POLYMER
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2023
·
IF 4.6
Xi Zhao,Guoxiang Wang,Yong Gao,Chong Cheng
Mixed shell polymer nanoparticles (MSPNs) have emerged as a very significant research topic in the field of macromolecular science. In this study, a robust method for efficient preparation of MSPNs with various morphologies via polymerization-induced self-assembly (PISA) of Y-shaped ABC miktoarm star copolymers was demonstrated. Poly( ε -caprolactone)- b -poly(methyl methacrylate) diblock copolymers carrying a trithiocarbonate (TTC) group at the diblock joint (PCL-TTC-PMMA) were synthesized via the sequential ring-opening polymerization of ε-caprolactone ( ε -CL) and atom transfer radical polymerization (ATRP) of methyl methacrylate (MMA) using a multifunctional initiator. Subsequently, PCL-TTC-PMMA copolymers acted as both macromolecular chain transfer agents (CTAs) and stabilizers to mediate reversible addition-fragmentation chain transfer (RAFT) dispersion polymerization of 4-vinylpyridene (4-VP) in toluene, producing MSPNs with different morphologies including spheres, short rods , worms and vesicles. The factors influencing the morphologies of MSPNs during PISA, including solid content and the chain length of stabilizers, were investigated. RAFT-based dispersion polymerizations of 4-VP monomers mediated by PCL-TTC-PMMA copolymers were also compared with those mediated by linear PMMA - TTC with approximately the same length of PCL-TTC-PMMA under the identical conditions. Their different PISA behaviors were unraveled.
研究领域:
大分子科学
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高分子化学
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纳米技术
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产品关联
DOI
高影响因子
ACS Applied Polymer Materials
·
2023
·
IF 5
Yan Qin,Weihua Su,Guihua Meng,Jianning Wu,Lin Cui,Shengchao Yang,Zhiyong Liu,Xuhong Guo
An intelligent responsive pesticide delivery system has been applied in agriculture to improve the utilization rate of pesticides. When plants are affected by fungi, a large number of reactive oxygen species (ROS) are produced rapidly on the wound surface. Based on this, a ROS responsive star polymer micellar slow-release system was constructed to load carbendazim (MBC) and improve its bioavailability. The star polymer was synthesized by using 3-mercaptopropionic acid, acetone, pentaerythritol (PER), ε-caprolactone (ε-CL), and methoxypolyethylene glycols (mPEG5000, Mw = 5000) and named PER-PCL-TK-mPEG5000. By loading MBC, the drug loading micelle MBC-loaded PER-PCL-TK-mPEG5000 was obtained. The cumulative release amount of MBC-loaded PER-PCL-TK-mPEG5000 containing H2O2 is 1.64 times of that without H2O2 after 120 h release. The inhibitory rate of MBC-loaded PER-PCL-TK-mPEG5000 containing H2O2 against Rhizoctonia solani (R. solani) was 91.6%. The critical micelle concentration (CMC) of PER-PCL-TK-mPEG5000 is 4.37 mg/L, and the result showed that PER-PCL-TK-mPEG5000 and MBC-loaded PER-PCL-TK-mPEG5000 have good stability at 4 °C for 14 d. This study proved that the strategy of designing pesticide vectors according to the target environment can be widely used to protect crops, improve pesticide utilization rate, and protect the environment.
