SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
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2022
·
IF 4.831
Meng Wang,Jiao Wang,Nan Ma,Shuaibing Yu,Jinming Kong,Xueji Zhang
In this work, a new colorimetric method for the determination of Glutathione (GSH) on the basis of stable free radical 2,2,6,6 − tetramethylpiperidine − 1 − oxyl (TEMPO) oxidation of 3,3′,5,5′−tetramethylbenzizine (TMB) via copper(II) acetylacetonate (Cu(acac) 2 ) catalysis was proposed. TEMPO was catalyzed by Cu(acac) 2 to produce TEMPO + , then TEMPO + oxidized TMB to produce oxidized TMB (ox − TMB). The resulting ox − TMB showed blue and possessed a distinct absorption peak about 650 nm. Whereas, GSH prohibited the generation of ox − TMB through inhibiting TMB oxidation. As compared to the case that GSH was absent, significantly enhanced absorption was determined, and was proportional to GSH amount. On this basis, a qualitative and quantitative detection method of GSH with the naked eye and the microplate reader was achieved. The developed TEMPO − based method achieved GSH biosensing with improved sensitivity in a good specificity − manner. The limit of detection (LOD) was 90 μM via naked eye, and the microplate reader was 4.71 μM. And the stable free radical TEMPO possessed higher stability and lower toxicity than traditional oxidant of H 2 O 2 . Moreover, this TEMPO − based method achieved good results in the detection of GSH in human serums.
研究领域:
分析化学
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生物化学
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生物医学工程
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DOI
PubMed
高影响因子
Advanced Sustainable Systems
·
2021
·Vol. 5
·期 6
·2000297
·
IF 6.271
Ai-Di Cheng,Min-Hua Zong,Guang-Hui Lu,Ning Li
Laccase coupled with 2,2,6,6-tetramethylpiperidinyl-1-oxy (TEMPO) is a well-known catalytic system for the oxidation of alcohols to the carbonyl compounds. In this work, a simple yet effective solvent engineering strategy is developed to enable aromatic alcohols/aldehydes to be efficiently oxidized to carboxylic acids by a laccase-TEMPO system. Citrate buffer (100–300 m m , pH 6) rather than the widely used acetate buffer (pH 4–5) proves to be optimal for this purpose. The roles of citrate are discussed in laccase-TEMPO-catalyzed synthesis of carboxylic acids. 5-Hydroxymethylfurfural (HMF) of 200 m m is oxidized to 2,5-furandicarboxylic acid (FDCA), a top-value biobased chemical in the polymer industry, in 28 h with a yield of up to 97%. Of the 18 substrates examined, 11 alcohols are converted to target carboxylic acids with >90% yields by this method, with 2 alcohols giving >60% yields of carboxylic acids. Gram-scale preparation of FDCA and 5-methyl-2-pyrazinecarboxylic acid, an important drug intermediate, is demonstrated with total turnover numbers up to 110 000 for laccase and space-time yields up to 1.0 g/(L•h). This chemoenzymatic approach may be a promising alternative to traditional chemical oxidations for the synthesis of carboxylic acids.
研究领域:
生物化学
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酶工程
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绿色化学
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DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2024
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IF 7.7
Lei Dai,Yijiao Xue,Sihan Tian,Ping He,Pan Xie,Zhu Long,Guiqiang Fei,Zhirong Chen
The monitoring of foodborne bacterial contamination requires simple and convenient biosensors . This work describes a novel paper-based colorimetric biosensor for the rapid and sensitive bacteria detection. The biosensor was constructed via the encapsulation of D-alanyl-D-alanine capped gold nanoparticles (DADA-AuNPs) in a modified paper that was fabricated by the freeze-drying of TEMPO-oxidized cellulose nanofibers/cationic guar gum composite hydrogel-modified filter paper. The results indicated that the size of DADA-AuNPs largely determined the color of their aqueous system and they exhibited light red to dark red as their size increased from around 6 to 36 nm. All these different sized DADA-AuNPs turned into colorless when encountered with either S. aureus or E. coli . In particular, the smaller the DADA-AuNPs size, the faster the discoloration. The encapsulation of DADA-AuNPs into modified paper negligibly changed their responsiveness towards bacteria. In comparison to the original filter paper and oven-dried hydrogel-modified filter paper, the freeze-dried hydrogel-modified paper was demonstrated to be a better substrate for the encapsulation of DADA-AuNPs since they could be loaded with a larger amount of DADA-AuNPs in a faster way and showed a better perceivable color. This work demonstrated a promising paper-based colorimetric biosensor for the facile and rapid detection of bacteria.
