Polymers
·
2022
·Vol. 14
·期 13
·2655
·
IF 4.967
Hao Fu,Linbo Gong,Shuling Gong
This work first synthesized a series of linear polyesters by step-growth polycondensation, then an amino-terminated hydrophilic polyether was grafted to the polyester as side-chains through aza-Michael addition to prepare a self-dispersible, non-ionic waterborne comb-like polyester (NWCPE). In contrast to traditional functionalization methods that usually require harsh reaction conditions and complex catalysts, the aza-Michael addition proceeds efficiently at room temperature without a catalyst. In this facile and mild way, the NWCPE samples with number-average molecular weight (Mn) of about 8000 g mol−1were obtained. All dispersions showed excellent storage stability, reflected by no delamination observed after 6 months of storage. The NWCPE dispersion displayed better hydrolysis resistance than an ionic waterborne polyester, as was indicated by a more slight change in pH value andMnafter a period of storage. In addition, the film obtained after the NWCPE dispersion was cross-linked with the curing agent, it exhibited good water resistance, adhesion, and mechanical properties.Keywords:aza-Michael addition;comb-like polymer;non-ionic waterborne polyester;hydrolysis resistance
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED SURFACE SCIENCE
·
2021
·
IF 6.707
Xiaohan Yang,Hanbin Liu,Liwei Qian,Qingjun Meng,Haiwei Wu,Zhijian Li,Hongwei Zhou
The remediation of water that polluted by organic dyes and nanoparticles (NPs) remains a great challenge. However, second pollution of solid waste may produce if the adsorbents are not degradable or recyclable. The stimuli-responsive materials were regarded to be able to resolve this problem by reversible adsorption-desorption under stimuli. Here in this work, the surface of cellulose fibers was modified with CO 2 -responsive molecules through a simple esterification followed by an aza-Michael addition reaction. The chemical structure was confirmed with Fourier transform infrared spectra (FT-IR), X-ray photoelectron spectroscopy (XPS), x-ray diffractometer (XRD) and thermal analysis. The gas-responsiveness was demonstrated by monitoring of the pH, conductivity and surface zeta potential. Anionic dyes and negative charged NPs in water can be selectively and reversibly captured by the CO 2 -responsive surface on cellulose fibers, suggesting the inexpensive, readily available and smart cellulose fibers may find great potential in water remediation.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
Nano Research
·
2021
·Vol. 15
·期 1
·716-727
·
IF 8.897
Zhao Meijiao,Zeng Qin,Li Xipeng,Xing Da,Zhang Tao
Tumor oxygen spatial heterogeneity is a critical challenge for the photodynamic inhibition of solid tumors. Development of an intelligent nanoagent to initiate optimal therapeutics according to the localized oxygen levels is an effective settlement. Herein, we report an activatable nanoagent (BDP-Oxide nanoparticles (NPs)) to enable the oxygen auto-adaptive photodynamic/photothermal complementary treatment. Upon the nanoagent accumulated in the tumor region, the low extracellular pH could trigger the disassociation of the nanoagent to release the phototheranostic agent, BDP-Oxide, which will subsequently afford the fluorescence imaging-guided photodynamic oxidation after it gets into the outer oxygen-rich tumors. Along with the penetration deepening in the solid tumor, furthermore, BDP-Oxide could be reduced into BDP by the cytochrome P450 (CYP450) enzymes activated in the low oxygen tension regions of inner hypoxic tumors, which will switch on the photothermal and photoacoustic effects. Overall, the BDP-Oxide NPs-enabled photodynamic/photothermal complementary therapy significantly suppressed the solid tumor growth (inhibition rate of 94.8%). This work proposes an intelligent platform to address the oxygen partial pressure for the optimization of cancer phototherapeutics.
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 72
·58798-58803
·
IF 3.84
Wei He,Zheng Fang,Zhao Yang,Dong Ji,Kai Guo
The first direct aza-Diels–Alder reaction catalyzed using phosphotungstic acid combined with a water absorption device in a micro-flow system was reported. The optimization process gave azabicyclo[2.2.2]octan-5-ones in 98.78% conversion and an endo/exo ratio of 7/93. Exo cycloadducts were quickly prepared due to efficient mixing and heat transfer in the micro-flow system. However, exo products could be turned into endo cycloadducts which were more stable.
