ANALYTICAL AND BIOANALYTICAL CHEMISTRY
·
2022
·Vol. 414
·期 13
·3755-3763
·
IF 4.478
Wu Shujie,Wang Songen,Li Zongbing,Wu Chun,Ma Dik-Lung,Miao Xiangmin
In this work, we synthesized an iridium(III) complex and studied its selective ability to interact with a specific G-quadruplex DNA sequence (GTGGGTAGGGCGGGTTGG). Results showed that the iridium(III) complex exhibits high selectivity for the G-quadruplex DNA and could be used as an efficient electrochemiluminescence (ECL) probe in a switch-on assay format for the detection of double-stranded DNA (dsDNA). To construct the assay, a hairpin-structured capture probe (CP) which was modified by thiol at its 3′ end and contained the G-quadruplex sequence at its 5′ end was firstly immobilized on a gold electrode. Upon the specific recognition of the dsDNA sequence with the corresponding CP, the hairpin structure of the CP was opened to free G-quadruplex sequence, forming the G-quadruplex structure with the assistance of K + . Then, the iridium(III) complex was able to specifically interact with the G-quadruplex to produce an obvious ECL signal that was proportional to the dsDNA concentration. Notably, this iridium(III) complex/G-quadruplex-based strategy was universal and was not limited to the analysis of DNA using specific sequences, thus opening a new avenue for the application of the G-quadruplex-selective iridium(III) complex in the field of ECL.
研究领域:
生物化学
·
分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MOLECULES
·
2022
·Vol. 27
·期 13
·4099
·
IF 4.927
Dianwei Zhang,Furui Zhang,Yonghong Liao,Fenghuan Wang,Huilin Liu
This study designed a “turn-off–on” fluorescence analysis method based on carbon quantum dots (CQDs) to detect metal ions and amino acids in real sample systems. CQDs were derived from green pomelo peel via a one-step hydrothermal process. The co-doped CQDs with N and S atoms imparted excellent optical properties (quantum yield = 17.31%). The prepared CQDs could be used as fluorescent “turn-off” probes to detect Fe3+with a limit of detection of 0.086 µM, a linear detection range of 0.1–160 µM, and recovery of 83.47–106.53% in water samples. The quenched CQD fluorescence could be turned on after adding L-cysteine (L-Cys), which allowed detection of L-Cys with a detection limit of 0.34 µM and linear range of 0.4–85 µM. Recovery of L-Cys in amino acid beverage was 87.08–122.74%. Visual paper-based testing strips and cellulose/CQDs composite hydrogels could be also used to detect Fe3+and L-Cys.Keywords:carbon quantum dots;turn-off–on;pomelo peel;fluorescence probe;Fe3+;L-cysteine
研究领域:
分析化学
·
环境科学
·
生物医学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ANALYTICAL AND BIOANALYTICAL CHEMISTRY
·
2019
·Vol. 411
·期 25
·6645-6653
·
IF 3.286
Ma Xin,Lin Shijun,Dang Yunfei,Dai Yu,Zhang Xiaojin,Xia Fan
Carbon dot (CD)-based fluorescent probes have been widely exploited; however, multi-component detection using CDs without tedious surface modification is always a challenging task. Here, we develop a convenient and simple CD-based “on-off-on” fluorescent probe for detection of copper(II) ion (Cu 2+ ), ascorbic acid (AA), and acid phosphatase (ACP). Cu 2+ leads to the fluorescence quenching of CDs. The limit of detection (LOD) for Cu 2+ is 2.4 μM. When AA is added into the CDs + Cu 2+ solution, Cu 2+ is reduced by AA to Cu + , causing the fluorescence recovery of CDs. The fluorescent intensity linearly correlates with the concentration of AA in the range of 100–2800 μM with LOD of 60 μM. Besides, the probe has potential application for detection of AA in real samples such as VC tablets, orange juice, and fresh orange. The probe can also indirectly detect ACP that enzymatically hydrolyzes ascorbic acid-phosphate (AAP) to produce AA. This work expands the application of CDs in the multi-component detection and provides a facile fluorescent probe for detection of AA in real samples.