研究领域:
食品科学
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纳米技术
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生物传感
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DOI
PubMed
高影响因子
MICROCHEMICAL JOURNAL
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2025
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IF 5.1
Shijin Zhou,Nan Ma,Kefeng Ma,Jinming Kong,Xueji Zhang,Huaixia Yang
Ultrasensitive quantitative detection of Staphylococcus aureus ( S. aureus ) is critically important for preventing food-borne illnesses caused by this pathogen. In this study, an electrochemical biosensor for accurate detection of S. aureus was developed for the first time by in situ ring-opening metathesis polymerization (ROMP) of bacterial surface proteins. In brief, the glassy carbon electrode (GCE) was functionalized via electrochemical reduction of aryl diazonium salts to provide binding sites for specific capture probe-aptamer. 2,2,6,6-tetramethylpiperidin-4-ylamine (TEMPO) was modified on the ROMP polymer by post-functionalization method to achieve signal amplification. In the concentration range of 1.0 × 10 1 CFU/mL ∼ 1.0 × 10 8 CFU/mL, the detection limit of the electrochemical biosensor for S. aureus was 2.2 CFU/mL. In addition, the sensor has excellent reproducibility and recognition ability, and can accurately detect S. aureus in the presence of a variety of bacteria. To validate practical utility, the biosensor was successfully applied to detect S. aureus in real food samples—including milk and orange juice—yielding high recovery rates and reliable quantification. The sensor adopts a mild and environmentally friendly ROMP signal amplification strategy and has excellent analytical performance, which has important potential in the field of accurate identification of food-borne pathogens.
研究领域:
分析化学
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生物传感器
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高分子化学
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电化学
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食品安全
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病原体检测
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产品关联
DOI
高影响因子
INDUSTRIAL CROPS AND PRODUCTS
·
2023
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IF 5.9
Zijun Zhang,Qimeng Jiang,Guihua Yang,Xv Zhang,Xingmao Jiang,Bo He,Jiachuan Chen
Film preservative packaging is one of common techniques to solve rot problem of fruits and vegetables in transit, storage and sale process. But traditional petroleum-based films have no long-lasting antibacterial properties and they are difficult to biodegrade. Herein, TEMPO-oxidized nanocellulose (TCNF) was used as green reducer and stabilizer to synthesize and immobilize silver nanoparticles (AgNPs) in one-pot method. Next the TCNF immobilized AgNPs was combined with chitosan to form antibacterial preservative composite film (CS/TCNF@AgNPs). The results show that CS/TCNF@AgNPs exhibited satisfied preservative effects for cherry tomatoes and strawberries . Notably, the composite film showed excellent antibacterial properties against E. coli and S. aureus and the accumulated release amount of AgNPs was only about 2.05% after 264 h. Furthermore, the composite film degraded almost completely in soil within 25 days. The cytotoxicity assay also exhibited favorable biocompatibility. Therefore, the composite film has potential application as a packaging material for fruit and vegetable antibacterial preservation.
