INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2018
·
IF 3.909
Ying Wang,Feng Bai,Qiang Luo,Mingliang Wu,Gang Song,Hongmei Zhang,Jian Cao,Yanqing Wang
Lycium barbarum polysaccharide-doxorubicin (LBP-DOX) nanoparticles were synthesized via a one-step Schiff base reaction between oxidized Lycium barbarum polysaccharide (oxidized LBP) and doxorubicin (DOX). The structure of LBP-DOX nanoparticles was characterized by multi-spectral methods, 1 H nuclear magnetic resonance ( 1 H NMR), transmission electron microscopy (TEM), and thermo gravimetric analysis (TGA). The rheological properties of LBP-DOX nanoparticles were studied. With the increase of shear rate, the viscosity of LBP and LBP-DOX nanoparticles gradually decreases at 25 °C. Under the same strain, the storage modulus (G′) and loss modulus (G″) of LBP-DOX nanoparticles were inferior to LBP. The DOX release from LBP-DOX nanoparticles was pH-dependent and was accelerated by decreasing pH. Cytotoxicity study showed that the LBP-DOX nanoparticles have significantly enhanced cytotoxicity in vitro, especially for human Hepatic cancer cell line HepG2.
研究领域:
药学
·
肿瘤学
·
生物材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2017
·
IF 5.401
Yu Cheng,Kai Ren,Dian Yang,Jie Wei
In this study, we propose a fluorescent bilayer hydrogel soft actuator that responds quickly to multiple environmental stimuli. The two layers of hydrogel contain poly(N-isopropylacrylamide) and poly(2-(dimethylamino) ethyl methacrylate), respectively, which enable their mechanical response to temperature and pH. Additionally, both hydrogel layers contain poly(ethylene oxide) diacrylate, which serves as the crosslinker. Thanks to the anisotropic swelling of two layers, the bilayer hydrogel structure exhibits rapid, reversible, and repeatable bending motion, under varying temperature or pH. In addition, a photo-sensitive coumarin-based unit is introduced into the hydrogel network to add fluorescence. A four-arm gripper made of hydrogel bilayers demonstrates rapid actuation in response to both temperature and pH. Furthermore, we design a circuit switch using the hydrogel bilayer to serve as one “bidirectional alarm” and selectively turn on light emitting diodes in different media. This work demonstrates the applications of the hydrogel bilayer as a soft actuator and a circuit switch in ionic circuitry, enabling potential applications in a wide range of fields, including biomimetic devices, biocompatible/medical devices, and environmental sensors.
研究领域:
材料科学
·
生物医学工程
·
智能材料
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2024
·
IF 7.4
Haofu Liu,Zhiqing Huang,Yingyu Shi,Tingyao Cai,Qi Miao,Zideng Gao,Zhenling Cui
Ensuring efficient iron absorption by crops is crucial in terms of high crop yields and food security . Bio-based materials effectively transport nutrients with minimal environmental impacts. Here, highly efficient lightweight iron fertilizers , CSG@Fe was prepared using chitosan hydrogels (CSG) as the adsorption carrier. Iron release from the various CSG@Fe preparations was slow under neutral conditions but rapid under acidic conditions. The effects of various cross-linking agents were investigated; 1.0 wt% genipin chitosan hydrogels iron fertilizer (GE-CSG@Fe) evidenced an excellent iron adsorption rate and a higher iron loading (326.15 mg/g) than the other two iron fertilizers. Iron release from CSG@Fe materials followed the Korsmeyer-Peppas model. Notably, wheat seed germination and tomato pot experiments revealed that GE-CSG@Fe significantly enhanced germination and growth. GE-CSG@Fe appropriately reduced the soil pH, protected ferrous ions from soil oxidation and rapid fixation, activated the soil microenvironment, and improved nutrient absorption by the roots of crops growing. This work provides a simple and effective strategy for overcoming constraints in the development and application of iron fertilizers and provides insights into the development of green and efficient iron fertilizers with intelligent response properties.