Graphical abstract
研究领域:
分析化学
·
生物化学
·
材料科学
✓ 已验证
DOI
PubMed
高影响因子
Analytical Methods
·
2025
·
IF 2.6
Guang Wu,Shipeng He,Liwen Wang,Zhao Deng,Dating Tian,Na Zhou
Ascorbic acid (AA) is essential to human health, and accurate detection of AA content in food and drugs is necessary for disease monitoring. In this study, a hydrogen-bonded organic framework (HOF-TCBPA) was constructed with tris [(4-carboxyl)biphenyl] amine (H3TCBPA) as the only raw material, and Cu2+ was added for modification to develop a simple off-on fluorescence sensor (HOF-TCBPA/Cu2+) for detecting AA. Cu2+ can quench the fluorescence emission of HOF-TCBPA. However, in the presence of AA, the fluorescence emission of HOF-TCBPA is restored, resulting in an off-on response mechanism. The results indicated that the linear range for detecting AA concentration utilizing HOF-TCBPA/Cu2+ was 0.1-1.0 mmol/L, with a detection limit of 0.076 mmol/L. This work introduces a new platform for developing off-on fluorescence sensors using HOF/metal ions.
研究领域:
分析化学
·
材料科学
·
生物传感
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Micro & Nano Letters
·
2019
·Vol. 14
·期 9
·952-956
·
IF 0.975
Yining Zhu,Wang Li,Cheng Ju,Xiang Gong,Wenhao Song,Yu Zhao,Ruijun Li
A bovine serum albumin-stabilised gold nanoclusters/Cu 2+ (BSA-Au NCs/Cu 2+ ) system was constructed as a fluorescent sensor for the ‘off–on’ detection of glutathione (GSH). The fluorescence of BSA-Au NCs could be effectively quenched by Cu 2+ due to the strong affinity between BSA-Au NCs and Cu 2+ . Then, coordination of Cu 2+ to GSH enabled the recovery of the fluorescence of BSA-Au NCs. To assess the selectivity of the BSA-Au NCs/Cu 2+ for GSH, K + , Mg 2+ , Ca 2+ , glucose, cysteine, tryptophan, and phenylalanine were examined under identical conditions, and all of them did not induce noticeable responses to BSA-Au NCs/Cu 2+ except for Cys. There was a good linear dependence of fluorescence intensity on the concentration of GSH in the range of 0.4–20.0 μM with the detection limit of 0.36 μM. The proposed sensor showed excellent performance in the selective detection of GSH.
研究领域:
分析化学
·
纳米技术
·
生物传感器
✓ 已验证
产品关联
DOI
高影响因子
LANGMUIR
·
2012
·
IF 4.186
Qi Zhang,Guoqiang Yu,Wen-Jun Wang,Haomiao Yuan,Bo-Geng Li,Shiping Zhu
This work reports the development of a reversibly coagulatable and redispersible polystyrene latex system that can be triggered by N2/CO2. The coagulatability and redispersibility of the latexes were achieved by employing 0.9–5.6 wt % (N-amidino)dodecyl acrylamide (DAm), a reactive switchable surfactant, in an emulsion polymerization of styrene under CO2 atmosphere. The resulted latex particles were readily coagulated by N2 bubbling at 60 °C and redispersed by CO2 bubbling and ultrasonication, which switched amidine moieties between neutral and ionic states. The coagulation/redispersion processes were repeatable. The prepared latexes showed good stabilities against electrolytes, especially with higher charges.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MICROCHIMICA ACTA
·
2019
·Vol. 186
·期 6
·1-9
·
IF 5.479
Pang Jiawei,Lu Yuexiang,Gao Xinyu,He Liuying,Sun Jingwei,Yang Fengyi,Hao Zixuan,Liu Yueying
A selective fluorescent on-off-on probe has have designed for the detection of fluoride (F − ) ions based on DNA-templated copper nanocluster (CuNCs) and by using aluminum(III) ions as a bridge. A 40-mer polythymine acts as a template for the reduction of Cu(II) to Cu(0) by ascorbic acid. This result is the formation of red fluorescent CuNCs, with excitation/emission peaks at 340/640 nm. After addition of Al 3+ ions, the fluorescence of CuNCs is quenched because the interaction of Al 3+ and DNA disturbs the formation of DNA-templated CuNCs. Fluorescence is restored on addition of fluoride to the system. This is due to the desorption of Al 3+ from the DNA and the formation of the Al(OH) 3 F − complex. This system displays a fast fluorometric response to fluoride, with high selectivity over other anions. Fluorescence increases linearly in the 2 to 150 μM F − concentration range, and the detection limit is 1.0 μM. This probe has been successfully used for the detection of F − ions in four brands of toothpaste. The method is rapid, cost-effective, selective, and does not require toxic solvents and reagents.