研究领域:
材料科学
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食品科学
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环境科学
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DOI
高影响因子
Polymers
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2019
·Vol. 11
·期 12
·2076
·
IF 3.164
Junfeng Zhu,Ting Zhu,Huan Tuo,Wanbin Zhang
A novel nitroxyl radical polymer poly(TEMPO-acrylamide-co-sodium styrene sulfonate) (abbreviated as poly(TAm-co-SSS)) was synthesized using 4-acrylamido-2,2,6,6- tetramethylpiperidine (AATP) copolymerized with styrene sulfonate sodium (SSS). AATP was synthesized through a substitution reaction of acryloyl chloride. Meanwhile, poly(4-acrylamido-2,2,6,6-tetramethylpiperidine-1-nitroxyl radical) (PTAm) was prepared as a control sample. Then, the structures of products were characterized by nuclear magnetic resonance spectroscopy (1H-NMR), Fourier transform infrared spectroscopy (FT-IR), high performance liquid chromatography-mass spectrometry (HPLC-MS), differential scanning calorimetry (DSC), X-Ray photoelectron spectroscopy (XPS), and electron paramagnetic resonance (EPR), respectively. Additionally, the electrochemical impedance spectra (EIS) and the charge-discharge cycling properties were studied. The results demonstrated that the poly(TAm-co-SSS) with the side group of sodium sulfonate adjacent to TEMPO group exhibits a better charge-discharge cycling stability than that of the PTAm. Moreover, the charge specific capacity of the poly(TAm-co-SSS) is larger than that of the PTAm. Besides, the first coulombic efficiency of poly(TAm-co-SSS) is higher in comparison with that of PTAm. These superior electrochemical performances were ascribed to the synergistic effect of sulfonate ions group and nitroxyl radical structure, which benefits the improvement of charge carrier transportation of the nitroxyl radical polymers. Consequently, the nitroxyl radical poly(TAm-co-SSS) is promising for use in organic radical battery materials, based on the good electrochemical properties.Keywords:nitroxyl radical polymer;poly(TEMPO-acrylamide-co-sodium styrene sulfonate);electrochemical properties;cathode material;organic radical battery
研究领域:
材料科学
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电化学
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产品关联
DOI
PubMed
高影响因子
Food Packaging and Shelf Life
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2025
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IF 10.6
Huajian Ou,Lu Chen,Qiaohui Zeng,Wangsheng Qiu,Zihao Lin,Konglong Feng,Guang Liu,Ping Qi,Weijuan Huang,Jing Jing Wang
A novel photodynamic inactivation (PDI)-mediated antimicrobial packaging film (APF) was successfully fabricated by covalently grafting 5-aminolevulinic acid (ALA) onto the surface of TEMPO-oxidized chitin film (O-CT). The O-CT/ALA films exhibited good mechanical strength, remarkable UV-blocking capacity, high thermal stability, and chemical stability. Notably, the grafted ALA induced the generation of endogenous protoporphyrin IX in bacterial cells, and they were excited to produce ROS under the irradiation of blue light. Consequently, the films inactivated > 7.00 log CFU/mL of Vibrio parahaemolyticus and 3.29 log CFU/mL of Staphylococcus aureus , as well as efficiently eradicated the bacterial biofilms by disrupting their architectural structures. More importantly, the films inhibited the growth of native bacteria in salmon during storage at 4 °C and 25 °C. Therefore, the PDI-mediated APF is valid in inactivating bacteria and ensuring food quality in the food industry.
研究领域:
食品科学
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微生物学
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材料科学
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抗菌技术
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光动力疗法
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产品关联
DOI
高影响因子
Materials
·
2025
·Vol. 18
·期 15
·3624
·
IF 3.2
Yanwen Ren,Qianqian Zheng,Cuicui He,Jingjing Nie,Binyang Du
Aqueous organic redox flow batteries (AORFBs) represent an advancing class of electrochemical energy storage systems showing considerable promise for large-scale grid integration due to their unique aqueous organic chemistry. However, the use of small-molecule active materials in AORFBs is significantly limited by the issue of stability and crossover. To address these challenges, we designed a high-water-solubility polymer cathode material, P-T-S, which features a polyvinylimidazole backbone functionalized with 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) and sulfonate groups. P-T-S exhibits a solubility of 34 Ah L−1in water and 31 Ah L−1in 1.0 M NaCl aqueous solution (NaClaq). When paired with methyl viologen to assemble a pH-neutral AORFB with a theoretical capacity of 15 Ah L−1, the system exhibits a material utilization rate of 92.0%, an average capacity retention rate of 99.74% per cycle (99.74% per hour), and an average Coulombic efficiency of 98.69% over 300 consecutive cycles at 30 mA cm−2. This work provides a new design strategy for polymer materials for high-performance AORFBs.
