MICROCHIMICA ACTA
·
2017
·Vol. 184
·期 4
·1185-1190
·
IF 4.58
Gong Lingling,Du Bibai,Pan Long,Liu Qingju,Yang Kunhao,Wang Wei,Zhao Hong,Wu Li,He Yujian
The authors describe a colorimetric assay for the determination of As(III) in aqueous solution using citrate capped gold nanoparticles (AuNPs) which, in the presence of As(III), undergo aggregation due to the interaction of citrate ion with As(III). This results in an easily detectable color change from wine-red to blue. The ratio of the absorbances at 661 and 519 nm is linearly related to the As(III) concentration in the 4 to 100 ppb range, with a detection limit as low as 1.8 ppb (at 3σ) which is below the guideline value of 10 ppb. The method is rather simple in that it does not require the surface of the AuNPs to be modified. It was successfully applied to the determination of As(III) in spiked drinking water where it gave adequate recoveries.
The ratio of the absorbances at 661 and 519 nm is linearly related to the As(III) concentration in the 4 to 100 ppb range, with a detection limit as low as 1.8 ppb (at 3σ) which is below the guideline value of 10 ppb.
研究领域:
分析化学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2017
·
IF 7.504
Meng-Yun Peng,Di-Wei Zheng,Shi-Bo Wang,Si-Xue Cheng,Xian-Zheng Zhang
A multifunctional nanosystem based on two-dimensional molybdenum disulfide (MoS2) was developed for synergistic tumor therapy. MoS2 was stabilized with lipoic acid (LA)-modified poly(ethylene glycol) and modified with a pH-responsive charge-convertible peptide (LA-K11(DMA)). Then, a positively charged photosensitizer, toluidine blue O (TBO), was loaded on MoS2 via physical absorption. The negatively charged LA-K11(DMA) peptide was converted into a positively charged one under acidic conditions. Charge conversion of the peptide could reduce the binding force between positively charged TBO and MoS2, leading to TBO release. Furthermore, the positively charged nanosystem was easily endocytosed by cells. Photo-induced hyperthermia of MoS2 in the tumor areas could promote TBO release and exhibited photothermal therapy. In vitro and in vivo results demonstrated that fluorescence and photo-induced reactive oxygen species (ROS) generation of TBO were severely decreased by MoS2 under normal conditions. While in the acidic condition, the pH-responsive nanosystem exhibited a highly specific and efficient antitumor effect with TBO release and photo-induced ROS generation, suggesting to be a promising accessory for synergistic tumor therapy.
研究领域:
纳米医学
·
癌症治疗
·
材料科学
·
生物材料
·
药学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Crystals
·
2020
·Vol. 10
·期 1
·39
·
IF 2.404
Xiaomin Guo,Bin Zheng,Jinlei Wang
Composite materials that contain metal-organic frameworks (MOFs) as a filler and a polymer matrix have attracted attention because they present a combination of high porosity and structural integrity. Phase compatibilities of the MOF and polymer play a vital role in the formation of the composites. In particular, the stiff polymer cannot easily adapt to penetrate into the surface pore of MOF and mainly depends on chemical attractions to form the MOF/polymer composites. We report the synthesis of MOF/polyethersulfone (Young’s modulus = ~2.6 GPa) via different fabrication methods, different MOF types and particle sizes, and different solvents. The formed network structures are robust, monolithic composites with 60% MOF loadings; also, the MOF surface area and porosity were fully preserved. The study explored the formation of the composite between MOF and a stiff polymer and encourages the design of more MOF/polymer composite materials across a wide range of applications.Keywords:metal-organic framework;composite materials;interface compatibility;phase inversion
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
INORGANIC CHEMISTRY
·
2020
·
IF 4.825
Li Zhong,Junyang Ding,Xian Wang,Lulu Chai,Ting-Ting Li,Kongzhao Su,Yue Hu,Jinjie Qian,Shaoming Huang
