查找使用阿拉丁产品的科研文献

Tuning the pore architecture of HKUST-1 via Polyvinylpyrrolidone for superior CH4 capture

Bin Zhou,Yanlin Chen,Zhen Wang,Haifei Lin,Haiqing Shuang,Zeyou Meng,Liang Cheng,Yi Zhang,Qiqi Yin

The structure-property relationship between MOFs and CH 4 capture was clarified. • PVP served as template and structure-directing agent to tailor the pore of HKUST-1. • PVP-assisted HKUST-1-P x display volcano-like CH 4 adsorption behavior. • GCMC simulation was used to reveal the CH 4 adsorption mechanism on different MOFs. Efficient CH 4 capture from low-concentration coal mine gas is of great significance. Metal–organic frameworks (MOFs) are promising adsorbents owing to high porosity and structural tunability. Nevertheless, regulating the relationship between the MOFs structure and CH 4 capture performance, as well as developing rational strategies to overcome the adsorption bottleneck of MOFs, remain critical challenges. Herein, we present a systematic investigation of pore environments and adsorption sites on CH 4 capture, employing representative MOFs with diverse metal centers (Zr, Zn, Fe, Co, and Cu) and different topological structures. Interestingly, HKUST-1(Cu), with a matched pore size and open-metal sites, exhibited the highest adsorption capacity. Furthermore, by leveraging polyvinylpyrrolidone(PVP)-assisted pore modulation, HKUST-1-P x exhibited concentration-dependent growth. At low PVP concentrations, it selectively modulates the growth kinetics of crystallographic facets through coordination and steric effects, whereas at high concentrations, excessive PVP preferentially forms a dense layer that stabilizes the crystal dimensions and promotes isotropic growth. Moreover, the CH 4 adsorption capacity of HKUST-1-Pₓ follows an intriguing volcano-type trend with varying PVP content. Notably, HKUST-1-P 0.4 affords the best adsorption performance—30% higher than HKUST-1. Grand Canonical Monte Carlo simulations reveal that the coordination between PVP and Cu nodes reconstructs the pore distribution of HKUST-1-P x and strengthens CH 4 binding, as evidenced by the decrease in the adsorption energy of the CH 4 molecule from −18.05 kJ/mol (HKUST-1) to −27.15 kJ/mol (HKUST-1-P 0.4 ). Finally, the cyclic and breakthrough tests further validated the application potential of HKUST-1-P 0.4. This study provides innovative polymer-induced strategies for designing high-performance CH 4 -capture adsorbents for low-concentration coal mine gas. Download: Download high-res image (203KB) Download: Download full-size image

Electrospun composite nanofibers of Sanghuangporus sanghuang polysaccharide and polyvinylpyrrolidone for assisting melanoma treatment

Wenwen Shang,Hanning Yu,Liangyu He,Xiuhua Hu,Ce Wang,Ping Hu,Yong Liu

Melanoma represents a highly aggressive malignancy with strong metastatic potential and poor prognosis. Due to the limitations of current therapies, developing more effective anticancer strategies remains urgent. Sanghuangporus sanghuang polysaccharides (SSP) exhibit antitumor activity; however, low yield and delivery efficiency hinder clinical application. This study aims to obtain high SSP yield through process optimization and to preliminarily evaluate its anti-melanoma potential by developing a nanofiber-based delivery system. Aqueous extraction was first optimized through single-factor and orthogonal experiments, followed by high-temperature extraction. The optimal high-temperature condition was 170 °C, yielding the highest polysaccharide yield (13.75 ± 0.09%) and purity (95.18 ± 0.22%). Monosaccharide analysis showed that high-temperature extraction appeared to increase the proportion of glucose. Subsequently, SSP extracted at different temperatures was electrospun with polyvinylpyrrolidone to produce composite nanofibers. The fibers exhibit favorable morphology, enhanced mechanical strength, and tunable in vitro release. Biological evaluations showed that the fiber membranes were biocompatible toward HUVECs, while inhibiting B16-F10 melanoma cell proliferation and migration. This work provides a high-efficiency extraction protocol and a preliminary nanofiber-based delivery system for assisting melanoma treatment.

