MICROCHIMICA ACTA
·
2018
·Vol. 185
·期 3
·1-9
·
IF 5.705
Wang Wei,Jayachandran Silambarasan,Li Mengru,Xu Shenghao,Luo Xiliang
An electrochemical biosensor for the detection of microRNA was prepared via chemical grafting of a Methylene Blue labeled reporter (MB-Rep) duplex onto a nanostructured surface that was obtained by electrodeposition of cobalt oxide and poly(o-phenylenediamine). This is followed by the attachment of hyaluronic acid and gold nanoclusters. In the presence of the target (microRNA), the probe-target duplex and the MB-Rep hairpin are formed. These will displace the labeled reporter from the sensor surface, and this results in a decrease of the amperometric signal for MB at a typical working voltage of −0.28 V (vs. Ag/AgCl). The electrode modified with hyaluronic acid possesses a large electroactive surface area and an excellent antifouling property. This makes it useful for ultrasensitive quantitation of microRNA even in complex biological media. The sensor has a linear response in the 100 f. to 0.1 μM microRNA concentration range, and a 33.3 f. detection limit. It was successfully applied to the determination of microRNA in cancer cells.
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研究领域:
生物化学
·
电化学
·
纳米技术
·
癌症诊断
✓ 已验证
DOI
PubMed
高影响因子
APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY
·
2021
·Vol. 195
·期 4
·2432-2450
·
IF 2.926
Zhang Yueqi,Ding Liping,Yan Zhenzhen,Zhou Dandan,Jiang Junwei,Qiu Jiarong,Xin Zhihong
An alkaline esterase, designated as EstXT1, was identified through functional screening from a metagenomic library. Sequence analysis revealed that EstXT1 belonged to the family VIII carboxylesterases and contained a characteristic conserved S-x-x-K motif and a deduced catalytic triad Ser56-Lys59-Tyr165. EstXT1 exhibited the strongest activity toward methyl ferulate at pH 8.0 and temperature 55°C and retained over 80% of its original activity after incubation in the pH range of 7.0–10.6 buffers. Biochemical characterization of the recombinant enzyme showed that it was activated by Zn 2+ and Co 2+ metal ion, while inhibited by Cu 2+ and CTAB. EstXT1 exhibited significant promiscuous acyltransferase activity preferred to the acylation of benzyl alcohol acceptor using short-chain p NP-esters (C2-C8) as acyl-donors. A structure–function analysis indicated that a WAG motif is essential to acyltransferase activity. This is the first report example that WAG motif plays a pivotal role in acyltransferase activity in family VIII carboxylesterases beside WGG motif. Further experiment indicated that EstXT1 successfully acylated cyanidin-3-O-glucoside in aqueous solution. The results from the current investigation provided new insights for the family VIII carboxylesterase and lay a foundation for the potential applications of EstXT1 in food and biotechnology fields.
研究领域:
生物化学
·
生物技术
·
酶学
·
食品科学
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DOI
PubMed
高影响因子
MICROCHIMICA ACTA
·
2020
·Vol. 187
·期 6
·1-9
·
IF 6.232
Li Xiaomeng,Kong Weisu,Qin Xia,Qu Fengli,Lu Limin
A facile and sensitive self-powered cathodic photoelectrochemical (PEC) aptasensor is reported for the detection of prostate-specific antigen (PSA) based on CuO-Cu 2 O nanowire array grown on Cu mesh (CuO-Cu 2 O NWA/CM) as electrode. The mixed narrow band gaps of the CuO-Cu 2 O heterostructure ensured its wide absorption band, effective electron/hole separation, and high photocatalytic activity in the visible region. In addition, nanowires directly grown on the substrate provided high specific surface area and exposed abundant active sites, thus guaranteeing its high photocatalytic efficiency. Therefore, the self-powered sensor exhibited favorable analytical performance with fast response, wide linear ranges of 0.01 to 5 ng/mL and 5 to 100 ng/mL, an acceptable detection limit of 3 pg/mL, and reasonable selectivity and stability. The proposed CuO-Cu 2 O NWA/CM can be considered a promising visible light-responsive photoactive material for fabrication of PEC aptasensor with high performance.
a Schematic illustration of construction process of PEC sensing platform based on the CuO-Cu 2 O composite for PSA detection. b Schematic mechanism of the operating PEC system.