研究领域:
农业科学
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材料科学
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植物保护
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产品关联
DOI
高影响因子
ACS Biomaterials Science & Engineering
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2015
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IF 0
Qiu Li,Yiguang Jin,Miao Li,Jun-Xing Dong
Tumor targeting and controlled drug release at the target are the key problems for cancer pharmacotherapy. A simply structured pH-responsive nanocarrier was prepared to achieve the above aims in this study. A four-armed star copolymer, tetra-(methoxy-poly(ethylene glycol)-poly(2-(N,N-diethylamino)ethyl methacrylate)-poly(ε-caprolactone) pentaerythritol ((mPEG-pDEA-PCL)4-PET, PDCP), was synthesized via the ring-opening polymerization, atom transfer radical polymerization and click chemistry, which formed a monomolecular nanocarrier in water. Its size and zeta potential were strongly pH-dependent from 71 nm and 2.1 mV at pH 8 to 127.5 nm and 25.4 mV at pH 5. The morphological change of pDEA chains was the basic reason. The chains were protonated at lower pH so as to freely extend to the aqueous media, though they were hydrophobic at higher pH to coat on the surface of hydrophobic cores. The star-shaped PDCP had a large hydrophobic core to load hydrophobic drugs (e.g., paclitaxel). High effective drug entrapment in the blood circulation and rapid drug release at the tumor tissues was achieved in PDCP due to its pH-responsive function. The MCF-7 cytotoxicity of the paclitaxel-loaded PDCP nanocarriers at pH 6.5 was similar to free paclitaxel. And the PDCP nanocarriers were well internalized by the MCF-7 cells according to the flow cytometry and laser confocal microscopy. The paclitaxel-loaded PDCP nanocarriers showed the comparable in vivo anticancer effect to the paclitaxel solution (Taxol) although the former’s toxicity was much lower than the latter. The star-shaped pH-responsive monomolecular PDCP nanocarriers are suitable to deliver hydrophobic anticancer drugs for cancer therapy with tumor targeting and controlled drug release.
研究领域:
药学
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生物医学工程
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肿瘤学
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产品关联
DOI
PubMed
PHYTOCHEMISTRY
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2018
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IF 3.186
Xuchao Jia,Haihui Xie,Yueming Jiang,Xiaoyi Wei
Thirteen flavonoids were isolated from the fresh sweet fruit of Averrhoa carambola L. (Oxalidaceae), commonly known as star fruit, and their structures were determined by spectroscopic and chemical methods. 8-Carboxymethyl-(+)-epicatechin methyl ester , pinobanksin 3- O -β- d -glucoside, and carambolasides M–Q were undescribed structures. (+)-Epicatechin, aromadendrin 3- O -β- d -glucoside, helicioside A, taxifolin 3′- O -β- d -glucoside, galangin 3- O -rutinoside, and isorhamnetin 3- O -rutinoside were reported from this species for the first time. Pinobanksin 3- O -β- d -glucoside and carambolasides M–Q showed more potent 2,2′-azinobis-(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) radical cation scavenging activity (IC 50 = 5.3–2.3 μM) than l -ascorbic acid (10.5 μM). Further, (+)-epicatechin, pinobanksin 3- O -β- d -glucoside, isorhamnetin 3- O -rutinoside, and carambolasides O–Q exhibited weak porcine pancreatic lipase inhibitory activity.
研究领域:
植物化学
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药理学
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产品关联
DOI
PubMed
高影响因子
COMPOSITES SCIENCE AND TECHNOLOGY
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2017
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IF 4.873
Ailian Wang,Hao Xu,Xu Liu,Shi Wang,Qian Zhou,Jie Chen,Liaoyun Zhang
Here, two type of composite star polymer electrolytes enhanced by carbon nano-tube (CNT) or fullerene (C 60 ) prepared through a solution-casting technique are investigated. The as-prepared free-standing carbon nano-composite polymer electrolyte membranes exhibit excellent comprehensive performances including high thermal stability (initial thermal degradation temperatures about 383 °C) and good electrochemical properties . However, different carbon nanomaterials bring different influence on electrochemical performances of composite polymer electrolytes. The ionic conductivity of carbon nanotube composite polymer electrolyte (HBPS-(PMMA- b -PPEGMA) 30 /CNT/LiTFSI) is higher than that of fullerene composite polymer electrolyte. The highest ionic conductivity of HBPS-(PMMA- b -PPEGMA) 30 /CNT/LiTFSI electrolyte can reach 1.06 × 10 −5 S cm −1 at 30 °C and lithium-ion transference number reaches 0.52. In addition, two types of carbon nano-composite star polymer electrolytes both exhibit wide electrochemical window with oxidation potential above 5.2 V, good interfacial stability and interfacial compatibility. Moreover, assembled Li/LiFePO 4 cells based on HBPS-(PMMA- b -PPEGMA) 30 /CNT/LiTFSI electrolytes possess good specific capacity with the highest value of 133 mAhh g −1 , while the cells based on HBPS-(PMMA- b -PPEGMA) 30 /C 60 /LiTFSI electrolytes show a great cycle stability.