Effects of polyvinylpyrrolidone and poly (ethylene glycol) on preparation of ibuprofen pharmaceutical cocrystal

Yang Xintong,Chen Yang,Qiao Ning

In this study, we investigated the effects of polymers on the pharmaceutical cocrystal formation process. Ibuprofen (IBU) was selected as the active pharmaceutical ingredient (API), nicotinamide (NIC) and saccharin (SAC) as the cocrystal coformer (CCF), ethanol/water as the solvent, polyvinylpyrrolidone (PVP) and poly (ethylene glycol) (PEG) as the representative polymers. We prepared IBU-NIC and IBU-SAC cocrystals in ethanol-water cosolvent in the absence or presence of polymers. Cocrystal screening products were characterized by FTIR, DSC, PXRD, and HPLC. The results showed that the mixture of IBU and IBU-NIC cocrystal can be prepared in ethanol-water cosolvent without polymers. The addition of PVP facilitates the formation of pure IBU-NIC cocrystal; however, no cocrystal was formed in PEG solutions. SAC could not cocrystallize with IBU in the ethanol-water solvent in the absence of polymers. Neither PVP nor PEG could facilitate the formation of the IBU-SAC cocrystal.

Carboxymethyl chitosan-grafted polyvinylpyrrolidone-iodine microspheres for promoting the healing of chronic wounds

Jie Yu,Pei Wang,Mengting Yin,Kaiwen Zhang,Xiansong Wang,Bing Han

Polyvinylpyrrolidone and graphene-modified hematite nanoparticles for efficient electrocatalytic oxidation of p-nitrophenol

Guo Yan,Li Zhuang,Wei Yuxi,Zhang Xinxu,Shi Kexin

Polyvinylpyrrolidone (PVP) and graphene (G)-modified iron oxides (Fe 2 O 3 -PVP-G) are prepared by a simple hydrothermal reaction. Their morphology and structure were examined and proved by transmission electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and ultraviolet–visible diffuse reflectance spectroscopy. P-nitrophenol (p-NP) is a usual organic pollutant, which is highly toxic and difficult to decompose. Electrochemical reduction of p-NP is a widely used treatment, but the reduction products are still toxic. In this work, the electrochemical catalytic oxidation of p-NP was achieved on Fe 2 O 3 -PVP-G modified electrodes. Compared to pure Fe 2 O 3 , Fe 2 O 3 -PVP-G shows better catalytic performance, with a current density 10.4 times larger than that from Fe 2 O 3 . Electrochemical results verify that the improvement comes from the promotion of its activity and the favorable enrichment of p-NP with the help of the doped PVP and G. pH experiments indicate that p-NP is oxidized to aliphatic acid, which is non-toxic and environmentally friendly. Due to the protection of organic molecules, Fe 2 O 3 -PVP-G exhibits long-term stabilities on electrochemical oxidation on p-NP with the retention of 88.5% for 15 days. Our results also provide another perspective for studying electrocatalytic performances.

Polyvinylpyrrolidone functionalization induces deformable structure of graphene oxide nanosheets for lung-targeting delivery

Hongyang Yu,Bing Wang,Shuang Zhou,Meilin Zhu,Wei Chen,Hanqing Chen,Xue Li,Shanshan Liang,Meng Wang,Lingna Zheng,Lina Zhao,Zhifang Chai,Weiyue Feng

Nanomaterials (NMs) as lung-targeted drug delivery vehicles have attracted great attentions. Recent studies indicated that elastic or deformable property of NMs could play a vital role in biomedical applications . Herein, polyvinylpyrrolidone (PVP) functionalized graphene oxide (GO-PVP) via a facile one-pot method and PEGylated GO (GO-PEG) nanosheets (NSs) were synthesized at room temperature . By using rare earth elemental labeling method, we quantitatively revealed that GO-PVP NSs were targeting retention in the lung that after 4 h intravenous injection, the lung/liver and lung/spleen ratios in GO-PVP treated mice were about 230-fold and 30-fold higher of those in GO-PEG treated mice, respectively, especially a considerable amount was retained in the lower respiratory tract including pulmonary interstitium and alveolar region as fibril-like shapes. The florescence imaging and in situ confocal Raman microscopy combining with laser-ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) elemental imaging analysis further confirmed that a more amount of GO-PVP than GO-PEG retention in the pulmonary interstitium. Utilizing atomic force microscopy PeakForce quantitative nanomechanical mapping technique, the nanomechanical property investigation shows that GO-PVP NSs are softer, more adhesive and deformable than GO-PEG NSs. Further, the molecular dynamics simulations illustrate that GO-PVP has deformable structure due to the hydrogen-bond interaction at basal plane between PVP and GO that cause GO-PVP surface roughness and to possess low solvent accessible surface area (SASA), comparatively, the GO-PEG owns relatively firm structure and higher SASA. This study indicates that the well dispersion property and deformable structure of GO-PVP in the lung contribute to its filtration of the endothelial/epithelial barrier and retention in the interstitium and alveolar region. Importantly, the study inspires us to design elastic or deformable NMs in response to the lung disease especially those have occurred in the lower respiratory tract.