研究领域:
有机化学
·
催化化学
✓ 已验证
DOI
高影响因子
BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS
·
2020
·
IF 2.985
Yafei Wang,Huimin Liu,Jianmin Wu,Yunjian Liao,Daifeng Lu,Feng Dong,Hongxi Li,Zhitao Zhang,Yongyun Lian
Periprosthetic osteolysis (PIO) caused by wear particles is the main cause of implant failure, which is regulated by nuclear factor κ B receptor activator ligand (RANKL)/osteoprotegerin (OPG) system. At present, there is a lack of effective drugs to prevent or treat PIO. Previous studies have confirmed that DNA methylation is closely related to postmenopausal osteoporosis and can affect the expression of OPG and RANKL . However, the relationship between DNA methylation and PIO is not clear. In this study, we investigated the inhibitory effect of 5-Aza-2-deoxycytidine (AzadC) on osteolysis induced by titanium particles in a mouse model. This inhibition mechanism is achieved by changing the ratio of RANKL/OPG in the osteolysis model. In conclusion, there is a relationship between DNA methylation and PIO. AzadC has a certain inhibitory effect on osteolysis induced by titanium particles. Regulating DNA methylation may be a new way to treat PIO. Our findings lay a foundation for epigenetic understanding and intervention of osteolysis.
研究领域:
骨科
·
表观遗传学
·
生物材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CELL BIOLOGY INTERNATIONAL
·
2022
·Vol. 46
·期 11
·1900-1914
·
IF 4.473
Bin Xie,Feng Peng,Fengping He,Yixing Cheng,Jiangtao Cheng,Zhibing Zhou,Wei Mao
Ras-association domain family 1A (RASSF1A) is one of the most methylated genes in lung cancer (LC). We investigate whether the high DNA methylation level of RASSF1A can relieve the resistance of RASSF1A to LC by inhibiting RASSF1A's transcription factor binding to RASSF1A. RASSF1A expression in tissues and cells was tested utilizing quantitative real-time polymerase chain reaction (qRT-PCR), and Western blot. RASSF1A expression and RASSF1A methylation level in LC cells exposed to 5-Aza-dc were assessed by qRT-PCR and quantitative methylation-specific PCR. The association between CTCF and RASSF1A was assessed using hTFtarget, ChIP, and luciferase reporter gene analysis. The effects of 5-Aza-dc, CTCF, and RASSF1A on cell biological behaviors and epithelial-mesenchymal transition (EMT)-related markers were assessed by cell function experiments and Western blot. Moreover, we constructed the xenograft tumor and pulmonary nodule metastasis models, and assessed tumor volume and weight. RASSF1A expression and pulmonary nodule metastasis were tested utilizing qRT-PCR, Western blot, and H&E staining. RASSF1A was under-expressed in LC tissues and cells. 5-Aza-dc enhanced RASSF1A level and weakened RASSF1A methylation level in LC cells. RASSF1A silencing neutralized 5-Aza-dc-mediated repressing effects on LC cell biological function and EMT. The loss of CTCF binding to RASSF1A in LC cells was associated with DNA methylation. The effect of 5-Aza-dc on RASSF1A level, LC cell malignant behaviors, and EMT-related factors were strengthened by CTCF upregulation. RASSF1A overexpression suppressed LC tumor growth and pulmonary nodule metastasis in vivo. DNA methylation blocked the modulation of RASSF1A expression by CTCF and relieved the resistance of RASSF1A to LC.
研究领域:
癌症生物学
·
分子生物学
·
表观遗传学
✓ 已验证
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Chen Liang,Jingjing Cui,Yongding Sun,Zhe Lu,Fukang Liu,Shiwei Feng,Guang Hu,Jin Cui,Biao Zhang
Digital light processing (DLP)-based 3D printing of hydrogels with sophisticated structures has been widely used in myriads of fields. However, the inherent covalently crosslinked network of hydrogels limits their further applications, such as working as sacrificial molds. In this work, a photocurable hydrogel system with labile covalent bonds suitable for DLP based printing to fabricate 3D complex hydrogel structures with fast- and controlled degradation ability is reported. The hydrogel precursor is composed of polyethylene glycol 400 (PEG400), a water soluble photoinitiator, and PEGDA575-Do, a degradable photocurable diacrylate monomer that can be degraded in aqueous condition via reversable aza-Michael addition reaction. The mechanical properties of formed hydrogels can be regulated by changing the PEG content and water content, and the degradation rate can be regulated by changing parameters such as PEG400 content, water content and the treating temperature. Moreover, the DLP printed degradable hydrogels networks can be used as sacrificial molds to fabricate structures from materials that cannot be directly used for DLP 3D printing (e.g. thermoplastic polycaprolactone (PCL), epoxy-based resin, and chocolate). As proofs-of-concept, a microfluidic chip is fabricated by using the biocompatible 3D printed hydrogel as a sacrificial template. Similarly, a flexible RFID tag and a flexible self-powered device are also prepared, demonstrating the potential applications in the field of flexible electronics.
