Polymer Chemistry
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2014
·Vol. 5
·期 14
·4348-4357
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IF 5.368
Qiangfang He,Jianbing Huang,Hui Liang,Jiang Lu
A well-defined block copolymer polystyrene-block-poly(2-hydroxy-5-vinylbenzaldehyde) (PS-b-PHVB) was synthesized by reversible addition–fragmentation chain transfer (RAFT) polymerization of HVB using a trithiocarbonate terminated polystyrene macro-chain transfer agent. Sequential grafting of monoamine-terminated PEG (PEG–NH2) and 2-(2-aminoethoxy)ethanol (AME) onto the HVB blocks of PS-b-PHVB via aldehyde–amine condensation afforded an amphiphilic block copolymer PS-b-(PHVB-g-PEG-and-AME) bearing a pendant salicylidene Schiff base with a precise structure. PS-b-(PHVB-g-PEG-and-AME) could self-assemble in ethanol into micelles with salicylidene Schiff base groups at the core–shell interface. Addition of Zn2+ ions into the resulting micellar solution not only endowed the micelles with fluorescent features but also enabled the resulting luminescent micelles to be stabilized through ionic cross-linking in consequence of the salicylaldimine–Zn2+ complexation. The obtained fluorescent cross-linked micelle was “light-controllable” in terms of its fluorescence emission and cross-linking structure due to the reversibility of the salicylaldimine–Zn2+ coordinative bond in response to light stimuli. The reversible fluorescence decrease and recovery could be achieved periodically upon alternative 254 nm UV irradiation and maintaining in the dark, and the micelles could be de-stabilized by UV irradiation-induced de-cross-linking. The capture of guest molecules and the light-triggered release of the guests for this Zn2+ coordinated micelle were also demonstrated using the coumarin-153 dye as a model guest molecule.
研究领域:
高分子化学
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材料科学
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光化学
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DOI
高影响因子
Journal of Materials Chemistry B
·
2021
·Vol. 10
·期 14
·2617-2627
·
IF 6.331
Qisheng Ye,Rui Wang,Saitao Yan,Baoliang Chen,Xiaoying Zhu
Inspired by the stomatal feature of plant leaves, a photo-responsive membrane was developed to enhance the removal of irreversible membrane fouling and to control molecule release. Photo-responsive polymers were prepared by reacting the amine group of 4-amineazobenzene with about 3, 5 and 9 out of 12 carboxylic groups of PMAA which was grafted from P(VDF-CTFE) with a certain length. Subsequently, high-flux photo-responsive membranes (PRMs) were prepared from the heterogeneous polymers with different contents of photo-switchable azobenzene following a non-solvent-induced phase-inversion protocol. The pore size and surface hydrophilicity of PRMs could be reversibly increased by switching visible light to UV irradiation, which dramatically enhanced the backflushing efficiency on PRMs under UV irradiation. The “light-cleaning” process could recover more than 90% of the irreversible flux decline caused by typical organic foulant (BSA) and biological foulant (E. coli) on PRMs. The higher the content of azobenzene, the more obvious the pore size and hydrophilicity variation after light switching but the smaller the absolute pore size observed for PRMs. On the other hand, the light-switching gates of PRMs enabled the controlled release of molecules with different sizes. The novel PRM provided an efficient solution to mitigate irreversible membrane fouling and a light-triggered molecule release protocol, which would improve the membrane performance and further expand the application field of the membrane.
研究领域:
材料科学
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化学工程
·
环境科学
·
生物技术
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产品关联
DOI
PubMed
高影响因子
FOOD HYDROCOLLOIDS
·
2024
·
IF 11
Pu Zheng,Xinru Chen,Chunyang Zhao,Jialong Wang,Jianhong Zhang,Xiong Hu,Wenchao Geng,Qianqian Zhao
The Cyclodextrin (CD) encapsulation technology can significantly enhance the water solubility of Curcumin (CUR) and effectively protect it against chemical degradations. In the current study, a combination of experimental and multi-scale computational approaches was used to investigate the binding mechanism between CUR and β-CDs (β-CD, 2-HP-β-CD, Me-β-CD, and DM-β-CD). Phase solubility studies showed that β-CDs exhibited a strong binding affinity with CUR and significantly enhanced its solubility. SEM, PXRD, DSC, and TG analysis confirmed the formation of inclusion complexes, resulting in the transition of CUR from crystalline to an amorphous state. FTIR, 1 H, and 13 C NMR spectra deduced that CUR may have multiple binding conformations with β-CDs. The rationality of molecular dynamics simulation systems was confirmed by comparing the simulated IR spectrum from quantum mechanics with the experimental IR spectrum. MM-PBSA and umbrella sampling simulation calculated the binding free energy of the CUR/CD inclusion complexes, ranking Me-β-CD > DM-β-CD > 2-HP-β-CD > β-CD, and clarified that van der Waals interaction played a major role in stabilizing the inclusion complexes. RDF analysis confirmed that the release of high-energy water molecules drove the formation of the CUR/CD inclusion complex, and the β-CD substituents affected their exterior hydration layer. Additionally, principal component analysis (PCA) and non-covalent interaction analysis revealed three CUR/CD binding modes: bead-on-string, terminal insertion, and V-shaped-folding. The research strategy adopted here can serve as a paradigm for investigating the encapsulation mechanism of poorly soluble drugs with CDs.
研究领域:
药学
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物理化学
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计算化学
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材料科学
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产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2024
·
IF 4.9
Ting Lin,Lei Hu,Jie Chen,Qinghui Chen,Renhui Qiu,Jie Pang,Shuyi Wu
Photothermal therapy based on photothermal conversion has received increasing attention due to its non-invasiveness and low side effects. In this study, a 3D-printed biomass photothermal therapy device was prepared for accurate control of photothermal conversion and molecular release. The prepared black phosphorus nanosheets (BPNSs) showed excellent photothermal performance and antibacterial activity. A temperature-regulated sol-gel reversible system was prepared with konjac glucomannan (KGM), tara gum (TG), BPNSs, and manganese dioxide (MnO 2 ) nanoparticles. The sol-gel transition was attributed to the change of interactions of hydrogen bond, and molecular entanglement. Photothermal conversion films with accurate multi-layer and array structures were prepared by 3D printing using the biomass sol-gel conversion system. The photothermal conversion efficiency was regulated by the concentration of BPNSs and MnO 2 . Under infrared radiation (808 nm, 1 W/cm 2 ) for 5 min, the temperatures of hydrogel films with a MnO 2 concentration of 0, 0.5, and 1 % were raised from 25 to 29.3, 61.8, and 90.8 °C, respectively. The accurate temperature distribution induced the controlled release of small active molecules such as epigallocatechin gallate (EGCG) loaded in hydrogels, which was resulted from the changes in the hydrogel structure and the decrease in adsorption energy between polysaccharide and EGCG at high temperatures. This study provides a biomass 3D-printed multifunctional photothermal therapy device and more understanding of the molecular release during photothermal conversion.
研究领域:
生物医学工程
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材料科学
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纳米技术
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治疗学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）