BIOPROCESS AND BIOSYSTEMS ENGINEERING
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2018
·Vol. 41
·期 9
·1347-1354
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IF 2.139
Tang Xiao-Ling,Liu Xiao,Suo Hui,Wang Zhi-Chao,Zheng Ren-Chao,Zheng Yu-Guo
The tyrosine phenol lyase (TPL) catalyzed synthesis of L-DOPA was regarded as one of the most economic route for L-DOPA synthesis. In our previous study, a novel TPL from Fusobacterium nucleatum ( Fn -TPL) was exploited for efficient biosynthesis of L-DOPA. However, the catalytic efficiency decreased when the reaction system expanded from 100 mL to 1 L. As such, the bioprocess for scale-up production of L-DOPA was developed in this study. To increase the stability of substrate and product, as well as decrease the by-product formation, the optimum temperature and pH were determined to be 15 °C and pH 8.0, respectively. The initial concentration of pyrocatechol, pyruvate and ammonium acetate was fixed at 8, 5 and 77 g/L and a fed-batch approach was applied with sodium pyruvate, pyrocatechol and ammonium acetate fed in a concentration of 5, 5 and 3.5 g/L, respectively. In addition, L-DOPA crystals were exogenously added to inhibit cell encapsulation by the precipitated product. The final L-DOPA concentration reached higher than 120 g/L with pyrocatechol conversion more than 96% in a 15-L stirred tank, demonstrating the great potential of Fn -TPL for industrial production of L-DOPA.
研究领域:
生物化学
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微生物学
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制药工程
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产品关联
DOI
PubMed
高影响因子
Analytical Methods
·
2015
·Vol. 7
·期 15
·6103-6108
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IF 1.821
Yuling Hu,Dongmei Wang,Gongke Li
Inspired by the bioadhesive and redox properties of the 3,4-dihydroxy-phenylalanine (DOPA) contained in marine mussels, a facile, rapid and economic colorimetric strategy for Hg2+ detection was developed. The abundant catechol chains on the surface of Ag@DOPA can reduce Hg2+ to Hg0 and form a Ag@DOPA@Hg nanostructure with the deposition of Hg0. The nanostructures of Ag@DOPA and Ag@DOPA@Hg were confirmed by X-ray photoelectron spectroscopy, transmission electron microscopy, elemental mapping and Fourier transform infrared spectroscopy. The formation of the Ag@DOPA@Hg nanostructure causes a change in the color of the Ag@DOPA colloids from golden yellow to purple blue, making it directly possible to detect Hg2+ using a colorimetric strategy within 5 minutes. With increasing concentrations of Hg2+ from 10 nM to 4 μM, the surface plasmon resonance absorbance peak of the Ag@DOPA colloids decreased in intensity and exhibited a good linear relationship with the Hg2+ concentration. The limit of detection was determined as 5 nM. Furthermore, this response was found to be highly selective for Hg2+ as the absorption spectrum was not affected by other metal ions such as Pb2+, Cr3+, Cu2+, Al3+, Ni2+, Co2+, etc. The excellent stability, selectivity and sensitivity of this strategy offer analytical practicability for Hg2+ detection in real water samples with recoveries in the range of 104–105% and cosmetic samples with recoveries in the range of 85–103%.