研究领域:
材料科学
·
生物医学工程
·
柔性电子学
✓ 已验证
产品关联
DOI
高影响因子
Gels
·
2026
·Vol. 12
·期 1
·78
·
IF 5.3
Teng Long,Ayoub El Idrissi,Lin Fu,Yufan Liu,Banlian Ruan,Minghong Ma,Zhongxun Li,Lingbin Lu
Developing sustainable and molecularly selective adsorbents for heavy-metal removal remains a critical challenge in water purification. Herein, we report a green molecular-engineering approach for fabricating aza-crown ether functionalized sodium alginate aerogels (ACSA) capable of highly selective Cu 2+ capture. The aerogels were synthesized via saccharide-ring oxidation, Cu 2+ -templated self-assembly, and reductive amination, enabling the covalent integration of aza-crown ether motifs within a hierarchically porous biopolymer matrix. Structural analyses (FTIR, 13 C NMR, XPS, SEM, TGA) confirmed the in situ formation of macrocyclic N/O coordination sites. Owing to their interconnected porosity and chemically stable framework, ACSA exhibited rapid sorption kinetics following a pseudo-second-order model (R 2 = 0.999) and a Langmuir maximum adsorption capacity of 150.82 mg·g −1 . The material displayed remarkable Cu 2+ selectivity over Zn 2+ , Cd 2+ , and Ni 2+ , arising from the precise alignment between Cu 2+ ionic radius (0.73 Å) and crown-cavity dimensions, synergistic N/O chelation, and Jahn-Teller stabilization. Over four regeneration cycles, ACSA retained more than 80% of its original adsorption capacity, confirming excellent durability and reusability. This saccharide-ring modification strategy eliminates crown-ether leaching and weak anchoring, offering a scalable and environmentally benign route to bio-based adsorbents that combine molecular recognition with structural stability for efficient Cu 2+ remediation and beyond.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Materials Chemistry B
·
2022
·Vol. 10
·期 10
·1650-1662
·
IF 7.571
Youliang Tian,Dalong Yin,Quan Cheng,Huiping Dang,Changchang Teng,Lifeng Yan
Achieving J-aggregation of a molecule is a fascinating way to construct fluorescent imaging and photothermal therapy agents in the second near-infrared window. Modulation of the balance between intermolecular π–π stacking and steric interactions is an elegant method to acquire J-aggregation dyes. Herein, we succeeded in synthesizing an aza-BODIPY dye with J-aggregation characteristics by introducing steric hindrance (TPA) and a π-bridge (thiophene) in the aza-BODIPY skeleton. In aqueous solutions, supramolecular J-aggregates with a regular lamellar stacking structure could quickly be formed by the dye-templated self-assembly and longer absorption (λmax = 939 nm) and emission (λmax = 1039 nm) bands were observed. After co-assembly of the dye and an amphiphilic polypeptide (POEGMA23–PAsp20), the obtained J-aggregation nanoparticles (J-NPs) with good water solubility and smaller size were more suitable for application in living organisms. In addition, the J-NPs exhibited good stability, considerable photothermal conversion capacity (η = 35.6%), and excellent resistance to pH, H2O2, and photobleaching. In vitro and in vivo experiments revealed that the J-NPs show great NIR-II fluorescence imaging capabilities and anti-tumor effects under 915 nm irradiation (1 W cm−2). This is a rare example of using BODIPY dyes to perform NIR-II fluorescence imaging-guided photothermal therapy under NIR-II irradiation.
