SENSORS AND ACTUATORS B-CHEMICAL
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2019
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IF 6.393
Jiahao Wu,Chao Yu,Yujie Yu,Jun Chen,Chengli Zhang,Rufei Gao,Xinyi Mu,Yanqing Geng,Junlin He
A novel dual-mode aptasensor was fabricated for ultra-sensitive detection of microcystin-LR (MC-LR). The direct method was developed using chronoamperometry for quick detection. A glass carbon electrode (GCE) was first modified with MoS 2 -PtPd nanoparticles (NPs). MoS 2 -PtPd was used as a substrate for a higher loading of aptamers and to amplify the signal by catalytic activity toward H 2 O 2 . The aptamer was then assembled onto the modified electrode surface to work as a recognition probe to bind MC-LR. To increase the sensitivity of the aptasensor, we developed an indirect method for ultra-sensitive detection through synthesizing and utilizing novel zeolitic imidazolate framework (ZIF)-8-thionine (Thi)-Au as signal material for the first time. This signal material not only possessed the high conductivity of Au NPs, but also produced current signal from a redox reaction by Thi . The complementary strand of the aptamer was immobilized on the surface of ZIF-8-Thi-Au and their compounds hybridized with the aptamer on the MoS 2 -PtPd modified GCE. MC-LR would replace ZIF-8-Thi-Au compounds by competition binding with the aptamer. The electrical signal would decrease then and be detected by SWV. Under optimal conditions, the linear ranges of the indirect and direct methods were respectively 0.01–50 and 0.1–50 ng mL −1 . And LOD of the indirect and direct method were respectively 0.006 and 0.045 ng mL −1 (signal-to-noise ratio = 3). The aptasensor ensured the accuracy of the detection outcome through comparing the results of the two modes and provided a potentially reliable and ultra-sensitive detection method of MC-LR in water environments.
研究领域:
分析化学
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环境科学
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纳米技术
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电化学
✓ 已验证
产品关联
DOI
高影响因子
ELECTROCHIMICA ACTA
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2015
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IF 4.504
Jing-Jing Lv,Nattawadee Wisitruangsakul,Jiu-Ju Feng,Jun Luo,Ke-Ming Fang,Ai-Jun Wang
In this work, we have prepared porous PtPd alloyed nanoflowers uniformly supported on reduced graphene oxide by a simple and facile wet-chemical method, with the assistance of cytosine as a structure-directing agent. The products were mainly characterized by transmission electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopy. The as-prepared nanocomposites displayed improved electrocatalytic performances toward ethanol oxidation in alkaline media and oxygen reduction in acidic media, which make it a promising electrocatalyst in fuel cells.
研究领域:
材料科学
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电化学
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纳米技术
✓ 已验证
DOI
高影响因子
ACS Omega
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2019
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IF 2.584
Hua Zhang,Linlin Xu,Yue Tian,Anxin Jiao,Shuang Li,Xiangdong Liu,Ming Chen,Feng Chen
Fuel cells hold great promise for clean and sustainable energy, whereas their widespread commercialization strongly depends on the development of highly efficient and stable electrocatalysts. Herein, three-dimensional fluffy PtPd nanocorals (NCs) loaded on two-dimensional (2D) hexagonal boron nitride (h-BN) supports were successfully achieved by a simple one-step strategy based on ultraviolet (UV) laser-excited photochemical reaction. As for alcohol oxidation reaction, the h-BN/PtPd NCs with unique nanoporous surface provide more enhanced electrocatalytic performances than many previous nanocatalysts, owing to abundant active sites and plentiful charge-transfer channels formed on high electrode–electrolyte contact area. Especially, the mass activity of h-BN/PtPd NCs is about 962.8 mA mgPtPd–1 in methanol oxidation reaction in alkaline solution, which can be maintained at ∼274.9 mA mgPtPd–1 (28.6% of the initial one) even after a 5 × 104 s durability test. The present work not only offers an advanced electrocatalyst for long-term fuel cells but also provides a versatile route for construction of complex metallic nanocomposites on 2D supports, holding great potential for diverse energy-related applications.
研究领域:
材料科学
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能源科学
✓ 已验证
DOI
PubMed
高影响因子
ANALYTICA CHIMICA ACTA
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2022
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IF 6.911
Mengyang Li,Baoshan He,Haoyang Yan,Lingling Xie,Xiaoyu Cao,Huali Jin,Min Wei,Wenjie Ren,Zhiguang Suo,Yiwei Xu
A novel ultrasensitive electrochemical aptasensor was proposed for quantitative detection of Cd 2+ . To this end, flower-like polyethyleneimine-functionalized molybdenum disulfide-supported gold nanoparticles (PEI-MoS 2 [email protected] NPs) were used as substrates for the modification of bare gold electrodes (AuE). PEI-MoS 2 [email protected] NPs not only possessed excellent biocompatibility and large specific surface area to enhance the cDNA loading capacity, but also possessed good conductivity to accelerate the electron transfer rate. Furthermore, the preparation of dendritic platinum-palladium nanoparticles (PtPd NPs) can effectively load Cd 2+ -aptamer. Thionine and aptamers were loaded onto PtPd NPs to construct Thi-PtPd NPs-aptamer signal probes. The signal probes were captured by the cDNA immobilized on the electrode via base-pairing rule, and the signal of Thi was detected by differential pulse voltammetry (DPV). In the presence of Cd 2+ , aptamer-cDNA unwinded, and the combination of aptamer and Cd 2+ caused the signal probes to fall off the electrode and the electrical signal decreases. Under optimal conditions, the proposed aptasensor exhibited a linear relationship between the logarithm of Cd 2+ concentration and the current response over a wide range of 1 × 10 −3 nM to 1 × 10 2 nM, with a detection limit of 2.34 × 10 −4 nM. At the same time, the aptasensor was used to detect Cd 2+ in tap water with satisfactory results. In addition, it has good reproducibility, selectivity and stability, and has broad application prospects in heavy metal analysis.
