Macromolecular Research最新文献

Acute liver failure and non-alcoholic fatty liver disease (NAFLD) are a common chronic liver disease worldwide, causing tremendous clinical burden. Despite the increasing prevalence of these life-threatening liver damages, effective medical treatment has not been established. Here, we developed a new treatment strategy based on ursodeoxycholic acid (UDCA) which is one of bile acids and effective for the liver diseases. We designed poly(ursodeoxycholic acid-oxalate) (PUOX) as a polymer prodrug of UDCA. PUOX has hydrogen peroxide (H₂O₂)-scavenging peroxalate ester bonds and could be formulated into nanoparticles. PUOX nanoparticles released UDCA in a H₂O₂-triggered manner and exerted concurrent antioxidant and anti-inflammatory effects with cytoprotective actions. In mouse models of acute liver failure and NAFLD, PUOX nanoparticles exerted highly potent therapeutic effects without noticeable toxicity. PUOX nanoparticles could be a promising approach to improve the efficacy for various H₂O₂-associated liver disease.

Graphical abstract

Poly(ursodeoxycholic acid-oxalate) (PUOX) is a H₂O₂-responsive polymeric prodrug of UDCA. PUOX nanoparticles exert potent cytoprotective effects in liver diseases such as fatty acid and drug-intoxicated acute liver failure.

Understanding microorganisms is a worthy work to gather various biological information that can directly affect human beings. However, most information is detected or measured at ex-situ conditions. In this work, we attempted to fabricate a 3D printable hydrogel-based in-situ detection system. We designed the hydrogel containing azide functionalized polyethylenglycole methacrylate (PEGMA) and fabricated the hydrogel as a 3D structure to prepare flow type detector using a 3D printer. To use hydrogel as a 3D printer filament, we enhanced viscosity via the pre-crosslinking process and added bentonite with Polyethylene glycol diacrylate (PEGDA) crosslinker with a certain proportion. Prepared hydrogel 3D structure could cultivate E.coli in a liquid culture medium. The hydrogel 3D structure has an azide group which is a useful tool to introduce additional chemical functionality via azide–alkyne click reaction. Using this process, we introduced alkyne functionalized 4-(2-pyridylazo) resorcinol (PAR). The PAR clicked hydrogel can be used as flow based sensor platform to detect i.e. various metal ions including Cu, Al, and Co ions in media.

Graphical Abstract

Schematic diagram of final concept of azide-functionalized hydrogel-based in-situ detector

New strategies for overcoming the chemical degradation of anion-exchange membranes (AEM) containing perfluoroquaternary ammonium (PFQA) ionomer using inorganic free radical scavengers are described. To be more specific, the metal-oxide–perfluorinated sulfonic acid ionomer (MO–PFSA) composite nanoparticles were synthesized and investigated their nano-redispersibility after redispersing in the PFQA solution. The effect of the PFSA equivalent weight (EW) and metal precursor selection, and nano-redispersibility of MO_x composite nanoparticles in the PFQA solution were also investigated. It was reported that MO_x composite nanoparticles prepared using cerium nitrate precursor showed the best radical scavenging performance in the presence of EW800 PFSA solution compared to other MO–PFSA composite nanoparticles.

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Mechanism of nano-redispersion of the metal-oxide–perfluorinated sulfonic acid ionomer (MO–PFSA) composite nanopowders in perfluoroquaternary ammonium (PFQA) solution

This study investigates the biodegradation behavior of a blend of poly(L-lactic acid) (PLLA) and amorphous polyhydroxyalkanoate (aPHA) (50:50 wt%) under seawater conditions for 12 weeks at 30 °C. The results revealed that the inclusion of aPHA in the blend enhanced the biodegradation of PLLA. The average molecular weight analysis indicated that the blend underwent homogeneous degradation primarily through exo-chain scission. Morphological changes observed via scanning electron microscopy demonstrated that aPHA first underwent decomposition in the blend, creating channels within PLLA that enhanced water and microorganism contact and promoted PLLA hydrolysis. The release of low-molecular-weight acids from the aPHA decomposition further facilitated PLLA hydrolysis.

Graphical abstract

The graph depicts fluctuations in the weight-average molecular weight of PLLA, the PLLA/aPHA blend, and aPHA throughout the biodegradation period under seawater conditions.