研究领域:
化学
·
材料科学
·
生物医学工程
·
纳米技术
✓ 已验证
DOI
PubMed
高影响因子
Nanomaterials
·
2022
·Vol. 12
·期 20
·3636
·
IF 5.719
Jianchao Gong,Tingting Wang,Wei Zhang,Lin Han,Mingxiao Gao,Tianen Chen,Tao Shen,Yaxiong Ji
To explore the effect of spacer structure on the adsorption capability of organo-vermiculites (organo-Vts), a series of aza-containing gemini surfactants (5N, 7N and 8N) are applied to modify Na-vermiculite (Na-Vt). Large interlayer spacing, strong binding strength and high modifier availability are observed in organo-Vts, which endow them with superiority for the adsorption of 2-naphthol (2-NP) and bromophenol blue (BPB). The maximum adsorption capacities of 5N-Vt, 7N-Vt and 8N-Vt toward 2-NP/BPB are 142.08/364.49, 156.61/372.65 and 146.50/287.90 mg/g, respectively, with the adsorption processes well fit by the PSO model and Freundlich isotherm. The quicker adsorption equilibrium of 2-NP than BPB is due to the easier diffusion of smaller 2-NP molecules into the interlayer space of organo-Vts. Moreover, stable regeneration of 7N-Vt is verified, with feasibility in the binary-component system that is demonstrated. A combination of theoretical simulation and characterization is conducted to reveal the adsorption mechanism; the adsorption processes are mainly through partition processes, electrostatic interaction and functional interactions, in which the spacer structure affects the interlayer environment and adsorptive site distribution, whereas the adsorbate structure plays a role in the diffusion process and secondary intermolecular interactions. The results of this study demonstrate the versatile applicability of aza-based organo-Vts targeted at the removal of phenols and dyes as well as provide theoretical guidance for the structural optimization and mechanistic exploration of organo-Vt adsorbents.Keywords:organo-vermiculite;aza-containing gemini surfactant;2-Naphthol;bromophenol blue;adsorption
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
DIGESTIVE DISEASES AND SCIENCES
·
2022
·Vol. 67
·期 10
·4780-4796
·
IF 3.487
Duan Houyu,Ding Xiang,Luo Hesheng
Background and Aims KISS-1 is an established tumor suppressor that inhibits metastases in various malignancies. However, little is known regarding its role in esophageal squamous cell carcinoma (ESCC). The aim of the present study was to identify the possible mechanisms of KISS-1 in ESCC metastasis. Methods The expression levels of KISS-1 mRNA and protein in ESCC samples and cell lines were analyzed by qRT-PCR, IHC, and western blotting. Bisulfite sequencing PCR (BSP) and methylation-specific PCR (MSP) were used to analyze the methylation pattern of KISS-1 promoter in ESCC cells with or without 5-Aza-dC treatment. The role of KISS-1 in the progression and metastasis of ESCC was analyzed through in vitro functional assays. Results KISS-1 mRNA and protein were markedly downregulated in ESCC tissues and cell lines compared to the respective controls. Hypermethylation of KISS-1 promoter correlated to its lower expression levels in ESCC, and KISS-1 demethylation inhibited tumor progression. Ectopic KISS-1 overexpression inhibited tumor cell metastasis in vitro. In addition, KISS-1 overexpression downregulated the matrix metalloproteinase 2 and 9 (MMP2 and 9) and inhibited epithelial–mesenchymal transition (EMT). Finally, KISS-1 downregulated phosphorylated extracellular regulated protein kinase 1/2 (ERK1/2) and phosphorylated p38 mitogen-activated protein kinase (MAPK) without affecting their total expression levels in the ESCC cells. MAPK/ERK and p38 MAPK agonists reversed the suppressive effects of KISS-1. Conclusions The hypermethylation of KISS-1 promoter partly contributed to its downregulation in ESCC. KISS-1 inhibits the metastasis of ESCC cells by targeting the MMP2/9/ERK/p38 MAPK axis.
研究领域:
肿瘤学
·
分子生物学
·
癌症遗传学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MACROMOLECULES
·
2023
·
IF 5.5
Jirong Wang,Chi Zhang,Yong Zhang,Gong Chen,Rinaldo Poli,Xiaolin Xie,Zhigang Xue
Assembling polymer electrolytes (PEs) with lithium metal anodes is a promising strategy to address safety and specific capacity concerns. Molecular design on conductive polymer matrices avoids inherent high crystallinity, poor ion transport, and combustion drawbacks by adjusting the chain structure and functional groups. However, conventional structural modulation methods are difficult to conduct via in situ polymerization and cell assembly, thus hampering the further performance enhancement of PEs in lithium batteries. Herein, we report a simple aza-Michael addition method induced by lithium salts for designing and fabricating high-performance PEs. This method fulfills the in situ structure modulation of polyether-based PEs without any introduction of non-electrolytic components. The obtained polyether electrolytes exhibit a more amorphous cross-linked structure, leading to a favorable medium for ion migration and excellent flexibility. In addition, the introduction of C–N bonds imparts excellent non-flammability to the material as well as the ability to interact with sulfolane. Hence, the in situ-constructed gel polymer electrolyte (GPE) is characterized by a high ionic conductivity (1.76 × 10–4 S cm–1 at 30 °C) and excellent interface stability with the electrodes. The assembled Li/LiFePO4 (LFP) battery based on this newly designed GPE exhibits a high initial specific discharge capacity and a good rate performance (112.7 mAh g–1 at 5 C). Long-term stability was also demonstrated, with a capacity retention of 86.8% after 500 cycles at 0.5 C.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）