Removal of Emulsified Oil from Aqueous Environment by Using Polyvinylpyrrolidone-Coated Magnetic Nanoparticles

Shimin Shao,Yan Li,Ting Lü,Dongming Qi,Dong Zhang,Hongting Zhao

In recent years, a large amount of emulsified oily wastewaters were produced from petroleum and food industries, resulting in severe environmental problems. In this study, a series of polyvinylpyrrolidone (PVP)-coated Fe3O4magnetic nanoparticles (MNPs) were prepared via one-step solvothermal method by introducing various amounts or types of PVP. The synthesized MNPs were characterized by multiple techniques, and their demulsification performances were evaluated in petrochemical and vegetable oil wastewaters, respectively. Results showed that the introduction of PVP in solvothermal process could significantly enhance the demulsification efficiency of MNPs, although excessive addition of PVP could not further increase its efficiency. Moreover, the effects of pH, surfactant concentration of wastewater, and the recycle number of MNPs on the demulsification performance were investigated in detail. It was found that the demulsification efficiency decreased with the increase of pH and surfactant concentration, and the synthetic MNPs were still effective after being reused for 5 cycles under acidic and neutral conditions. It is expected that the development of the PVP-coated MNPs can provide a simple and powerful route for the oily wastewater treatment.Keywords:magnetic nanoparticles;polyvinylpyrrolidone;magnetic separation;demulsification performance;reusability

Polyvinylpyrrolidone-assisted synthesis of ultrathin multi-nanolayered Cu2Nb34O87−x for advanced Li+ storage

Qing Li,Dan Zhao,Shijie Sun,Xing Zhang,Yu Zhang,Chao Li,Yifeng Cheng,Jincang Zhang,Renchao Che

The ultrathin multi-nanolayered structure with ultrathin monolayer thickness (<10 nm) and certain interlayer spacing can significantly shorten Li + paths and alleviate the volume effect for Li + -storage materials. However, unlike layered materials such as MXene and MoS 2 , shear ReO 3 -type niobates have difficulty forming ultrathin multi-nanolayered structures due to their crystal structures, which still remains a challenge. Herein, by a polyvinylpyrrolidone (PVP)-assisted solvothermal method , we first synthesize ultrathin multi-nanolayered Cu 2 Nb 34 O 87−x with oxygen vacancies composed of ultrathin nanolayers (2–10 nm in thickness) and interlayer spacing (1–5 nm). Oxygen vacancies can radically enhance the inherent electronic/ionic conductivity and Li + diffusion coefficient of this material. The PVP-induced formation mechanism of this material is expounded in detail. The well-preserved ultrathin multi-nanolayered structure and excellent multi-electron electrochemical reversibility (Nb 5+  ↔ Nb 4+  ↔N b 3+ and Cu 2+  ↔ Cu + ) of this material during cycling are fully verified. Based on an ultrathin multi-nanolayered structure and oxygen vacancies, this material as the anode of lithium-ion batteries is highly competitive among reported shear ReO 3 -type Cu-Nb-O anodes, displaying a high reversible capacity (315.3 mAh g −1 after 300 cycles at 1 C), durable cycling stability (85.7 % capacity retention after 1000 cycles at 10 C), and outstanding rate performance. Moreover, the application of this material to lithium-ion capacitors generates a large energy density (97.9 Wh kg −1 at 87.5 W kg −1 ) and a high power density (17,500 W kg −1 at 12.6 Wh kg −1 ), thus further indicating its fast faradaic pseudocapacitive behavior for practical applications. The results of this work indicate a breakthrough in synthesizing ultrathin multi-nanolayered shear ReO 3 -type niobates.

Synergistic effect of polyvinylpyrrolidone noncovalently modified graphene and epoxy resin in anticorrosion application

Shifeng Wen,Jiacheng Ma

In this article, polyvinylpyrrolidone (PVP) was used for the noncovalent modification on the surface of graphene. Compared with covalent modification, this method maintained the original structure of graphene layers, thereby maximizing the original properties of graphene. The π–π noncovalent bond was formed between PVP and graphene by X-ray photoelectron spectroscopy analysis, indicating that PVP successfully modified graphene. The thickness of graphene layer was measured by atomic force microscopy, which showed that the distance between graphene layers was increased by 5–6 nm, and the stability of the modified graphene in N,N-dimethylformamide was remarkably improved. The obtained composite coating by combination of the modified graphene and the epoxy resin was subjected to electrochemical impedance test to obtain the best anticorrosive effect of the coating with the graphene content of 0.3 wt%. The results showed that the addition of graphene to the epoxy resin could effectively improve the anticorrosive effect. Meanwhile, the good electrical conductivity allowed the electrons which lost from the substrate to led to air or saline rapidly, thereby reducing the combination of iron ions with oxygen and the generation of corrosion products (iron oxides).