Schematic presentation of a method for fluorometric determination of fluoride by using DNA-templated copper nanoclusters (CuNCs) and using aluminum(III) as a bridge. The red fluorescence of the CuNCs is quenched in the presence of Al(III) ions but restored after addition of fluoride.
研究领域:
分析化学
·
纳米技术
·
荧光光谱学
·
环境分析
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHINESE JOURNAL OF ANALYTICAL CHEMISTRY
·
2022
·
IF 1.193
Guan-Ting XU,Tian-Sheng ZHAO,Kun ZHANG,Li-Zhen GUO,Yong-Qin HE,Jian-Hua HU,Yi-Jing LIAO,Xi MAI,Na LI
Iron ions (Fe 3+ ) and ascorbic acid (AA) are of great significance to living organisms. Herein, carbon dots (C-dots)-based “off-on” fluorescent probe was designed for Fe 3+ and AA analysis. In presence of Fe 3+ , the fluorescence of C-dots was immediately quenched, and the quenching mechanism was deduced to be inner filter effect (IFE). The fluorescent C-dot probe shows response to Fe 3+ in range of 10–500 µM with a limit of detection (LOD) of 0.9 µM. Interestingly, when AA was introduced to the C-dots-Fe 3+ system, the fluorescence of C-dots was significantly recovered, which could be ascribed to the oxidation-reduction reaction between Fe 3+ and AA. Based “off-on” fluorescent C-dots probe, the linear range of 5–500 µM was obtained with LOD of 0.4 µM. Moreover, the AA-induced fluorescence enhancement can be recognized by smartphone, which greatly extends the application in resource-limited areas.
研究领域:
分析化学
·
环境科学
·
生物化学
✓ 已验证
产品关联
DOI
高影响因子
ANALYTICAL CHEMISTRY
·
2016
·
IF 5.886
Yanfen Wei,Dan Cheng,Tianbing Ren,Yinhui Li,Zebing Zeng,Lin Yuan
The real-time monitoring of key biospecies in the living systems has received thrusting attention during the past decades. Specifically, fluorescent detection based on near-infrared (NIR) fluorescent probes is highly favorable for live cells, live tissues, and even animal imaging, owing to the substantial merits of the NIR window, such as minimal phototoxicity, deep penetration into tissues, and low autofluorescence background. Nevertheless, developing potent NIR fluorescent probes still poses serious challenges to the chemists because traditional NIR fluorophores are less tunable than visible-wavelength fluorophores. To address this issue, here we report a set of novel NIR hybrid fluorophores, namely, the hybrid chromenylium-cyanine fluorophore (CC-Fluor), in which both the fluorescence intensity and the emission wavelength can be easily adjusted by the conformational changes and substitution groups. Compared to known NIR fluorophores, the new CC-Fluors are substantially advantageous for NIR probe development: (1) CC-Fluors display tunable and moderate Stokes shifts and quantum yields; (2) the fluorophores are stable at physiological conditions after long-term incubation; (3) the absorption maxima of CC-Fluors coincide with the common laser spectral lines in mainstream in vivo imaging systems; (4) most importantly, CC-Fluors can be easily modified to prepare NIR probes targeting various biospecies. To fully demonstrate the practical utility of CC-Fluors, we report two innovative NIR probes, a ratiometric pH probe and a turn-on Hg2+ probe, both are successfully employed in live animal imaging. Hence, the detailed studies allow us to confirm that CC-Fluors can work as an excellent platform for developing NIR probes for the detection of species in living systems.