研究领域:
农业科学
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材料科学
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植物营养学
✓ 已验证
产品关联
DOI
高影响因子
EUROPEAN POLYMER JOURNAL
·
2013
·
IF 2.562
Jingquan Liu,Liang Cui,Na Kong,Colin J. Barrow,Wenrong Yang
A pH-sensitive, mechanically strong and thermally stable graphene/poly (acrylic acid) (graphene/PAA) hydrogel was prepared via reversible addition fragmentation transfer (RAFT) polymerizations in the presence of a cross-linking agent. The RAFT agent was covalently coupled onto graphene basal planes via an esterification reaction, with benzoic acid functionalities pre-attached on graphene with its aryl diazonium salt precursor. AFM and SEM analysis revealed the successful preparation of single layered graphene sheets and graphene/polymer hydrogels with pH controlled porous structures. Attenuated total reflection infrared (ATR-IR) and thermogravimetric analyzer (TGA) verified the successful stepwise preparation of graphene/PAA hydrogel. This graphene/PAA hydrogel was pH-sensitive and more mechanically elastic than the PAA hydrogel prepared without graphene. The pH sensitivity of the hydrogel was further utilized for controlled drug release. Doxorubicin was chosen as a model drug and loaded into the hydrogels. The drug loading and release experiment indicated that this hydrogel can be used to efficiently control drug release in the intestine environment (pH = 7.4), better than release in a more acidic environment.
研究领域:
材料科学
·
高分子化学
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纳米技术
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生物医学工程
·
药物递送
✓ 已验证
DOI
高影响因子
ANALYST
·
2018
·Vol. 143
·期 20
·5054-5060
·
IF 3.864
Bo Lin,Li Fan,Jinyin Ge,Wenjia Zhang,Caihong Zhang,Chuan Dong,Shaomin Shuang
A mitochondrial-targeted pH fluorescent probe 4-(2-(6-hydroxynaphthalen-2-yl)vinyl)-1-methylpyridin-1-ium was facilely synthesized via the carbon–carbon double bond bridging of 6-hydroxy-2-naphthaldehyde and 1,4-dimethylpyridinium iodide salt. The probe exhibited remarkable pH-dependent behavior in the linear range of 7.60–10.00, with a pKa value of 8.85 ± 0.04 near mitochondrial pH. A significantly large Stokes shift of 196 nm was obtained, which reduces the interference of excitation light. Application of the probe in live HepG2 cells indicated that the probe had excellent mitochondrial targeting ability and was successfully used to visualize mitochondrial pH fluctuations in live cells.
研究领域:
化学
·
生物化学
·
细胞生物学
·
荧光成像
✓ 已验证
DOI
PubMed
高影响因子
Journal of Materials Chemistry A
·
2025
·
IF 9.5
Yurou Chen,Yili Wei,Wenjun Song,Yiwen Zhang,Wenjie Tan,Jun Li,Shun Wang,Yadong Wu,Huile Jin
Phenolphthalein (PHT) is always applied as an acid-base indicator but suffers from too wide a range of characterization and uneven dispersion in thin films. To solve this problem, in this work, a composite filler SiO₂@PHT-1 with a jujube cake structure was designed. The size of phenolphthalein particles was effectively regulated by intervening in the growth process of phenolphthalein nuclei through silica (SiO₂). This also improved the dispersion of PHT in fluororubber (FKM) films, as well as the indicator film's tensile strength (57.1%) and initial decomposition temperature (201.6 °C), resulting in the pH indicator film with excellent tensile properties and thermal stability. The FKM/SiO₂@PHT-1 film is also capable of determining the pH value of a solution based on color and phenomena. In addition, the dense protective layer formed by the silica retards the release of PHT in the sample solution, which contributes to the reusability of the film. This method shows great promise and can be applied to laboratory and swimming pool alkalinity testing.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Scientific Reports
·
2017
·Vol. 7
·期 1
·1-9
·
IF 4.259
Liu Qingju,Chen Li,Zhang Zhikun,Du Bibai,Xiao Yating,Yang Kunhao,Gong Lingling,Wu Li,Li Xiangjun,He Yujian
D-amino acid oxidases (DAAO) are stereospecific enzymes which are generally almost inactive towards L-enantiomer in neutral solution when L-, D-amino acids are supplied as substrates. In this paper, the D-amino acid oxidase can catalytic oxidize L-amino acids by modulating pH of aqueous solution. With L-Pro as substrate, the catalytic rate ( k
cat ) and the affinity ( K
m ) of DAAO were 6.71 s −1 and 33 mM at pH 8.0, respectively, suggesting that optimal pH condition enhanced the activity of DAAO towards L-Pro. Similar results were obtained when L-Ala (pH 9.8), L-Arg (pH 6.5), L-Phe (pH 9.0), L-Thr (pH 9.4), and L-Val (pH 8.5) were catalyzed by DAAO at various pH values. The racemization of the L-amino acids was not found by capillary electrophoresis analysis during oxidation, and quantification analysis of L-amino acids before and after catalytic reaction was performed, which confirmed that the modulation of enantioselectivity of DAAO resulted from the oxidation of L-amino acids rather than D-amino acids by changing pH. A mechanistic model was proposed to explain enhanced activity of DAAO towards L-amino acids under optimal pH condition.