The rapid development of suitable and cheap water oxidation catalysts is of great significance in energy conversion and storage. In this context, herein we have synthesized two different types of metal–organic frameworks (MOFs, denoted as BMM-11 and BMM-12) constructed from the same metal salts (cobalt nitrate) and organic linkers (H4BPTC) at the similar solvothermal conditions. Interestingly, we learned that both crystalline materials can be conveniently converted into each other by a single-crystal-to-single-crystal transformation method at their corresponding synthetic conditions. Meanwhile, we applied them directly as electrocatalysts into OER application where the pure BMM-11 and BMM-12 can achieve a stable current density of 10 mA cm–2 with an overpotential of 0.362 and 0.393 V, respectively, during which MOF degradation unexpectedly occurs. After electrolysis, the following microscopic, spectroscopic, as well as electrochemical measurements confirm that these initial MOF precursors are rapidly transformed into the mixed phases of CoOxHy species consisting of CoOOH and Co(OH)2, which are essentially active components for OER performance. Finally, we have also considered other strategies to improve MOF-derived composites in oxygen evolution activity, including bimetallic doping and physical grinding strategy. The approach described here can further be extended to other cobalt-based MOFs-derived electrocatalysts for water splitting.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF CHROMATOGRAPHY A
·
2019
·
IF 3.858
Mingxian Li,Congcong Gu,Lan Luo,Jie Zhou,Jing Liu,Feng Zheng
The selective and sensitive determination of potential genotoxic methanesulfonate impurities in drug substances is highly challenging. A new method is reported for testing of methyl methanesulfonate (MMS), ethyl methanesulfonate (EMS) and isopropyl methanesulfonate (IPMS) in active pharmaceutical ingredients (APIs). Headspace single drop microextraction (HS-SDME) with room-temperature ionic liquid (RTIL) as extractant was employed to preconcentrate analytes and eliminate the drug matrix simultaneously. In order to increase volatilities for HS extraction and to improve their reactivity of the further derivatization at the same time, sodium iodide (NaI) was added to the sample to derivatize methanesulfonates to the corresponding iodoalkanes. The iodoalkanes in the extract were derivatized with N , N -diethyldithiocarbamate (DDTC) after HS-SDME, followed by separation and detection with high-performance liquid chromatography with ultraviolet detection (HPLC-UV). Several important parameters, including reaction temperature, reaction time and concentration of NaI, sample volume, microdrop volume, stirring rate, salt addition, extraction time, concentration, reaction time and reaction temperature of DDTC were investigated. Under the optimal conditions, LODs and LOQs of all methanesulfonates were 15 ng mL −1 and 40 ng mL −1 , respectively. Linearity (correlation coefficient values r > 0.999) and precision (the relative standard deviations were 1.0–4.6%) of six repeated injections were obtained. The recoveries at three spiked concentration levels were all in the range of 86.2–107.5% with the relative standard deviations <3.5%. The method reported here avoids interference of drug substances efficiently and detects methanesulfonate impurities in high sensitivity by HPLC-UV in Imatinib Mesylate and Levofloxacin Mesylate.
研究领域:
分析化学
·
药物分析
·
毒理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
International Journal of Polymer Science
·
2020
·
IF 1.646
Shuxi Gao,Xiaoyong Hu,Lei Zhang,Yuliang Mai,Hao Pang,Yongqiang Dai,Bing Liao
One silsesquioxane-polythiophene hybrid copolymer, with combined star-like structure and intramolecular heterogeneity, was synthesized and sufficiently characterized via various methods, including FTIR, NMR, and SEC measurements. According to the exploration and characterization results, it was much more efficient at modifying SWNTs than its linear analogs in aqueous solution. The hydrophobic silsesquioxane core and PEDOT chains could locally anchor to the surface of the nanotubes, while the soluble flexible copolymer chains extended into the solution and rigid conjugated chains provided some - stacking effect to enhance adhesive force with the conjugated structure of the carbon nanotube, imparting steric stabilization to nanotube dispersion. The noncovalent interaction with SWNTs and solubility in aqueous solution improved the electrochemical characteristics of the modified-SWNT composite and availed for the preparation of a flexible and transparent electroactive film. Accordingly, this kind of silsesquioxane-polythiophene hybrid copolymer will be forwarded to apply to the assembling of flexible optoelectronic devices.