研究领域:
分析化学
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环境科学
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材料科学
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DOI
高影响因子
CHINESE JOURNAL OF CHEMICAL ENGINEERING
·
2024
·
IF 3.7
Yue Zhou,Wenjun Li,Hongjun Hu,Zhaohui Wang,Zhaoliang Cui
The membrane aeration biofilm reactor (MABR) represents an innovative approach to wastewater treatment, integrating gas separation membranes with biofilm process and demonstrating effectiveness in treating wastewater rich in ammonia nitrogen. In this system, hollow fiber membranes are essential, serving as a substrate for biofilm attachment while facilitating oxygen transfer to microorganisms through aeration, hydrophobic microporous membranes are utilized in MABR applications. This study focuses on the use of poly-4-methyl-1-pentene (PMP) hollow fiber membranes, which exhibit superior oxygen permeation capabilities compared to traditional hydrophobic microporous membranes. To overcome the challenges posed by the hydrophobic nature and low bubble point of PMP microporous membranes, a hydrophilic modification was conducted using dopamine/poly(ethyleneimine) (DOPA/PEI) co-deposition to enhance microbial adhesion on the membrane surface. The composite membrane modified with DOPA/PEI exhibited an approximately 20% higher NH 4 + -N removal efficiency than the unmodified membrane. These findings suggest that the incorporation of DOPA/PEI significantly improves MABR performance, underscoring its potential for further research and development in membrane technology for MABR.
研究领域:
环境工程
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生物技术
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膜科学
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DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2015
·Vol. 39
·期 9
·6919-6924
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IF 3.086
Ya Chen,Juanjuan Xu,Cui Chen,Dongmei Guo,Yingzi Fu
A new nanocomposite of L-tryptophan functionalized graphene-supported platinum nanoparticles (L-Trp-rGO@PtNPs) was synthesized utilizing a facile ultrasonic method via π–π conjugate action between graphene-supported platinum nanoparticles and L-tryptophan (L-Trp) molecules. The prepared nanomaterial, which dispersed well in water and presented excellent conductivity, was modified on a glassy carbon electrode (L-Trp-rGO@PtNPs/GCE) for the chiral sensing of DOPA enantiomers. The immobilization process of L-Trp-rGO@PtNPs/GCE was characterized by cyclic voltammetry, electrochemical impedance spectroscopy, scanning electron microscopy, ultraviolet-visible (UV-vis) spectrometry and Raman spectroscopy. The electrochemical reactions of DOPA enantiomers were investigated via differential pulse voltammetry. The proposed electrochemical method showed excellent enantiospecificity for DOPA enantiomers and exhibited a stronger enantiospecificity for D-DOPA. In addition, the experimental parameters such as the concentration, the amount of L-Trp-rGO@PtNPs and the pH values were optimized. Under optimum conditions, the linear response ranges for the discrimination of DOPA were from 5.0 × 10−8 to 5.0 × 10−3 mol L−1 with a detection limit of 1.7 × 10−8 mol L−1 (S/N = 3).
研究领域:
材料科学
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分析化学
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生物化学
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DOI
高影响因子
Journal of Materials Chemistry B
·
2023
·Vol. 11
·期 47
·11235-11250
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IF 7
Chan Chen,Haisheng Ren,Weikang Tang,Mengqi Han,Qinfei Chen,Hong Zhou,Jiadong Chen,Yuyue Gao,Wenbin Liu
L-3,4-Dihydroxyphenylalanine (L-DOPA) is widely used in Parkinson's disease treatment and is therefore in high demand. Development of an efficient method for the production of L-DOPA is urgently required. Nanozymes emulating tyrosine hydroxylase have attracted enormous attention for biomimetic synthesis of L-DOPA, but suffered from heterogeneity. Herein, a spherical porous iron–nitrogen–carbon nanozyme was developed for production of L-DOPA. Tannic acid chelated with ferrous ions to form a tannin-iron coordination framework as a carbon precursor. Iron and nitrogen co-doped carbon nanospheres were assembled via an evaporation-induced self-assembly process using urea as a nitrogen source, F127 as a soft template, and formaldehyde as a crosslinker. The nanozyme was obtained after carbonization and acid etching. The nanozyme possessed a dispersive iron atom anchored in the Fe–N coordination structure as an active site to mimic the active center of tyrosine hydroxylase. The material showed spherical morphology, uniform size, high specific surface area, a mesoporous structure and easy magnetic separation. The structural properties could promote the density and accessibility of active sites and facilitate mass transport and electron transfer. The nanozyme exhibited high activity to catalyze the hydroxylation of tyrosine to L-DOPA as tyrosine hydroxylase in the presence of ascorbic acid and hydrogen peroxide. The titer of DOPA reached 1.2 mM. The nanozyme showed good reusability and comparable enzyme kinetics to tyrosine hydroxylase with a Michaelis–Menten constant of 2.3 mM. The major active species was the hydroxyl radical. Biomimetic simulation of tyrosine hydroxylase using a nanozyme with a fine structure provided a new route for the efficient production of L-DOPA.