研究领域:
生物化学
·
酶学
✓ 已验证
DOI
PubMed
高影响因子
BIOPROCESS AND BIOSYSTEMS ENGINEERING
·
2024
·
IF 3.5
Wang Lingqin,Jia Mengya,Gao Dandan,Li Haixing
The probiotic fermentation of the bioactive substance gamma-aminobutyric acid (GABA) is an attractive research topic. There is still room for further improvement in reported GABA fermentation methods based on a single substrate ( l -glutamic acid or l -monosodium glutamate). Here, we devised a pH auto-buffering strategy to facilitate the fermentation of GABA by Levilactobacillus brevis CD0817. This strategy features a mixture of neutral monosodium l -glutamate plus acidic l -glutamic acid as the substrate. This mixture provides a mild initial pH; moreover, the newly dissolved l -glutamic acid automatically offsets the pH increase caused by substrate decarboxylation, maintaining the acidity essential for GABA fermentation. In this study, a flask trial was first performed to optimize the GABA fermentation parameters of Levilactobacillus brevis CD0817. The optimized parameters were further validated in a 10 L fermenter. The flask trial results revealed that the appropriate fermentation medium was composed of powdery l -glutamic acid (750 g/L), monosodium l -glutamate (34 g/L [0.2 mol/L]), glucose (5 g/L), yeast extract (35 g/L), MnSO 4 ·H 2 O (50 mg/L [0.3 mmol/L]), and Tween 80 (1.0 g/L). The appropriate fermentation temperature was 30 °C. The fermenter trial results revealed that GABA was slowly synthesized from 0–4 h, rapidly synthesized until 32 h, and finally reached 353.1 ± 8.3 g/L at 48 h, with the pH increasing from the initial value of 4.56 to the ultimate value of 6.10. The proposed pH auto-buffering strategy may be popular for other GABA fermentations.
研究领域:
生物技术
·
微生物学
·
发酵技术
·
生物化工
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Science Advances
·
2016
·Vol. 2
·期 8
·
IF 0
Bo Wu,Xiaowen Wang,Jun Yang,Zan Hua,Kangzhen Tian,Ran Kou,Jian Zhang,Shuji Ye,Yi Luo,Vincent S. J. Craig,Guangzhao Zhang,Guangming Liu
Weak polyelectrolytes have found extensive practical applications owing to their rich pH-responsive properties. In contrast, strong polyelectrolytes have long been regarded as pH-insensitive based on the well-established fact that the average degree of charging of strong polyelectrolyte chains is independent of pH. The possible applications of strong polyelectrolytes in smart materials have, thus, been severely limited. However, we demonstrate that almost all important properties of strong polyelectrolyte brushes (SPBs), such as chain conformation, hydration, stiffness, surface wettability, lubricity, adhesion, and protein adsorption are sensitive to pH. The pH response originates from the reorganization of the interchain hydrogen bond network between the grafted chains, triggered by the pH-mediated adsorption-desorption equilibrium of hydronium or hydroxide with the brushes. The reorganization process is firmly identified by advanced sum-frequency generation vibrational spectroscopy. Our findings not only provide a new understanding of the fundamental properties of SPBs but also uncover an extensive family of building blocks for constructing pH-responsive materials.
研究领域:
材料科学
·
物理化学
✓ 已验证
产品关联
DOI
PubMed
RSC Advances
·
2016
·Vol. 6
·期 37
·31374-31385
·
IF 3.289
Hongshan Liang,Yaqiong Pei,Jing Li,Wenfei Xiong,Yun He,Shilin Liu,Yan Li,Bin Li
Hydrogen-bonded polyphenol-based assemblies have attracted increasing interest for biomedical applications. Polyphenolic drug-loaded films can be coated on various devices with different shapes and sizes. Here, we report a novel versatile pH-responsive system based on hydrogen-bonded poly(ethylene glycol) (PEG)/tannin acid (TA) coatings on zein/TA colloidal nanoparticles (zein/TA/PEG NPs). Hydrogen bonding was considered to be the driving force for the coating buildup between PEG and TA, which was confirmed by Fourier transform infrared (FTIR) spectra. Because of the reversible/dynamic nature of hydrogen bonding, the release profile of TA was directed by pH value, temperature, ionic strength and TA concentration. The release rate of TA increased with increasing pH and temperature, but decreased with increasing ionic strength. This new drug delivery vehicle could also be used to load hydrophobic and unstable molecules through interacting with zein by hydrophobic interaction to achieve efficient protection. We demonstrated that the hydrophobic molecular nutrient, VD3, can be successfully loaded into zein/TA/PEG NPs with high encapsulation efficiency. Photostability against UV light was significantly improved after encapsulation. The encapsulated VD3 could be regulated not only by the pH of the solutions but also by TA concentration.