研究领域:
材料科学
·
纳米技术
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
FOOD CONTROL
·
2020
·
IF 4.258
Xuefei Shao,Baocai Xu,Hui Zhou,Conggui Chen,Peijun Li
The mechanism of decreasing N- nitrosodimethylamine (NDMA) by Lactobacillus pentosus R3 isolated from Chinese dry sausage was assessed in a model system. The model system was devised using a DeMan-Rogosa and Sharp-ferrous sulfate broth supplement with NDMA or its precursors. The results showed that inoculating L. pentosus R3 could significantly decrease the content of NDMA ( P < 0.05). The NDMA precursors (dimethylamine and putrescine) were found to be decreased by L. pentosus R3 ( P < 0.05). Nitrite was degraded to nitrosonium cation by acidolysis, which may promote the formation of NDMA. Direct degradation of NDMA by L. pentosus R3 was also observed. The strain exhibited antioxidant activities , including Fe 2+ chelating activity, which may be responsible for inhibiting the formation reaction and decreasing the precursors of NDMA. Thus, L. pentosus R3 decreased the content of NDMA possibly by three ways: inhibition of the formation reaction, decrease in precursors (DMA and putrescine) and direct degradation. It is interesting to understand the mechanism of decreasing NDMA by L. pentosus R3 to improve the safety of fermented meat products .
研究领域:
食品科学
·
微生物学
✓ 已验证
产品关联
DOI
高影响因子
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
·
2019
·Vol. 21
·期 44
·24572-24583
·
IF 3.567
Jiying Liang,Wenting Wei,Huiqin Yao,Keren Shi,Hongyun Liu
In this work, poly(N,N′-dimethylaminoethylmethacrylate-co-N-isopropylacrylamide) copolymer films were polymerized on the surface of Au electrodes with a facile one-step method, and Au nanoclusters (AuNCs) and tetraphenylethene (TPE) were synchronously embedded in the films, designated as P(DMA-co-NIPA)/AuNCs/TPE. Ferrocene dicarboxylic acid (FDA), an electroactive probe in solution displayed inverse pH- and SO42−-sensitive on–off cyclic voltammetric (CV) behaviors at the film electrodes. The electrocatalytic oxidation of nicotinamide adenine dinucleotide (NADH) mediated by FDA in solution could substantially amplify the CV response difference between the on and off states. Moreover, the two fluorescence emission (FL) signals from the TPE constituent at 450 nm and AuNCs component at 660 nm in the films also demonstrated SO42−- and pH-sensitive behaviors. Based on the aforementioned results, a 4-input/9-output biomolecular logic circuit was constructed with pH, Na2SO4, FDA and NADH as the inputs, and the CV signals and the FL responses at 450 and 660 nm at different levels as the outputs. Additionally, some functional non-Boolean devices were elaborately designed on an identical platform, including a 1-to-2 decoder, a 2-to-1 encoder, a 1-to-2 demultiplexer and different types of keypad locks. This work combines copolymer films, bioelectrocatalysis, and fluorescence together so that more complicated biocomputing systems could be established. This work may pave a new way to develop advanced and sophisticated biocomputing logic circuits and functional devices in the future.
研究领域:
生物化学
·
纳米生物学
·
分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2024
·
IF 18.5
Xuan Liu,Hui Jie Zhang,Shuangshuang Xi,Yifan Zhang,Ping Rao,Xiangyu You,Shaoxing Qu
Hydrogel coatings are crucial strategies for integrating substrates with functional surfaces. Hydrogel coating with a facile coating process, high toughness, and ultrathin thickness is highly desired. This study utilizes the self-assembly of hydrophobic lignin into chain-dense regions during solvent evaporation and constructed a hydrogel coating with Janus structure from hydrophilic polymer and hydrophobic lignin through a facile coating-drying-swelling process at room temperature (25 °C). The Janus structure formed as the hydrophobic lignin-aggregated regions remained at the bottom while the hydrophilic polymer swell at the top. The lignin-aggregated regions constrained the swelling of the hydrogel coating, allowing for an ultrathin coating layer of ≈8 µm. Additionally, the lignin-aggregated region increases the stiffness and toughness of the thin hydrogel coating film by establishing strong interfacial bonding with the substrate via dense Van der Waals forces, thereby increasing overall adhesion energy with thin thickness and to various substrates such as glass, polytetrafluoroethylene (PTFE), metal, and rubber. The hydration layer is formed by the hydrophilic polymer swollen on top, which improves lubrication and antifouling properties. Furthermore, the hydrogel coating exhibits high stability in water and saline solutions, ultraviolet shielding properties, and the ability to be removed and recycled after use.
