Molecular Compatibility and Hydrogen Bonding Mechanism of PES/PEI Blends

Injectable Arctium lappa polysaccharide-based composite hydrogel enhances diabetic wound healing

The slow healing of diabetic wounds remains a significant challenge. However, existing treatments often prove ineffective due to the complexity of diabetic wounds. The purpose of this study was to develop an injectable hydrogel loaded with natural polysaccharides to promote diabetic wound healing. Composite hydrogels containing different concentrations of Arctium lappa polysaccharides (ALP) were prepared. The differences in their microstructure, water content, degradation rate, rheological properties, biocompatibility, promotion of epidermal cell migration, and antibacterial properties were compared to determine the optimal ALP concentration. Additionally, a diabetic rat skin defect model was constructed to further validate the promoting effect of the ALP composite hydrogel. The results indicated that CMC/CBM/ALP hydrogels formed numerous dense and regular pores, and the addition of ALP improved the stability and water content of the gels. Among the various formulations, the composite hydrogel with 2 % ALP concentration exhibited superior biocompatibility, in vitro antibacterial properties, and effectively promoted the migration of HaCat epidermal cells. Compared to hydrogels without ALP, the ALP composite hydrogels accelerated the healing of skin wounds, promoted collagen deposition and vascularization, regulated M2 macrophage polarization, reduced inflammatory responses, and ultimately enhanced wound healing. Therefore, our study provided a feasible and effective polysaccharide-based hydrogel for treating diabetic wounds.

Fabrication of Robust GO Composite Membranes through Novel Polyether Ether Ketone Weaving Strategies for Organic Solvent Nanofiltration

Fabrication of crystalline, robust graphene oxide (GO) OSN membranes is promising yet highly challenging. Herein, we prepare a SPEEK@GO/PEEK solvent-resistant composite membrane by novel weaving strategies. Among the process, SPEEK is seen as the "line", repaired of broken small pieces of GO. This facile weaving can significantly improve the separation performance and the whole stability of the membrane and effectively remove small dyes in organic solvents. The stable composite membrane exhibited excellent performance and high solvent permeance for organic solvents (DMF, 22.71 L·m-2·h-1·bar-1; acetone, 121.77 L·m-2·h-1·bar-1). The rejection rate of Acid fuchsin (AF,585 Da) exceeded 92% in DMF. The membranes exhibited excellent stability. Even after ultrasound, solvent immersion, high temperature treatment, fouling by BSA, and a long operation process, the composite membrane still maintains its original microstructure and separation performance. Taken together, this work may provide considerations in designing high performance and robust GO membranes with a stable interface.

Fabrication and Characterization of PPSU/PES Blend Nanofiltration Membrane via VIPS‐NIPS Method for Effective Dye Rejection

Industrial effluents, including dyes, pose a threat to the environment and human health, as they are resistant to reacting with oxygen; therefore, they are rarely biodegradable. Among the various processes, nanofiltration is an attractive process for separating dyes from water due to its economic efficiency. This work represents the fabrication of poly (phenyl sulfone) (PPSU)/poly (ether sulfone) (PES) blend nanofiltration membranes through vapor‐induced phase separation (VIPS) followed by immersion precipitation. The influence of polymer blend, exposure time, and coagulation bath composition on membrane characteristics and performance was studied. Results illustrate that an increment in exposure time caused a thinner top layer and changed the cross‐section morphology from finger‐like to sponge‐like. At PPSU:PES = 50:50 blend ratio, the pore radius significantly got larger than the neat polymers' fabricated membranes. The addition of N‐methyl‐2‐pyrrolidone (NMP) in the coagulation bath causes the formation of smaller finger‐like voids at the top layers and a sponge‐like structure in the sub‐layers of membranes. The optimal conditions for the nanofiltration membrane were determined at 28 s VIPS time, an equal ratio of polymers, and pure water as the coagulation bath. Under these conditions, the distilled water permeability and Rose Bengal rejection were determined as 63.6 L/m2 h and 77.11%, respectively.

Exploring Unusual Confined Chemistry: Excited-State Proton Transfer Reaction in Supported Liquid Membrane with Deep Eutectic Solvents

Supported liquid membrane (SLM) incorporating ionic liquids (ILs) or deep eutectic solvents (DESs) offers a promising method for ion and (bio)chemical separations and CO2 capture. However, a molecular understanding of whether chemical reactions occur in these confined media is crucial. We report excited-state proton transfer (ESPT) reaction of a photoacid, HPTS, in various DES-based SLMs (pore size ∼280 nm) using steady-state and time-resolved fluorescence spectroscopy. Our findings reveal that, while the ESPT is unfavorable in bulk DESs, it occurs substantially in SLM-containing DESs. Time-resolved area normalized emission spectra (TRANES) show that ESPT time ranges from 2.6 to 7.5 ns and is greatly affected by changes in DES constituents. The results suggest that HPTS interacts with ordered DES structures formed by long-range interfacial effects in membrane pores, making it suitable for ESPT. Furthermore, it is found that the dynamics of solvent relaxation in confined DESs are significantly slower than in bulk liquids. This observation, together with a large red-edge excitation shift, supports the impact of long-range interfacial effects on the DES structure inside membrane pores. Given the task-specific properties of DESs, the incorporation of these solvents into SLM pores can be a useful strategy for investigating new chemical processes.

Constructing porous ZnFC-PA/PSF composite spheres for highly efficient Cs+ removal

Radioisotope leaking from nuclear waste has become an intractable problem due to its gamma radiation and strong water solubility. In this work, a novel porous ZnFC-PA/PSF composite sphere was fabricated by immobilization of ferrocyanides modified zinc phytate into polysulfone (PSF) substrate for the treatment of Cs-contaminated water. The maximum adsorption capacity of ZnFC-PA/PSF was 305.38 mg/g, and the removal efficiency of Cs+ was reached 94.27% within 2 hr. The ZnFC-PA/PSF presented favorable stability with negligible dissolution loss of Zn2+ and Fe2+ (< 2%). The ZnFC-PA/PSF achieved high-selectivity towards Cs+ (Kd = 2.24×104 mL/g) even in actual geothermal water. The adsorption mechanism was inferred to be the ion-exchange between Cs+ and K+. What's more, ZnFC-PA/PSF worked well in the fixed-bed adsorption (E = 91.92%), indicating the application potential for the hazardous Cs+ removal from wastewater.