研究领域:
材料科学
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电化学
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产品关联
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
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2024
·Vol. 48
·期 48
·20332-20342
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IF 2.7
Guanghao Mao,Huaxin Yang,Shuhang Deng,Wenyu Cao,Ping Deng,Yan Yu
A pair of star-like conjugated isomers (Tetra-8-IQ and Tetra-9-IQ) with indolo[2,3-b]quinoxaline as the star arm and tetraphenylethylene as the star core have been designed and synthesized. A comparative study has been conducted on the structural characteristics, electronic energy levels, spectral absorption, aggregation-induced emission, acid-stimulus response, and fluorescent applications of the two isomers. The results show that Tetra-8-IQ has lower lowest unoccupied molecular orbital/highest occupied molecular orbital energy levels, more redshifted optical absorption, and stronger fluorescence emission than Tetra-9-IQ. The two isomers are novel organic fluorescent materials as they both possess aggregation-induced emission characteristics and reversible acidichromism features. Tetra-8-IQ and Tetra-9-IQ were successfully applied in filter paper test strips and PMMA-based blending film to achieve fluorescent switch signals. Based on these findings, the INHIBIT and IMPLICATION molecular logic gates were successfully established, where acid and base were adopted as the input stimuli.
研究领域:
有机化学
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材料科学
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光化学
✓ 已验证
DOI
高影响因子
MOLECULES
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2025
·Vol. 30
·期 4
·787
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IF 4.6
Shuaihua Liu,Tian Yao,Donghui Xia,Quan Liu,Guanghui Tian,Yang Liu
Low-molecular-mass gelators (LMMGs) as stabilizers for gel emulsions offer numerous advantages, such as low usage, functionalizability, and insensitivity to phase ratio. Using LMMGs as stabilizers is one of the effective strategies for preparing gel emulsions. Currently, developing LMMGs and stable gel emulsion systems in a rapid and convenient manner remains a challenge. To cope with the challenge, this study aims to develop a simple and efficient gel emulsion preparation method based on LMMGs. In this study, a cholesterol-based star-shaped derivative (CSD) was designed and synthesized as an LMMG. Based on gelation experiments, a high internal phase W/O gel emulsion system (H2O/CSD-poly(oligo)-dimethylsiloxane/dichloromethane) was successfully developed and stabilized synergistically by the stabilizer (CSD) and the crosslinker (poly(oligo)-dimethylsiloxane with two olefinic bonds at its ends, D-PDMS). The results demonstrate that the synergistic interaction between CSD and D-PDMS is critical for the formation of the gel emulsion. Building on the original gel emulsion system, two novel in situ polymerizable gel emulsion systems (H2O/CSD-D-PDMS/dichloromethane-tert-butyl methacrylate and H2O/CSD-D-PDMS/dichloromethane-N-tert-butyl methacrylamide) were successfully developed by introducing suitable amphiphilic (hydrophilic/lipophilic) polymerizable monomers. This study found that changes in the amphiphilicity of the introduced monomers significantly affected the stability and microscopic morphology of the gel emulsion system. The findings indicate that constructing a hydrophilic/lipophilic balanced system via the synergistic action of stabilizers and crosslinkers in a solvent system, followed by the introduction of polymerizable monomers, is a simple and efficient method for rapidly developing novel polymerizable gel emulsions. These new polymerizable gel emulsions lay the foundation for the subsequent preparation of porous organic polymers (POPs).