研究领域:
材料科学
·
表面工程
·
生物材料
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2019
·Vol. 136
·期 25
·47683
·
IF 2.188
Bin Guo,Huimin Wang,Danan Lan,Xiaomin Pang,Yiming Li,Haiyan Liu,Hongyuan Yan,Ligai Bai
Three temperature-sensitive monolithic columns were prepared by atom transfer radical polymerization and oxidation–reduction method using the initiator systems of CCl 4 /FeCl 2 , BPO/DMA, and APS/TEMED, respectively. The three monoliths were characterized by scanning electron microscopy, nitrogen adsorption, and thermogravimetric analysis. The obtained monolithic columns were used as on-line solid phase extraction sorbent coupled with high-performance liquid chromatography for the enrichment of β-sitosterol. By comparing some influencing factors on the adsorption, the optimum temperature-sensitive monolithic column which was initiated by CCl 4 /FeCl 2 was selected for enrichment of β-sitosterol from plant oil. The maximum adsorption capacity of the monolith for β-sitosterol was 10.0031 mg/g. The limit of detection and limit of quantitation were 0.039 and 0.13 mg/mL, respectively. The recovery was in the range of 90.21–98.26%. The results showed that the monolith had better selectivity for β-sitosterol and could be used for enrichment of β-sitosterol in food samples. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136 , 47683.
研究领域:
分析化学
·
食品科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Biomaterials Science & Engineering
·
2019
·
IF 4.511
Yin-Jia Cheng,Si-Yong Qin,Yi-Han Ma,Xiao-Sui Chen,Ai-Qing Zhang,Xian-Zheng Zhang
A multifunctional nanoplatform based on mesoporous silica nanoparticles (MSNs) was developed for combinational tumor therapy. Doxorubicin (DOX) was chosen as an antitumor drug and loaded into mesopores of MSNs via physical absorption. Then, a tumor-targeted fusion peptide conjugated with 2,3-dimethylmaleic anhydride (DTCPP) and a therapeutic peptide conjugated with 2,3-dimethylmaleic anhydride (DTPP) were introduced to the surface of MSNs as super-pH-sensitive nanovalves through disulfide linkages. The BSA adsorption assay confirmed the charge-reversal property of MSN-ss-DTPP&DTCPP nanoparticles at slightly acidic condition (pH 6.8) and superior stability in physiological environment (pH 7.4). According to the drug release research, both glutathione (GSH) and acidic condition are required for the accelerated drug release from DOX@MSN-ss-DTPP&DTCPP nanoparticles. Moreover, in vitro studies demonstrated the significantly reinforced tumor cellular uptake efficiency and mitochondrial disruption ability of DOX@MSN-ss-DTPP&DTCPP nanoparticles in tumor environment, in which DOX@MSN-ss-DTPP&DTCPP nanoparticles exhibited the preferred cytotoxicity toward αvβ3-positive human cervical carcinoma (HeLa) cells. We believe that the multifunctional dual-stimuli-sensitive MSN could provide an effective strategy for combinational tumor therapy.
研究领域:
纳米技术
·
癌症研究
·
药物递送
·
材料科学
·
生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ADVANCED MATERIALS
·
2024
·Vol. 36
·期 28
·2401589
·
IF 27.4
Yu Sun,Xiaoxia Le,Hui Shang,Ying Shen,Yue Wu,Qingquan Liu,Partick Théato,Tao Chen
Constructing an anti-counterfeiting material with non-interference dual optical modes is an effective way to improve information security. However, it remains challenging to achieve multistage secure information encryption due to the limited stimulus responsiveness and color tunability of the current dual-mode materials. Herein, a dual-mode hydrogel with both independently tunable structural and fluorescent colors toward multistage information encryption, is reported. In this hydrogel system, the rigid lamellar structure of poly(dodecylglyceryl itaconate) (pDGI) formed by shear flow-induced self-assembly provides the restricted domains wherein monomers undergo polymerization to form a hydrogel network, producing structural color. The introduction of fluorescent monomer 6-acrylamidopicolinate (6APA) as a complexation site provides the possibility of fluorescent color formation. The hydrogel's angle-dependent structural color can be controlled by adjusting the crosslinking density and water content. Additionally, the fluorescence color can be modulated by adjusting the ratio of lanthanide ions. Information of dual-mode can be displayed separately in different channels and synergistically overlayed to read the ultimate message. Thus, a multistage information encryption system based on this hydrogel is devised through the programed decryption process. This strategy holds tremendous potential as a platform for encrypting and safeguarding valuable and authentic information in the field of anti-counterfeiting.
研究领域:
材料科学
·
光学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子