研究领域:
储能
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电化学
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聚合物材料
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可再生能源
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电池技术
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DOI
PubMed
高影响因子
RSC Advances
·
2020
·Vol. 10
·期 44
·26142-26150
·
IF 3.119
Binyu Xu,Samuthirarajan Senthilkumar,Wei Zhong,Zhongquan Shen,Chunxin Lu,Xiaoming Liu
In this work, core–shell Fe3O4@Cu2O and Fe3O4@Cu2O–Cu nanomaterials for aerobic oxidation of benzylic alcohols are reported with 2,2,6,6-tetramethylpiperidine-N-oxyl (TEMPO) and N-methylimidazole (NMI) as the co-catalysts. To anchor Cu2O nanoparticles around the magnetic particles under solvothermal conditions, the magnetic material Fe3O4 was modified by grafting a layer of L-lysine (L-Lys) to introduce –NH2 groups at the surface of the magnetic particles. With amine groups as the anchor, Cu(NO3)2 was used to co-precipitate the desired Cu2O by using ethylene glycol as the reducing agent. Prolonging the reaction time would lead to over-reduced forms of the magnetic materials in the presence of copper, Fe3O4@Cu2O–Cu. The nanomaterials and its precursors were fully characterized by a variety of spectroscopic techniques. In combination with both TEMPO and NMI, these materials showed excellent catalytic activities in aerobic oxidation of benzylic alcohols under ambient conditions. For most of the benzylic alcohols, the conversion into aldehydes was nearly quantitative with aldehydes as the sole product. The materials were recyclable and robust. Up to 7 repeat runs, its activity dropped less than 10%. The over-reduced materials, Fe3O4@Cu2O–Cu, exhibited slightly better performance in durability. The magnetic properties allowed easy separation after reaction by simply applying an external magnet.
研究领域:
材料科学
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催化
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化学工程
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纳米技术
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DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
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2024
·
IF 8.3
Badusha Mohamad Ali,Ziqi Yu,Zhengyuan Tao,Tangxin Zhang,Lei Wang,Chenbing He,Hao Zhang,Jianli Wang
The novel 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) groups immobilized on functional polymers or nanoparticles emerged as potential Pickering interfacial catalysts (PICs) for effective catalysis in biphasic systems. In this study, a snowman-shaped Janus-structured polymer with TEMPO-anchored nanohybrid particles (SM-JPP-TEMPO) was prepared and employed as a potential PIC in the Anelli–Montanari system for the selective oxidation of alcohol. The amphiphilic character of SM-JPP-TEMPO particles plays a dual role as an emulsifier and catalyst in the Pickering emulsion. As a result, it enables smaller droplets (102 μm) at the water-in-oil (W/O) interface and reduces the interfacial tension from 26.58 to 17.38 mN/m, which improves the stability of the Pickering emulsion system. This constructed Pickering emulsion microreactor offers a larger interface contact area and shortens the mass transfer distance of the substrate of cinnamyl alcohol, which significantly enhances the catalytic conversion at the Anelli–Montanari oxidation system, thus achieving remarkable conversion efficiency of (92.3%) with excellent selectivity (99%) in static (stirring-free) condition. It was found that the Janus nanohybrid catalyst (SM-JPP-TEMPO) enhanced 1.29-fold catalytic efficiency compared to the TEMPO grafted spherical polystyrene nanoparticle (PS-NPs-TEMPO) catalyst (72%). Moreover, after seven consecutive cycles, the Janus nanocatalyst (SM-JPP-TEMPO) maintained the conversion significantly. Hence, these results collectively highlight that the amphiphilic SM-JPP-TEMPO catalyst provides an efficient and eco-friendly strategy for the intensification of liquid–liquid biphasic reaction systems for potential applications in industries.