研究领域:
生物化学
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材料科学
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医学
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DOI
PubMed
高影响因子
COLLOIDS AND SURFACES B-BIOINTERFACES
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2024
·
IF 5.4
Yu Han,Li-Hui Sun,Bo Cai,Ming Xia,Chun-Quan Zhu,Dong-Song Li
Large bone defects are a major clinical challenge in bone reconstructive surgery. 3D printing is a powerful technology that enables the manufacture of custom tissue-engineered scaffolds for bone regeneration. Electrical stimulation (ES) is a treatment method for external bone defects that compensates for damaged internal electrical signals and stimulates cell proliferation and differentiation. In this study, we propose a simple, reliable, and versatile strategy to prepare multifunctional 3D printed scaffold combined with ES for bone defect therapy. Firstly, scaffolds composed of polycaprolactone (PCL) and Ti 3 C 2 were prepared by 3D printing technology, and then a stromal cell derived factor 1 (SDF1) containing DOPA tag was loaded onto the scaffold surface. Ti 3 C 2 was selected as the electrode component because of its excellent electrical conductivity. The selection of DOPA-modified SDF-1(DOPA-SDF1) can improve the material binding ability and exert long-term stem cell recruitment function. The results show that prepared 3D printed scaffold (DOPA-SDF1@PCL#Ti 3 C 2 ) has good hydrophilicity, electrical conductivity, antibacterial property, biocompatibility and stem cell recruitment ability. Furthermore, the expression of osteogenic specific genes in scaffold surface cells was significantly increased when pulse ES (PES) treatment was applied. The results of tibial plateau defect repair experiment showed that DOPA-SDF1@PCL#Ti 3 C 2 scaffold can significantly promote the formation of new bone and collagen fibres. When the DOPA-SDF1@PCL#Ti 3 C 2 scaffold was used in combination with PES therapy, the bone defect regeneration rate was further improved. This kind of scaffold could provide a new strategy for promoting the healing of large bone injuries and could expand the application of adjuvant therapy such as PES.
研究领域:
组织工程
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生物材料
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再生医学
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生物医学工程
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骨科
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产品关联
DOI
PubMed
高影响因子
ELECTROCHIMICA ACTA
·
2024
·
IF 5.5
Wenzhu Kuang,Hongxia Luo,Zhiwei Zhu
A range of electrochemical sensors capable of enantiomer discrimination have been developed, but the creation of their electrochemical interfaces remains complex. This often entails combining externally introduced chiral centers with conductive materials. This study marks a significant departure from this approach by exploiting the inherent chirality of single-walled carbon nanotubes (SWCNTs) for enantiomer discrimination. We have crafted a miniaturized, enantioselective electrochemical microsensor by seamlessly integrating high-purity SWCNTs, possessing inherent chirality, with an ultra-sensitive carbon fiber microelectrode. Using differential pulse voltammetry, we observed a notable difference in peak current, highlighting the sensor's precise ability to distinguish between enantiomers of 3,4-dihydroxyphenylalanine (DOPA). Furthermore, we investigated the intricacies of the interplay between enantioselective interfaces and the molecules under discrimination, offering deeper insights into the mechanisms governing this phenomenon. This study provides substantial momentum into the realm of enantioselective electrochemical sensing and sheds light on the unique attributes of inherently chiral carbon nanotubes in such applications. This paves the way for a new breed of chiral sensors that are simpler, more efficient, and cost-effective.