研究领域:
生物医学工程
·
药剂学
✓ 已验证
产品关联
DOI
高影响因子
Biomaterials Science
·
2017
·Vol. 5
·期 10
·2169-2178
·
IF 4.21
Shengcai Yang,Zhaohui Tang,Dawei Zhang,Mingxiao Deng,Xuesi Chen
A pH and redox dual-sensitive biodegradable polysaccharide, succinic acid-decorated dextran-g-phenylalanine ethyl ester-g-cysteine ethyl ester (Dex-SA-L-Phe-L-Cys), was synthesized to load doxorubicin hydrochloride (DOX·HCl). The DOX-loaded nanoparticles, which were prepared in aqueous solution and free of organic solvent, could spontaneously self-assemble into uniform sizes. When loading DOX·HCl, mercapto Dex-SA-L-Phe-L-Cys was oxidized into a crosslinked disulfide linkage to form pH and redox dual-sensitive nanoparticles (DOX-S-NPs). The amphiphilic polymer loaded DOX·HCl into the core through electrostatic and hydrophobic interactions, meanwhile the crosslinked disulfide bond could stabilize the drug loaded nanoparticles. As a control with similar polymer structure, succinic acid decorated dextran-g-phenylalanine ethyl ester (Dex-SA-L-Phe) was prepared to obtain pH-sensitive DOX-loaded micelles (DOX-N-NPs). The controlled pH and redox-dependent release profiles of the DOX-S-NPs in vitro were certified in different releasing mediums. Furthermore, the cellular uptake of the DOX-S-NPs was comparable with that of free DOX·HCl, determined by confocal laser scanning microscopy (CLSM) and flow cytometry. Cytotoxicity assay in vitro showed that the DOX-S-NPs and free DOX·HCl were similar in inhibiting the proliferation of non-small cell lung carcinoma A549 and breast cancer MCF-7 cell lines. DOX-S-NPs displayed similar antitumor efficiency compared with free DOX·HCl, but lower toxicity by body weight. These dual-sensitive DOX-S-NPs provide a useful strategy for anti-tumor therapy.
研究领域:
药剂学
·
生物医学工程
·
肿瘤学
✓ 已验证
DOI
PubMed
高影响因子
MEASUREMENT SCIENCE and TECHNOLOGY
·
2016
·Vol. 27
·期 10
·105101
·
IF 1.492
Jianxin Zhang,Yixuan Guo,Shangjin Li,Hui Xu
The solid-state pH electrode has the potential possibility to be used in many extreme situations with satisfactory accuracy and low cost. But its performance is affected by the solid electrolyte, preparation process, and the structure of the sensitive membrane, etc. In this work, the relationships between these factors and the characteristic of the prepared electrode were verified by controlling the preparation conditions with a variety of electrochemical methods. Firstly, the solid electrolyte poly(3,4-ethylenedioxythiophene)/poly(styrenesulfonate) (PEDOT/PSS) was electrochemically deposited on the screen-printed carbon electrode (SPCE) substrate by a potentiostatic method in an aqueous solution containing 0.01 M 3,4-ethylenedioxythiophene (EDOT) and 0.1 M polystyrene sulfonic (PSS) acid as the supporting electrolyte. The PEDOT films were then characterized by cyclic voltammetry (CV) in the 0.1 M NaNO3 aqueous solution in order to obtain the optimized polymerization potential and charges where the PEDOT film would have a higher redox capacitance. Finally, the pH electrode was prepared by coating the SPCE/PEDOT(PSS) with a plasticized polyvinyl chloride (PVC) membrane containing tridodecylamine as hydrogen ionophore manually, and experiments were carried out to study the effect of the usage of PVC per square millimeter on the response time and stability of the electrode to optimize the PVC film thickness. The potentiometric response of the pH electrode was studied in the buffer solutions with pH ranging from 5.00 to 10.81 by the open-circuit potential (OCP) method. Experimental results show that the sensitivity of the electrode is −55.7 ± 0.5 mV pH−1 (r2 > 0.9980) at room temperature (24 ± 1 °C) with pH ranging from 2.00–10.50, approximating to the theoretical nernstian slope (−59.16 mV pH−1),and the response time was less than 10 s. Moreover, it has low impedance, high accuracy and potential stability as well as some other useful properties such as pressure and heat resistance, hydrofluoric acid resistance, and it is not as fragile as the glass electrode.
研究领域:
分析化学
·
电化学
·
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）