Structurally ordered Pt3Co for oxygen reduction reaction prepared using polyvinylpyrrolidone as auxiliary dispersant

Qingyu Luo,Sihao Wang,Yingfang Zhu,Shaolong Tang,Youwei Du

Structurally ordered Pt3Co/C nanoparticles (NPs) were obtained via a spray paint drying method with an annealing treatment. The addition of a suitable dose of polyvinylpyrrolidone resulted in a narrow size distribution of the Pt3Co/C-600-1 NPs, an average particle size of ca. 4.6 nm, which may be due to the enhanced dispersion in aqueous solution resulting from the carbon support. The sample denoted as Pt3Co/C-600-1 NPs performs high activity for oxygen reduction reaction with the mass activity (MA) ca. 3 times higher than that of a commercial Pt/C catalyst at 0.9 V. Accelerated durability tests (ADTs) showed that Pt3Co/C-600-1 NPs exhibit superior stability with a minimal loss of 17.5% in MA at 0.9 V after 5000 cycles, while Pt/C catalysts show loss of 44.4%. This simple two-step strategy provides an effective way to prepare Pt-based catalysts for industrial application.

Polyvinylpyrrolidone-assisted in situ enzymes encapsulation within ZIF-8 for enhanced glycerol conversion

Linsong Luo,Xiao Han,Xiaoyan Dong,Qinghong Shi,Yan Sun

The growth of biodiesel and oleochemical industries results in substantial surpluses of glycerol and consistently low prices. To absorb this surplus, we report a polymer-assisted in situ enzymes encapsulation strategy in which glycerol dehydrogenase (GDH) is encapsulated with polyvinylpyrrolidone (PVP) and cysteine (Cys) within ZIF-8 for glycerol conversion. The results showed that the encapsulated GDH/ZIF-8 composites presented stronger substrate affinities and higher catalytic efficiencies than free GDH as well as good stability. Among the free GDH and GDH/ZIF-8 composites, GDH/Cys/PVP@ZIF-8 presented the highest relative activity of 300.7 %. This could be attributed to the structural evolution of the encapsulated GDH and the formation of a more hydrophilic microenvironment around GDH during complexation with PVP. To increase cofactor utilization, a cofactor self-sufficient cascade system was constructed by encapsulating GDH and forming H 2 O NADH oxidase (Nox) with PVP and Cys within ZIF-8 for the conversion of glycerol to 1,3-dihydroxyacetone (DHA). At the optimal GDH:Nox molar ratio (4:1) and a substrate concentration of 100 mM, the DHA yield reached approximately 4.2 mM in GDH-Nox/Cys/PVP@ZIF-8, and the total turnover number of GDH-Nox/Cys/PVP@ZIF-8 reached 2787 at 0.05 µM NAD + , indicating its feasibility for large-scale DHA production. This work has thus provided a promising procedure of co-immobilizing enzymes via Cys/PVP-assisted in situ encapsulation within ZIF-8 for the development of economically viable multienzyme biocatalysts for glycerol conversion.

Zn/Gallic Acid/Polyvinylpyrrolidone Coordination Polymer Nanoparticles as Sunscreen for Broadband UV Protection

Jian Chen,Huili Liu,Jing Zhang,Mengmeng Hou,Haojie Cheng,Jiaman Wu,Shouren Zhang,Baocheng Yang

Excessive ultraviolet (UV) exposure from sunlight has brought serious threats to human health. Due to their excellent UV absorption and antioxidant properties, natural polyphenols have emerged as green UV filters to replace commercial sunscreens which have alarming biosafety and serious damage to marine environments. However, the commercial application of polyphenols is greatly limited by their narrow wavelength absorption, long-term instability, and deep skin penetration. Herein, broadband UV filters with good antioxidant ability and high security were developed by coordination assembly of gallic acid and Zn2+ with combination of polyvinylpyrrolidone (PVP) (Zn-GA-PVP NPs). Owing to the π–π stacking interaction, ligand-to-metal charge transfer, and the carambola-like morphology, the UV shielding range of Zn-GA-PVP NPs is broadened to entire UVA and UVB region through both absorption and reflection of UV rays. The antioxidant ability of Zn-GA-PVP NPs is protected by PVP, which guarantees that they will negatively generate but effectively scavenge reactive oxygen species upon UV exposure. The abundant phenolic hydroxyl groups and proper particle size allow Zn-GA-PVP NPs to have strong skin adhesion but not to penetrate into the deep skin. Meanwhile, Zn-GA-PVP NPs also show good water resistance and easy mechanical removal because of the amphipathy of PVP. Zn-GA-PVP NPs exhibit a high UV protection effect and good biosafety in a photodamage mouse model. This study provides a promising approach for modifying natural polyphenols to better suit their use in commercial sunscreens.