研究领域:
材料科学
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分析化学
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纳米技术
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电化学
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产品关联
DOI
高影响因子
Polymer Chemistry
·
2016
·Vol. 7
·期 30
·4964-4974
·
IF 5.687
Liying Wang,Guangji Li,Yinlei Lin,Zixun Zhang,Zhifeng Chen,Shuqing Wu
A novel route to construct stable and durable anti-adhesion surfaces was explored via a combination of the excellent anti-adhesion performance of zwitterionic betaine macromolecules with the strong adhesion of DOPA or its derivatives to various substrates. The zwitterionic betaine macromolecules bearing a thiol group poly(DMAPMAPS-co-BAC) and a DOPA derivative DMA containing a catechol anchor group and a double bond were first designed and synthesized. The poly(DMAPMAPS-co-BAC)-grafted surfaces were then fabricated via the interfacial thiol–ene photoclick reaction between poly(DMAPMAPS-co-BAC) and DMA anchored onto substrate (i.e., Glass slides and flat PET sheets) surfaces. The chemical formation of each layer on the surfaces was confirmed by XPS and ATR-FTIR analyses. Their morphologies and wettability were characterized. The results indicate that, compared with the original surfaces, the modified surfaces possess an increased nanoscale roughness; the WCA and OCA values on the modified Glass/PET surfaces can reach 10°/12° and 156°/162°, respectively, showing their strong hydrophilicity and excellent underwater superoleophobicity. The anti-oil-fouling and antifogging properties were investigated and the anti-bacterial adhesion properties were evaluated by bacterial adhesion tests using E. coli and S. aureus as test bacteria, respectively. The results show that the modified surfaces possess obvious anti-oil-fouling and antifogging properties and a strong ability to resist bacterial adhesion with a long term stability. It suggests that such a facile yet universal strategy based on interfacial thiol–ene photoclick chemistry could offer an effective solution to the poor stability of anti-adhesion surfaces modified with ultralow-adherent zwitterionic betaine macromolecules, and could be applicable to a wide variety of substrates.
研究领域:
材料科学
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生物医学工程
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DOI
高影响因子
BIOMATERIALS
·
2024
·
IF 12.8
Zhaodi Liu,Yihang Ding,Yuan Ding,Weilin Wang,Zhengwei Mao,Lisha Yu
Tissue adhesives have attracted significant interest in the field of hemostasis. However, challenges including weak tissue adhesion, inadequate biocompatibility, and instability limit their clinical applications. Here, we have developed a gelatin-DOPA-knob/fibrinogen hydrogel inspired by the fibrin polymerization and mussel adhesion, resulting in a biocompatible bioadhesive with outstanding adhesion performance and great storage stability. This strategy involves modifying gelatin with knob peptides and catechol groups inducing crosslinking with fibrinogen to form a hydrogel via knob-hole interactions, and enhancing interfacial adhesion performance by interacting with the blood-covered tissue through catechol groups and knob peptides. This hydrogel exhibits rapid gelation, enhanced mechanical strength and adhesion properties, compared to the commonly used fibrin glue in surgery. The hydrogel significantly reduces the time required to hemostasis and the amount of blood loss in severe hemorrhage models. It ensures superior hemostatic efficacy, excellent biocompatibility, and long-term storage stability, which holds significant promise in medical settings.