研究领域:
分析化学
·
生物传感器
·
纳米材料
·
癌症诊断
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2021
·Vol. 56
·期 10
·6083-6094
·
IF 4.22
Liu Mei,Guo Rong,Ma Yue
Polyethyleneimine (PEI) is known for its antibacterial properties and ease of modification. How to improve the specific antibacterial activity of PEI with low toxicity is a research hotspot. In this work, the PEI was used to synthesize a fucose-modified polyethyleneimine copolymer particles (Fuc-PEI CPs) via nucleophilic addition between primary amine and aldehyde groups. Fucose (Fuc) can capture Pseudomonas aeruginosa ( P. aeruginosa ) with LecB, which has a good targeting property toward P. aeruginosa. The Fuc-PEI CPs’ antibacterial activity was investigated by plate counting method. Compared with unmodified PEI, Fuc-PEI CPs (2.5 μg/mL) showed unique bactericidal ability against P. aeruginosa , and less cytotoxicity and excellent biocompatibility. The antimicrobial mechanism indicated that the improvement of PEI antibacterial activity against P. aeruginosa ascribed to the Fuc’s unique recognition of bacteria and PEIs’ ability to destroy the cell membrane of bacteria. The Fuc-PEI CPs as a new antibacterial agent shed light on the constructing a novel antibacterial pathway for killing P. aeruginosa .
研究领域:
微生物学
·
材料科学
·
药学
✓ 已验证
DOI
高影响因子
JOURNAL OF NANOBIOTECHNOLOGY
·
2022
·Vol. 20
·期 1
·1-12
·
IF 9.429
Yu Rongjun,Xue Jian,Wang Yang,Qiu Jingfu,Huang Xinyi,Chen Anyi,Xue Jianjiang
In this work, Ti 3 C 2 T x MXene was identified as efficient nanozyme with area-dependent electrocatalytic activity in oxidation of phenolic compounds, which originated from the strong adsorption effect between the phenolic hydroxyl group and the oxygen atom on the surface of Ti 3 C 2 T x MXene flake. On the basis of the novel electrocatalytic activity, Ti 3 C 2 T x MXene was combined with alkaline phosphatase to construct a novel cascading catalytic amplification strategy using 1-naphthyl phosphate (1-NPP) as substrate, thereby realizing efficient electrochemical signal amplification. Taking advantage of the novel cascading catalytic amplification strategy, an electrochemical biosensor was fabricated for BCR/ABL fusion gene detection, which achieved excellent sensitivity with linear range from 0.2 fM to 20 nM and limit of detection down to 0.05 fM. This biosensor provided a promising tool for ultrasensitive fusion gene detection in early diagnosis of chronic myelogenous leukemia and acute lymphocytic leukemia. Moreover, the manageable catalytic activity of MXene broke a path for developing nanozymes, which possessed enormous application potential in not only electrochemical analysis but also the extensive fields including organic synthesis, pollutant disposal and so on. Graphical Abstract
研究领域:
生物医学工程
·
纳米材料科学
·
癌症早期诊断
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF NANOPARTICLE RESEARCH
·
2013
·Vol. 15
·期 9
·1-9
·
IF 2.175
Chen Zhanguang,Wang Zhen,Chen Xi,Xu Haixiong,Liu Jinbin
In this contribution, novel chitosan-stabilized gold nanoparticles (AuNPs) were prepared by mixing chitosan with citrate-reductive AuNPs under appropriate conditions. The as-prepared chitosan-stabilized AuNPs were positively charged and highly stably dispersed in aqueous solution. They exhibited weak resonance light scattering (RLS) intensity and a wine red color. In addition, the chitosan-stabilized AuNPs were successfully utilized as novel sensitive probes for the detection of heparin for the first time. It was found that the addition of heparin induced a strong increase of RLS intensity for AuNPs and the color change from red to blue. The increase in RLS intensity and the color change of chitosan-stabilized AuNPs caused by heparin allowed the sensitive detection of heparin in the range of 0.2–60 μM (~6.7 U/mL). The detection limit for heparin is 0.8 μM at a signal-to-noise ratio of 3. The present sensor for heparin detection possessed a low detection limit and wide linear range. Additionally, the proposed method was also applied to the detection of heparin in biological media with satisfactory results.