The co-delivery of paclitaxel (PTX) and curcumin (Cur) has proven to be an effective method for breast cancer treatment. However, the poor solubility of both PTX and Cur limits their bioavailability, resulting in insufficient anticancer effects. Herein, we developed a novel nanogel based on fucoidan to facilitate the co-encapsulation of PTX and Cur and improve their therapeutic effectiveness. The thermosensitive copolymer, fucoidan-pluronic F127 (Fud-F127), was synthesized and characterized by various techniques, including proton nuclear magnetic resonance (¹H-NMR), transmission electron microscopy (TEM), dynamic light scattering (DLS), and critical micelle concentration (CMC). Cur and PTX were easily loaded into the Fud-F127 nanogel (Fud-F127@Cur@PTX), with high drug loading capacity of 84.4% for Cur and 86.83% for PTX. The PTX and Cur were sustainedly released followed a Fickian diffusion mechanism and triggered at acidic pH 5.5. In vitro assessments demonstrated that Fud-F127@Cur@PTX exhibited lower cytotoxicity towards breast cancer cells (MCF-7) than Fud-F127@PTX and free PTX at the same dose, highlighting the potential of Cur in mitigating the acute toxicity of PTX. These results suggest the potential of Fud-F127 as an effective nanocarrier for the co-delivery of PTX and Cur, which aims to minimize the adverse effects associated with breast cancer treatment.

Graphical abstract

Fud-F127 nanogel system encapsulating Cur and PTX for enhanced delivery

This study presents the fabrication of polylactic acid microwell patterns using a lithography-based replica molding method for the development of three-dimensional (3D) neural cell-based assays. SH-SY5Y human neuroblastoma cells interfaced with these patterns, and cell growth and morphological characteristics were evaluated with and without an inhibitor of the rho-associated coiled-coil kinase (ROCK) signaling pathway. The results revealed that the culture systems of SH-SY5Y cells on the microwell patterns could be categorized as two-dimensional (2D), 3D, and near-two-dimensional (N2D), according to their location within a dynamic multidimensional culture system. Furthermore, the geometric features of the patterns significantly impact the efficiency of the conversion model, which was characterized by the proliferation and percentage of cells in different culture systems. The rearrangement of the microfilament cytoskeleton and morphological spreading of cells on the patterns were suppressed by the downregulation of the ROCK signaling pathway. The inhibition of the ROCK signaling pathway had a time-dependent effect on the proliferation and migration of cells on the patterned substrate, where topographical cues, cell morphology, and density played pivotal roles. Consequently, the proposed system serves as a practical model for studying the functional behaviors of neural cells by dynamically assembling multidimensional culture systems on the same platform, facilitating the development of cell-based assays.

Graphical abstract

ROCK-myosin II signaling pathway on the morphology and actin cytoskeleton of SH-SY5Y cells. Immunofluorescent staining for F-actin of FS-2D cells growing on flat substrates and N2D cells or 3D cells cultured on 100–20 μm pattern for 24 h with or without Y-27632 (d–f) and blebbistatin (g–i) treatment or without any treatment (a–c). Scale bar: 20 μm 

Targeting critical pathways of cancer cells using combination drugs is gaining significant importance as drug resistance is lowered and drug efficacy is improved even at low concentrations. Docetaxel and 5-fluorouracil are chemotherapeutic drugs prescribed for patients with solid tumours. While coated polymeric nanoparticles can combat drug resistance by sequential release of drugs, this paper proposes to encapsulate docetaxel and 5-fluorouracil in chitosan nanoparticles. To further improve the solubility of chitosan nanoparticles, they are crosslinked with polyethylene glycol using formaldehyde as crosslinker. Various techniques were used to characterize the nanoparticles. HR-SEM images indicated the formation of nanoparticles, drug loading into the chitosan nanoparticles and crosslinking of polyethylene glycol to chitosan nanoparticles. The experimental strategies were designed to evaluate the synergistic combination of the drugs in nanoparticles against AGS cell lines. It was found that the drugs loaded in chitosan nanoparticles synergistically inhibited the cell viability of AGS cells with a combination effect at 0.414. The combined effect of the drugs was even more effective, with value at 0.23 in the case of polyethylene glycol crosslinked-drug-loaded chitosan nanoparticles. The DPPH scavenging activity of drugs encapsulated in polyethylene glycol crosslinked chitosan nanoparticles was more effective at 57.39% compared to drug-alone counter parts. To further confirm the synergistic efficacy of the drugs loaded in nanoparticles in inducing apoptosis, changes were observed using acridine orange /ethidium bromide staining. Results indicated that combination effect of drugs in nanoparticles was much higher in AGS cells when compared to drug-alone incubated groups.