研究领域:
分析化学
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环境科学
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纳米技术
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电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2023
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IF 13.6
Yizhong Shen,Xiang Gao,Huanhuan Chen,Yunlong Wei,Hui Yang,Ying Gu
Engineering efficient dual-mode portable sensor with built-in cross reference correction is of great significance for onsite reliable and precise detection of organophosphorus pesticides (OPs) and evading the false-positive outputs, especially in emergency case. Currently, most nanozyme-based sensors for OPs monitoring primarily replied on the peroxidase-like activity, which involved unstable and toxic H 2 O 2 . In this scenario, a hybrid oxidase-like 2D fluorescence nanozyme ( [email protected] 3 N 4 ) was yielded by in situ growing PtPdNPs in the ultrathin two-dimensional (2D) graphitic carbon nitride (g-C 3 N 4 ) nanosheet. When acetylcholinesterase (AChE) hydrolyzed acetylthiocholine (ATCh) to thiocholine (TCh), it ablated O 2 − • from the dissolved O 2 catalyzed by [email protected] 3 N 4 ’s oxidase-like activity, hampering the oxidation of o-phenylenediamine (OPD) into 2,3-diaminophenothiazine (DAP). Consequently, with the increasing concentration of OPs which inhibited the blocking effect by inactivating AChE, the produced DAP caused an apparent color change and a dual-color ratiometric fluorescence change in the response system. Through integrating into a smartphone, a H 2 O 2 -free 2D nanozyme-based onsite colorimetric and fluorescence dual-mode visual imaging sensor for OPs was proposed with acceptable results in real samples, which holds vast promise for further development of commercial point-of-care testing platform in early warning and controlling of OPs pollution for safeguarding environmental health and food safety.
研究领域:
材料科学
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分析化学
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环境科学
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生物技术
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纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MICROCHEMICAL JOURNAL
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2024
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IF 4.9
Qi Xiao,Jiawen Li,Shuai Liu,Mingli Yang,Yi Fang,Shan Huang
Given the pivotal role of hydrogen peroxide (H 2 O 2 ) in numerous biological progresses, there has been a recent surge in the development of highly effective electrochemical sensors for H 2 O 2 detection. In this article, we propose an enzyme-free amperometric system for the sensitive and selective recognition of H 2 O 2 , leveraging ultrafine PtPd alloy/ionic liquid-carbon dots (IL-CDs) nanocomposites modified flexible carbon fiber. The IL-CDs were synthesized through the direct electrodeposition of ionic liquid [BMIM][PF 6 ] using Pt sheets as electrodes. Subsequently, a sequential electrodeposition of IL-CDs, H 2 PtCl 6 , and PdCl 2 onto the activated carbon fiber (ACF) yielded the PtPd/IL-CDs/ACF microelectrode. This microelectrode serves as an enzyme-free amperometric sensor for H 2 O 2 detection, exhibiting an improved response with a significantly lower detection limit of 0.29 μM and a relatively broad linear range spanning from 2 to 6561 μM. Furthermore, this enzyme-free amperometric H 2 O 2 sensor demonstrates remarkable stability over extended periods and exceptional performance in practical applications, such as the analysis of commercially available milk, human serum, human urine, and living cancer cells analysis. This study offers a fresh perspective on amperometric sensors based on metal alloys and CDs electrode, highlighting the potential of enzyme-independent detection for hydrogen peroxide in biological systems.
研究领域:
生物医学工程
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分析化学
✓ 已验证
产品关联
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
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2020
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IF 7.1
Hui Liu,Jinshui Wang,Huali Jin,Min Wei,Wenjie Ren,Yurong Zhang,Ligen Wu,Baoshan He
A sensitive electrochemical biosensor was constructed for Hg 2+ detection based on peonylike Cu-MOFs in situ growth of PtPd NPs bimetallic label S 1 and Mg 2+ -dependent DNAzyme-driven DNA Walker dual amplification signal strategy. The hairpin DNA (HP) and signal label [email protected] NPs/S 1 were first used to self-assemble on the gold nanorods/poly (diallyldimethylammonium chloride) functionalized graphene (AuNRs/PDDA-Gr) modified electrode, at this time, Cu ions can undergo a valence change to produce a larger initial signal. Here, we designed S 2 that can perform dual functions and contains two sequences, on was a substrate sequence of the Mg 2+ -dependent DNAzyme and the other was a sequence complementary to HP. In the presence of target Hg 2+ , HP was opened and hybridized with enzymatically sequenced DNA Walker (S 2 ) to preferentially form thymine-Hg 2+ -thymine (T-Hg 2+ -T). Then, DNA Walker exhibited catalytic activity of DNAzyme in the presence of Mg 2+ to continuously cleave [email protected] NPs/S 1 , resulting in a decrease of electrochemical signal. Under optimal conditions, the change of current was linearly related to the negative logarithm of the Hg 2+ concentration in the detection range of 0.001–100 nM with a low detection limit of 0.52 pM. Moreover, the proposed aptasensor was successfully applied in detection of milk powder samples.
研究领域:
分析化学
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环境科学
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生物化学
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纳米技术
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食品安全
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）