研究领域:
纳米技术
·
分析化学
·
生物传感器
✓ 已验证
DOI
PubMed
高影响因子
MOLECULAR BIOTECHNOLOGY
·
2021
·Vol. 63
·期 6
·491-501
·
IF 2.695
Tang Wanggang,Lian Chaoqun,Si Yu,Chang Jianrong
2,3-Butanediol dehydrogenase (BDH), also known as acetoin/diacetyl reductase, is a pivotal enzyme for the formation of 2,3-butanediol (2,3-BD), a chiral compound with potential roles in the virulence of certain pathogens. Here, a NAD(H)-dependent (2 R ,3 R )-BDH from Neisseria gonorrhoeae FA1090 (NgBDH), the causative agent of gonorrhoea, was functionally characterized. Sequence analysis indicated that it belongs to zinc-containing medium-chain dehydrogenase/reductase family. The recombinant NgBDH migrated as a single band with a size of around 45 kDa on SDS-PAGE and could be confirmed by Western blotting and mass spectrometry. For the oxidation of either (2 R ,3 R )-2,3-BD or meso -2,3-BD, the enzyme exhibited a broad pH optimum between pH 9.5 to 11.5. For the reduction of (3 R /3 S )-acetoin, the pH optimum was around 6.5. The enzyme could catalyze the stereospecific oxidation of (2 R ,3 R )-2,3-BD ( K m = 0.16 mM, k cat / K m = 673 s −1 · mM −1 ) and meso -BD ( K m = 0.72 mM, k cat / K m = 165 s −1 · mM −1 ). Moreover, it could also reduce (3 R /3 S )-acetoin with a K m of 0.14 mM and a k cat / K m of 885 s −1 · mM −1 . The results presented here contribute to understand the 2,3-BD metabolism in N. gonorrhoeae and pave the way for studying the influence of 2,3-BD metabolism on the virulence of this pathogen in the future.
研究领域:
微生物学
·
生物化学
✓ 已验证
DOI
PubMed
高影响因子
Journal of Analysis and Testing
·
2022
·Vol. 6
·期 1
·12-19
·
IF 0
Wang Xin-Yan,Li Yuanfang,Lv Shuzhen,Bi Sai
Herein, a dual-signal electrochemical biosensor has been developed by self-assembly of pH-activatable i-motif probes on magnetic microparticles (MMPs) coupled with DNA walker for signal amplification. In this study, the cytosine (C)-rich single-stranded DNAs are hybridized with DNA initiators to obtain the long-nicked duplexes with repeated units, which are further captured on MMPs to form the magnetic i-motif containers. The resulting duplexes contain abundant G–C base pairs, thus providing extensive binding sites for doxorubicin (DOX). At acidic pH, the C-rich sequences are folded into i-motif structure, resulting in the release of DOX and walker initiators. In this case, the liberated DOX is adsorbed on graphene quantum dots-modified glassy carbon electrode via π–π interaction, while the walker initiators as a moving part can catalyze the hybridization between MB-modified fueler DNA and tracker DNA on electrode, contributing to the generation of dual electrochemical signals induced by MB and DOX. Importantly, the magnetic separation can effectively reduce the background, achieving sensitive biosensing of pH ranging from 4.0 to 7.4 with excellent stability. Moreover, the proposed dual-signal electrochemical biosensor has been successfully applied for accurate monitoring of pH in human serum, which holds great potential in pH-dependent bioassays, especially in ultra-micro analysis for clinical applications.
研究领域:
生物化学
·
分析化学
·
医学诊断
✓ 已验证
DOI
BIOTECHNOLOGY LETTERS
·
2022
·Vol. 44
·期 4
·623-633
·
IF 2.716
Hao Zhi-kui,Li Jian-song,Wang Dan-hua,He Fei,Xue Jing-shi,Yin Liang-hong,Zheng Hua-bao
Objectives Shellfish waste is a primary source for making N -acetyl- d -glucosamine. Thus, establishing a high-efficiency and low-cost bioconversion method to produce N -acetyl- d -glucosamine directly from shellfish waste was promising.
Results A mutant C81 was obtained from Chitinolyticbacter meiyuanensis SYBC-H1 via 60 Co-γ irradiation. This mutant C81 showed the highest chitinase activity of 9.8 U/mL that was 85% higher than the parent strain. The mutant C81 exhibted improved antioxidant activities, including total antioxidant capacity, superoxide radical ability, and hydroxyl radical scavenging ability, compared to that of the parent strain. Four out of nine organic solvents increased the chitinase activity by 1.9%, 6.8%, 11.7%, and 15.8%, corresponding to methylbenzene, n-heptane, petroleum ether, and n-hexane, respectively. The biphase system composed of aqueous and hexane presented a five-fold reduction of cell viability compared to the control. Using a continuous fermentation bioconversion process, 4.2 g/L GlcNAc was produced from crayfish shell powder with a yield of 80% of the chitin content. Conclusions This study demonstrated that the mutant C81 is suitable for converting crayfish shell powder into GlcNAc in an aqueous-organic system.
