, creating a bark-like groove appearance and increasing surface potential, making a new PP/PC membrane with high filtration performance. The resultant PP/PC membrane had finer average fiber diameter of 0.63 μm, which was nearly 89.41% lower than PP membranes (5.95 μm), and its quality factor (0.036 Pa−1) was nearly 2.12 times than that of PP membranes (0.017 Pa−1) with the die hole diameter of 0.5 mm. This fabrication technique of a special meltblown filter membrane saves the cost of die retrofitting and post-processing, which provides an innovative method for particulate efficient removal of high efficient filters.

In this article, expanded vermiculite (EV)-enhanced polyurethane foam bionic composites inspired by pomelo peel is proposed. The columnar lattice structure mold is employed to constitute the periodic interface structure and gradient foam structure, and the nylon nonwoven fabric is combined as the surface layer. The effects of EV content on the thermal, compression, and dynamic cushion properties of bionic composites are investigated. Results show that residual char increases with EV content, which conduces to decrease the release of heat flow. The proposed bionic composite with columnar lattice structure has optimal compressive modulus, energy absorption and dynamic cushion efficacy when 1 wt% EV is added. However, its performance decreases slowly when EV fillers are continuously added because the cell morphology is changed from round to irregular shape and the interfacial adhesion of filler−matrix is weakened. Owing to their unique bionic structure, composites can absorb 99% of the energy impacted by flat impactor within a smaller deformation and achieve 97% absorption efficiency for a hemispheric impactor in cushion test.

This study aims to produce polypropylene (PP)/titanium dioxide (TiO2) melt-blown membranes for oil/water separation and photocatalysis. PP and different contents of TiO2 are melt-blended to prepare master batches using a single screw extruder. The master batches are then fabricated into PP/TiO2 melt-blown membranes. The thermal properties of the master batches are analyzed using differential scanning calorimetry and thermogravimetric analysis, and their particle dispersion and melt-blown membrane morphology are evaluated by scanning electron microscopy. TiO2 loaded on melt-blown membranes is confirmed by X-ray diffraction (XRD). The oil/water separation ability of the melt-blown membranes is evaluated to examine the influence of TiO2 content. Results show that the thermal stability and photocatalytic effect of the membranes increase with TiO2 content. TiO2 shows a good dispersion in the PP membranes. After 3 wt.% TiO2 addition, crystallinity increases by 6.4%, thermal decomposition temperature increases by 25 °C compared with pure PP membranes. The resultant PP/TiO2 melt-blown membrane has a good morphology, and better hydrophobicity even in acetone solution or 6 h ultraviolet irradiation, and a high oil flux of about 15,000 L·m−2·h−1. Moreover, the membranes have stabilized oil/water separation efficiency after being repeatedly used. The proposed melt-blown membranes are suitable for mass production for separating oil from water in massively industrial dyeing wastewater.