研究领域:
生物材料
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组织工程
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止血
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生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY
·
2021
·
IF 6.064
Yuxi Lu,Shuai Wang,Hong Zhong
Wolframite is often associated with calcium bearing minerals, leading to low grade, while conventional anionic collectors are hard to realize their efficient flotation separation, thus the effective structural modification of cationic collectors provides a new insight into enhancing the comprehensive development of wolframite resources. In this study, a surfactant 3-dodecyloxy propyl amidoxime (DOPA) was designed and first used as the collector in flotation separation of wolframite from fluorite and calcite. Computational calculations basically proved the correctness of predictions about the performances of DOPA. Micro-flotation tests indicated that compared to DDA and conventional anionic collector benzohydroxamic acid (BHA), DOPA possessed superior collecting ability to wolframite and excellent selectivity against fluorite and calcite at low concentration, with no frother or activator employed, which is supposed to be an efficient collector for separating wolframite from calcium bearing minerals. The separation mechanisms of DOPA between wolframite and fluorite/calcite were further probed, revealing that besides the electrostatic attraction between DOPA and wolframite, DOPA could chemisorb onto wolframite surfaces by forming five-membered ring toward the surface cation site Fe or Mn, with no significant interaction observed on fluorite/calcite surfaces, resulting to the excellent separation performance.
研究领域:
矿物加工工程
·
材料科学与工程
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Pengxu Wang,Qing Liu,Wenliang Fu,Chao Zhang,Guiling Cai,Weiwei Xing,Hongliang Dai,Hongya Geng,Donggang Xu
Marine mussels have evolved the secretion of diversified mussel foot proteins to firmly attach to wet, salt-crusty, corroded, and fouled surfaces. Biomimicry of this robust wet adhesion via translating sticky biological molecules is still at an impasse mainly due to the lack of available materials and methodology to fully validate the underline mechanisms of adhesion and cohesion. Increasing sources of evidence have shown that the pair structure of protonated 3,4-dihydroxyphenylalanine (DOPA) and lysine contributes to the adhesion on substrates. However, it is still an uncultivated field to study the roles of those commonly distributed lysine and non-lysine pair structures in the adhesion to different surfaces, while remaining the intermolecular cohesion strength of the pair structures. Herein, the adhesive and cohesive properties of precisely designed single-molecule domains were systematically analyzed using single-molecule force spectroscopy after surface modification of probe tips. It was revealed a record-high adhesion force of ∼ 1000 pN for DOPA-lysine on cation-rich substrates (mica) and tyrosine-Lys on cation-deficient substrates (hydrophilic modified silicon nitride, Si 3 N 4 (OH)) due to an identified hydrophobic force. DOPA-phenylalanine and DOPA-tryptophan pairs were found to show versatile strong adhesion to both cation-rich and -deficient substrates, spanning from 750 pN to 2250 pN. Furthermore, our results revealed that Phe-Lys had an extraordinarily robust cohesion strength, up to 12,000 pN due to cation-π interactions. This study broadens our view of peptides adhesion, provides single molecule proofs toward understanding the mechanism of pair structures in natural adhesive proteins, as well as the design principles of the artificial adhesive layer.
研究领域:
材料科学
·
生物物理学
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仿生学
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粘附科学
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产品关联
DOI
高影响因子
COMBUSTION SCIENCE AND TECHNOLOGY
·
2024
·
IF 1.7
Lianquan Suo,Zhilin Xi,Tong Xia,Tao Chen,Jiawei Han
A new type of biomass environmentally friendly hydrosol (DEP) was proposed to inhibit coal spontaneous combustion (CSC). The DEP consists of two parts, the PDopa side chain solution formed by the redox reaction of Dopa and EGCG and the main chain sol solution formed by the free radical polymerization of AA under the action of APS initiator. The −COOH, −NH2, and −OH in Dopa can be grafted onto the skeleton of the main chain via double strong hydrogen bonding interactions with the −COOH group in PAA to form a stable three-dimensional cross-linked network structure. DEP can inhibit CSC through three aspects: oxygen isolation, increasing the activation energy of coal oxidation, scavenging active groups and free radicals. The calculation simulation results show that EGCG in DEP can remove various active free radicals with lower activation energy at room temperature, breaking the chain cycle reaction of coal spontaneous combustion, which proves its high efficiency. This study provides a new way to apply mussel-inspired adhesion mechanisms to the prevention of CSC.
研究领域:
能源科学
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环境科学
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材料科学
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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）