研究领域:
材料科学
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化学工程
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产品关联
DOI
PubMed
高影响因子
BIOMATERIALS
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2010
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IF 7.365
Xingyu Chen,Wei Wu,Zhizhang Guo,Jianyu Xin,Jianshu Li
A glucose-sensitive multilayer film was fabricated by the layer-by-layer (LbL) assembly method with positively charged 21-arm poly[2-(dimethylamino)ethyl methacrylate] (star PDMAEMA) and negatively charged insulin and glucose oxidase (GOD) in the form of {(Star PDMAEMA/Insulin) 4 + (Star PDMAEMA/GOD) 4 + Star PDMAEMA}. The multilayer film shows an on-off regulation of insulin release in response to stepwise glucose challenge in vitro . It is found that the unique structure of star PDMAEMA and interdiffusion of charged insulin are the main factors to control the on-off status of the film. Reversible surface morphology transitions of the multilayer film were also observed, revealing a phase separation and large-scale reorganization process. Furthermore, the multilayer film could continuously release enough insulin in vivo after being subcutaneously implanted in streptocozotin-induced diabetic rats and reduce the blood glucose level for at least two weeks. It is indicated that such system may have substantial potential as a glucose-sensitive carrier for insulin due to its distinct mechanism.
研究领域:
生物材料学
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医学工程
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药物递送系统
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DOI
高影响因子
JOURNAL OF NANOBIOTECHNOLOGY
·
2020
·Vol. 18
·期 1
·1-16
·
IF 6.518
Guo Fangyuan,Fu Qiafan,Zhou Kang,Jin Chenghao,Wu Wenchao,Ji Xugang,Yan Qinying,Yang Qingliang,Wu Danjun,Li Aiqin,Yang Gensheng
Background Specific targeting ability and good cell penetration are two critical requirements of tumor-targeted delivery systems. In the present work, we developed a novel matrix metalloprotein-triggered, cell-penetrating, peptide-modified, star-shaped nanoparticle (NP) based on a functionalized copolymer (MePEG-Peptide-Tri-CL), with the peptide composed of GPLGIAG (matrix metalloprotein-triggered peptide for targeted delivery) and r9 (cell-penetrating peptide for penetration improvement) to enhance its biological specificity and therapeutic effect.Results Based on the in vitro release study, a sustained release profile was achieved for curcumin (Cur) release from the Cur-P-NPs at pH 7.4. Furthermore, the release rate of Cur was accelerated in the enzymatic reaction. MTT assay results indicated that the biocompatibility of polymer NPs (P-NPs) was inversely related to the NP concentration, while the efficiency toward tumor cell inhibition was positively related to the Cur-P-NP concentration. In addition, Cur-P-NPs showed higher fluorescence intensity than Cur-NPs in tumor cells, indicating improved penetration of tumor cells. An in vivo biodistribution study further demonstrated that Cur-P-NPs exhibited stronger targeting to A549 xenografts than to normal tissue. Furthermore, the strongest tumor growth inhibition (76.95%) was observed in Cur-P-NP-treated A549 tumor xenograft nude mice, with slight pulmonary toxicity.Conclusion All results demonstrated that Cur-P-NP is a promising drug delivery system that possesses specific enzyme responsiveness for use in anti-tumor therapy.
研究领域:
药剂学
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肿瘤学
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生物材料
✓ 已验证
DOI
PubMed
高影响因子
Chemical Science
·
2025
·
IF 7.4
Zihao Guan,Lulu Fu,Lu Chen,Zhiyuan Wei,Fang Liu,Yang Zhao,Zhipeng Huang,Mark G Humphrey,Chi Zhang
The long-chain ligands and weak charge-transport capacity of perovskite nanocrystal (NC) always hinder its optoelectronic applications. Our study proposes an effective strategy to unlock the optimized nonlinear optical (NLO) properties of perovskite via the aromatic ligand-exchange plus porphyrin-axial-coordination. Synthesized porphyrin-pyridine dual-modified CsPbBr3-NC hybrid material, fabricated by 4-(aminomethyl)pyridine (PyMA) and a novel star-shaped zinc-porphyrin trisubstituted triazacoronene compound (ZnPr) modifications, exhibits excellent NLO absorption performance under femtosecond (fs) laser irradiation in the visible to near-infrared range. Specifically, its nonlinear absorption coefficient is 10 times higher than that of the pristine CsPbBr3-NC and it also possesses an outstanding optical limiting (OL) capability with an OL threshold as low as 1.8 mJ cm−2. The modification of PyMA ligands reduces the trap state density on the perovskite surface and promotes the electronic coupling between the NC lattices. With the aid of PyMA coordinating with the Zn atoms in ZnPr, large-size planar porphyrins are anchored on the perovskite surface from the axial position, which may enhance the ligand protection capability and thereby significantly facilitate the charge transport between porphyrin components and perovskite NCs. The above two-step modification synergistically contributes to the prominent NLO performance. Our work affords a new viable paradigm for developing multi-field and high-performance perovskite NC photonic materials and devices.