研究领域:
微生物学
·
生物化学
·
生物工程
✓ 已验证
DOI
PubMed
高影响因子
Nature Communications
·
2020
·Vol. 11
·期 1
·1-9
·
IF 12.121
Wang Lingxiang,Guan Erjia,Wang Yeqing,Wang Liang,Gong Zhongmiao,Cui Yi,Meng Xiangju,Gates Bruce C.,Xiao Feng-Shou
The reaction pathways on supported catalysts can be tuned by optimizing the catalyst structures, which helps the development of efficient catalysts. Such design is particularly desired for CO 2 hydrogenation, which is characterized by complex pathways and multiple products. Here, we report an investigation of supported cobalt, which is known for its hydrocarbon production and ability to turn into a selective catalyst for methanol synthesis in CO 2 hydrogenation which exhibits good activity and stability. The crucial technique is to use the silica, acting as a support and ligand, to modify the cobalt species via Co‒O‒SiO n linkages, which favor the reactivity of spectroscopically identified *CH 3 O intermediates, that more readily undergo hydrogenation to methanol than the C‒O dissociation associated with hydrocarbon formation. Cobalt catalysts in this class offer appealing opportunities for optimizing selectivity in CO 2 hydrogenation and producing high-grade methanol. By identifying this function of silica, we provide support for rationally controlling these reaction pathways.
研究领域:
催化
·
化学工程
·
材料科学
·
环境化学
✓ 已验证
DOI
PubMed
高影响因子
Frontiers of Chemical Science and Engineering
·
2023
·Vol. 17
·期 7
·906-917
·
IF 4.5
Zou Min,Tan Chao,Yuan Zhengqiu,Wu Ming,Jian Jian,Zhang Lei,Zhang Yan,Ma Zhou,Zhou Hu
The industrial application of nano-photocatalysts in wastewater treatment has been severely restricted for a long time due to their difficult separation, poor reusability, and low efficiency. In this work, a facile strategy was proposed to enhance the photocatalytic activity and recovery performance of Ag@AgCl nanocatalysts. Biological veins (Bio-veins) with a unique 3D porous construction were used as carriers for the in-situ growth of Ag@AgCl nanoparticles. Scanning electron microscopy results showed that the Ag@AgCl nanoparticles were uniformly loaded on the surface and interior of the Bio-veins, and the size of the Ag@AgCl nanoparticles immobilized on the Bio-veins (50–300 nm) was significantly smaller than Ag@AgCl obtained by the co-precipitation method (1–3 µm). The Bio-veins played a vital role in the photocatalysis reaction system. The degradation efficiency of the Ag@AgCl/Bio-veins(CI4) was up to 3.50 times as high as pure Ag@AgCl. Furthermore, the composites also exhibited excellent recyclability and stability under both visible and solar light. This work provided a suitable strategy for nanophotocatalysts for practical application and may also offer new possibilities for the high-value utilization of biomass materials.
研究领域:
环境科学
·
材料科学
·
生物学
✓ 已验证
DOI
高影响因子
JOURNAL OF POROUS MATERIALS
·
2019
·Vol. 27
·期 1
·11-19
·
IF 1.947
Fu Hong Yi,Lu Cheng,Huang Yu Hui,Li Juan,Wu Yong Jun
Porous texture of graphene-hydrogel electrode material is critical for the performance of supercapacitors. In this work, the pore channels are controlled by two aspects, including the graphene oxide concentration and the pressure for fabricating hydrogel electrodes. It is found that the sample starting from 3 mg ml −1 graphene oxide shows the largest specific capacitance of 297 F g −1 at a current density of 0.5 A g −1 in 2 M KOH solution after the hydrothermal process. By increasing the pressure to 10 MPa, the electrochemical performance can be further improved to 330 F g −1 . This good performance is mainly attributed to the preferable specific surface area (2110 m 2 g −1 ) and the dense laminated structure under the optimizing preparation conditions. Besides, the cycle measurement demonstrates the excellent cycling stability of the samples, while 88% of its initial capacitance can be retained after 10,000 cycles.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）