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CsnNps@Dtl@Flul@Peg inhibits cell proliferation by disrupting microtubule disorganization and influencing RNA and DNA damage through sustained release of the drugs from the matrix

The Stille coupling of co-oligomerizations of 2,5-dibromo-3,4-diphenyl-1,1-disubstituted-siloles (R = i-Pr, n-Hex, Ph; Ia–c) with bis(tributylstannyl)acetylene (II) in the presence of PdCl₂(PPh₃)₂ as catalyst and toluene as solvent yielded oligo[(3,4-diphenyl-1,1-disubstitued-2,5-silolene)-alt-(ethynylene)]s (R = i-Pr, n-Hex, Ph; IIIa–c) as black solids. Co-oligomeric materials IIIa–c were characterized with several spectroscopic methods: nuclear magnetic resonance, Fourier-transform infrared, and ultraviolet–visible spectroscopies. Moreover, the thermal stability and anode properties of the fabricated lithium-ion secondary battery were analyzed. Compounds IIIa–c were stable up to 180 °C without weight loss under nitrogen. The coin cells fabricated using IIIa–c as active anode materials exhibited a reversible process after the 2nd cycle in their cyclic voltammograms. The co-oligomer IIIa showed good anodic properties for lithium-ion secondary battery. With an increase in the current density from 0.1 to 0.2, 0.5, 1, 2, 5, and 10 C, the capacity decreased from 2264 to 451, 361, 318, 292, 248, and 214 mAh g⁻¹, respectively. With a decrease in the current density to 1 C, the capacity returned to 287 mAh g⁻¹ at the 33rd cycle and 309 mAh g⁻¹ at the 38th cycle, indicating a lower reduction rate and superior capacity recovery rate of 97% with respect to the initial value of 318 mAh g⁻¹. The long-cycle performance of IIIa exhibited good anodic property of charge capacities at 1 C; 1602, 494, 391, 346, 364, 435, 528, 625, and 725 mAh g⁻¹ at the 1st, 2nd, 3rd, 50th, 100th, 200th, 300th, 400th, and 500th cycles, respectively. The anodic property of the cell fabricated using the co-oligomer IIIa-Li was generally superior to those of IIIb and IIIc. Therefore, IIIa-Li has the feasibility to be used in lithium-ion secondary batteries.

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This study describes the preparation and characterization of a green and safe membrane based on a natural polymer for metal adsorption. Natural rubber-grafted-(2-hydroxyethyl methacrylate) with a special nanostructure was synthesized by graft copolymerization of 2-hydroxyethyl methacrylate (HEMA) onto the surface of natural rubber (NR) particles using tert-butylhydroperoxide/tetraethylenepentamine as initiators. Optimal conditions for achieving high conversion and grafting efficiency were identified. Characterization of the as-synthesized samples was performed using Fourier-transform infrared spectroscopy, transmission electron microscopy, thermogravimetric analysis, tensile measurement, swelling degree determination, and cytotoxicity testing. The results revealed that HEMA formed a nanoscale matrix surrounding NR particles, which improved the tensile strength, thermal resistance, and swelling degree of the as-prepared samples. Cytotoxicity testing demonstrated that the membrane was safe for human use, as it did not exhibit toxicity to Vero cells at concentrations up to 1024 µg/mL. Furthermore, the membrane displayed a high adsorption capacity toward Fe³⁺ and was well described by Koble-Corrigan isotherm model and the first–second-order kinetic equation. Moreover, the membrane demonstrated excellent recyclability maintaining its adsorption ability towards Fe³⁺ ions over five consecutive cycles. Overall, these findings may recommend the NR-HEMA membrane as a promising candidate for metal removal applications.

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The adsorption of metal ions on the natural rubber with PHEMA matrix

The silk sericin (SS) recovered from silk degumming wastewater can be used to develop carbonaceous materials for organic dye removal from wastewater. To improve the adsorption capacity of the carbonaceous adsorbents derived from SS, KOH was used as an activation agent. The maximum adsorption capacity of SS-based activated carbon on methylene blue (MB) was determined by batch adsorption experiments as 964.63 mg/g. Mathematical models of adsorption were studied to reveal the adsorption mechanism. According to adsorption kinetics analysis, a pseudo-second-order model describes the adsorption performance of SS-based activated carbon on MB more appropriately, and the adsorption process follows the Langmuir model. The activated carbon prepared from SS in this work demonstrated improved MB adsorption capacity compared with other SS-based carbonaceous materials and therefore presented prosperous application possibilities for removing organic dyes from wastewater.

Graphical abstract

Creation and application of silk sericin-derived activated carbon. The silk sericin was first enriched from the silk degumming wastewater, then was converted into activated carbon by heating and activation. The generated activated carbon was later used for the adsorption of methylene blue from aqueous solutions through electrostatic and π-π interactions