研究领域:
化学工程
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催化科学
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DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2025
·
IF 8.5
Hao Wu,Jun Huang,Lifang Guo,Pu Ma,Yu Wang,Yanchen Zhu,Huamin Zhai,Hao Ren
The high-performance retention and drainage systems for papermaking is critical for achieving sustainability in papermaking. This study was aimed at examining the potential of 2,2,6,6-tetramethylpiperidine-1-oxyl oxidized cellulose nanofibrils (TOCNs), characterized by high carboxyl content, strong negative charge, and large specific surface area, as a replacement for colloidal silica (SiO 2 ) in the classic cationic polyacrylamide (CPAM)/SiO 2 /anionic polyacrylamide (APAM) system (CPAM/SiO 2 /APAM) in papermaking. The replacement objective was to improve the retention and drainage performance during papermaking and enhance paper sheet strength. The retention and drainage behavior of the CPAM/TOCNs/APAM system in papermaking and its impact on sheet strength were investigated. The results show that compared with the CPAM/SiO 2 /APAM system, the CPAM/TOCNs/APAM system exhibits superior retention and drainage ability, along with greater sheet strength enhancement. Although the incorporation of hydrophobic cellulose polyglycidyl methacrylate grafted fibers (CPGMAs) slightly reduce sheet strength, it significantly improves the drainage. Moreover, a synergistic effect between CPAM/TOCNs/APAM and CPGMAs on retention and drainage performance is identified. An innovative CPAM/TOCNs/APAM@CPGMAs system was developed to facilitate retention and drainage, achieving 20–30 % higher drainage efficiency, 10–15 % higher filler retention, and enhanced sheet strength than the CPAM/SiO 2 /APAM@CPGMAs system. This system holds prospects for environmentally friendly, efficient, and high-quality papermaking.
研究领域:
材料科学
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化学工程
·
造纸技术
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纳米技术
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高分子科学
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产品关联
DOI
PubMed
高影响因子
COMPOSITES SCIENCE AND TECHNOLOGY
·
2018
·
IF 5.16
Tao Wu,Bing Cai,Jinyu Wang,Chenggang Zhang,Zhuqun Shi,Quanling Yang,Guo-Hua Hu,Chuanxi Xiong
High-performance and environment-friendly biomass-based composite films have drawn much attention recently. Here, bio-nanocomposites of TEMPO-oxidized cellulose nanofibrils (TOCNs) reinforced with layered double hydroxides (LDHs) were prepared through an environmentally benign pathway by aqueous dispersion. The results showed that LDHs could be uniformly dispersed in the cellulose nanofibril matrix to form an intercalated nanolayered structure due to good compatibility and the formation of ionic and hydrogen bonds between LDHs with positive charges and TOCNs with negative charges. The TOCN-LDH composite films exhibited high light transmittance, which exceeded 80% with an LDHs content of less than 10%. Moreover, the incorporation of LDHs improved not only the mechanical properties of the cellulose nanofibrils, but also their thermal stability, flame retardancy and hydrophobicity . More specifically, the highest Young's modulus and tensile strength reached 39.3 GPa of TOCN-LDH20 and 358 MPa of TOCN-LDH5, which were 364% and 178% of the neat TOCN film, respectively. The water contact angle and limiting oxygen index of the TOCN-LDH composite film increased from 46° to 103°, and from 25 to 31, respectively, with the LDH content increase from 0 to 20 wt%.
研究领域:
材料科学
·
纳米技术
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环境科学
·
复合材料
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）