研究领域:
化学
·
生物学
·
生物医学工程
·
材料科学
✓ 已验证
DOI
高影响因子
Analytical Methods
·
2021
·Vol. 13
·期 36
·4090-4098
·
IF 2.896
Zhen Li,Tan Wang,Xianbao Xu,Cong Wang,Daoliang Li
A novel “on–off” fluorescent probe was synthesized for highly sensitive and ultra-trace determination of ammonia nitrogen in aquaculture water. Ammonium can react with formaldehyde and sodium hydroxide to form a ring substance (urotropine), which shows no fluorescence signal. Palmatine hydrochloride (PAL) can enter the hydrophobic cavity of cucurbit[7]uril (CB[7]), eventually forming a 1 : 1 host guest complex called PAL@CB[7] under neutral or acidic conditions, which has strong green fluorescence with the maximum excitation (λex) wavelength at 343 nm, and the maximum emission (λem) wavelength at 500 nm, while urotropine has a fluorescence quenching effect on the fluorescence enhancement system of PAL@CB[7]. Therefore, a fluorescent chemosensor based on PAL@CB[7] and the reaction of ammonia nitrogen with formaldehyde was developed. The results indicate that the linearity range and the limit of detection of the proposed method are 1–300 μg L−1 with a good correlation coefficient (r2 = 0.9966) and 1.8 × 10−2 μg L−1, respectively. Under the optimal conditions, the method was employed for the detection of ammonia nitrogen in real aquaculture water samples, revealing high selectivity and sensitivity. In the future, the combination of the “on–off” fluorescence method, a portable hardware system and intelligent algorithms will provide technology support for the design of on-line sensors for measuring ammonia nitrogen in aquaculture water.
研究领域:
分析化学
·
环境科学
·
水产养殖
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2013
·
IF 3.535
Yu Zhang,Yurong Tang,Xing Liu,Lichun Zhang,Yi Lv
At present, glutathione (GSH) is a very important biomarker in vivo. However, the sensitive and selective assay for the detection of GSH in biological matrix still keeps challenging due to the high complexity of samples. Lanthanide-doped upconverting phosphors (UCPs) which exhibit unique near-infrared (NIR) excitation nature are able to overcome interferences from complex samples. In this study, a novel probe based on the linkage of UCPs and dopamine-quinone through hydrogen bonding and electrostatic interaction has been designed for rapid, economic, sensitive and selective detection of GSH in aqueous solution and human blood serum . Here, dopamine-quinone served as an efficient quencher for upconverting fluorescence, while GSH as a strong reducing agent chemically reduced the dopamine-quinone turning on the fluorescence. The fluorescence recovery was found to be proportional to GSH concentration within the range from 1 to 75 μM. The detection limit of this sensor was 0.29 μM, which was quite competitive for GSH detection. The simple, sensitive and selective fluorescence method took full advantages of UCPs properties of low interferences and broadened the application scope of UCPs in complex biological detection.
研究领域:
分析化学
·
生物分析化学
·
生物传感器
·
纳米技术
·
荧光光谱学
✓ 已验证
DOI
高影响因子
SENSORS
·
2017
·Vol. 17
·期 3
·520
·
IF 2.677
Hongyan Zhang,Zhenhong Jia
A new type of fluorescence “off-on” probe was designed for L-Cysteine (L-Cys) based on the fluorescence resonance energy transfer (FRET) between negatively charged amino-capped porous silicon nanoparticles (SiNPs) and positively charged citrate-stabilized Au nanoparticles (AuNPs). In this proposed FRET immunosensor, novel water-soluble amino-conjugated porous SiNPs in ethanol with excellent photoluminescence properties act as the energy donor. Excellent quenching efficiency between SiNPs-ethanol and citrate-stabilized AuNPs by electrostatic interaction via FRET provides an ideal “off-state” (turn-off). The addition of L-Cys leads to releasing the adsorbed AuNPs from the surface of SiNPs and hence the fluorescence emission of SiNPs-ethanol is restored (turn-on), which means the coordination ability of the thiols with AuNPs is stronger than that of the electrostatic interaction. The fluorescence intensity of SiNPs-AuNPs in ethanol is sensitive to L-Cys, and such a restored fluorescence is proportional to the concentration of L-Cys. The method will broadly benefit the development of a new thiol biosensor based on nanostructured porous materials, and the proposed procedure is also expected to develop a variety of functional nanoparticles to form other novel kinds of nanosensors.Keywords:“off-on” fluorescence biosensor;porous SiNPs;ethanol solution;AuNPs;L-Cysteine
研究领域:
纳米技术
·
分析化学
·
生物传感
✓ 已验证
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）