研究领域:
材料科学
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光学工程
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产品关联
DOI
PubMed
高影响因子
ANALYTICA CHIMICA ACTA
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2024
·
IF 5.7
Hui Bai,Lei Chen
Background As the derivatives of cyclodextrin (CD), cyclodextrin polymers (CDPs) effectively increase the concentration of CD units and construct supramolecular structures with unique stereoselectivity by the structure design. CDPs have shown significant potential in chiral separation, however, the process of stereoselective interactions on chiral stationary phases (CSPs) and the specific contribution of intermolecular forces are still a challenge issue. A comprehensive understanding of the chiral recognition mechanism of CDPs will help to optimize chiral separation conditions and design new CSPs. Results The star CDP with a supermolecular structure was synthesized by grafting β-CD onto the external 6-position hydroxyl groups using β-CD as the parent nucleus. The enhanced host-guest recognition ability of CD supramolecular polymer structure provided better inclusion interaction and increased chiral recognition of the isomers. The Star-CD CSP with star CDP as a chiral ligand performed satisfactory stereoisomer separation ability with the separation factor (α) up to 2.0 for various quinoline alkaloid isomers and 1.89 for catechins. To elucidate its chiral separation mechanism, molecular docking was used to construct the three-dimensional visual models of the binding sites and the contribution of non-covalent interactions between Star-CD CSP and quinoline alkaloid isomers. In addition, the formation sites of non-covalent interactions on the CD monomers of the polymer side chains were confirmed from the actual geometric structure by analyzing the NMR chemical shift changes before and after the formation of complexes between Star-CD polymers and isomers. Combined with the mutual evidence of molecular simulation and chiral NMR, the specific recognition mechanism of selector-selectand complexes was comprehensively expounded. Significance The multi-mode CSP based on cyclodextrin supramolecular structure provides new ideas for the stereoisomeric separation of complex chiral components with multiple chiral centers in natural products. Not limited to the macroscopic performance of the chromatographic separation, molecular docking explored the theoretical model of chiral recognition from the molecular level. The chiral NMR analysis confirmed the credibility of the model from the geometry structure, and then the recognition mechanism of multi-mode CSP was fully elaborated combining the above three aspects.
研究领域:
分析化学
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色谱学
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超分子化学
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分子识别
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产品关联
DOI
PubMed
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 99
·81482-81491
·
IF 3.84
Xuefei Leng,Zhiyong Wei,Yingying Ren,Yang Li,Yurong Wang,Qinyi Wang
In this work, two series of linear-comb and star-comb well defined graft poly(L-lactide) (PLLA) have been synthesized conveniently by one-pot ring-opening polymerization (ROP) of L-lactide using functionalized polybutadiene macroinitiators. The used organocatalyst of 1,8-diazabicyclo[5,4,0]undec-7-ene (DBU) allows the polymerization of L-lactide to proceed rapidly at room temperature. Kinetic studies of the ROP reaction in this system indicate first-order kinetics in monomer concentration. 1H NMR and GPC techniques are employed to characterize the synthesized polymers, validating the formation of the desired comb structures with controllable chain length. Linear-comb and star-comb graft PLLA were comparatively studied as well as with linear PLLA by DSC and POM. The results reveal that the comb structure gives a remarkable improvement of PLLA crystallization ability in both crystallinity and growth rate of spherulites. Furthermore, the more compacted star-comb structure imposes restriction on chain mobility, which weakens the growth effect to some extent. It is found that the glass transition temperature (Tg) and melting temperature (Tm) significantly depend on the side chain length and backbone structure. Rheological studies of both melt and instinct viscosity of the solution show that star-comb PLLA has the lowest hydrodynamic volume compared with linear-comb PLLA and linear PLLA.
研究领域:
高分子化学
·
材料科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）