ANALYTICAL CHEMISTRY
·
2014
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IF 5.825
Zong-Mian Zhang,Jing-Fu Liu,Rui Liu,Jie-Fang Sun,Guo-Hua Wei
By coupling surface-enhanced Raman spectroscopy (SERS) with thin layer chromatography (TLC), a facile and powerful method was developed for on-site monitoring the process of chemical reactions. Samples were preseparated on a TLC plate following a common TLC procedure, and then determined by SERS after fabricating a large-area, uniform SERS substrate on the TLC plate by spraying gold nanoparticles (AuNPs). Reproducible and strong SERS signals were obtained with substrates prepared by spraying 42-nm AuNPs at a density of 5.54 × 1010 N/cm2 on the TLC plate. The capacity of this TLC-SERS method was evaluated by monitoring a typical Suzuki coupling reaction of phenylboronic acid and 2-bromopyridine as a model. Results showed that this proposed method is able to identify reaction product that is invisible to the naked eye, and distinguish the reactant 2-bromopyridine and product 2-phenylpyridine, which showed almost the same retention factors (Rf). Under the optimized conditions, the peak area of the characteristic Raman band (755 cm–1) of the product 2-phenylpyridine showed a good linear correlation with concentration in the range of 2–200 mg/L (R2 = 0.9741), the estimated detection limit (1 mg/L 2-phenylpyridine) is much lower than the concentration of the chemicals in the common organic synthesis reaction system, and the product yield determined by the proposed TLC-SERS method agreed very well with that by UPLC-MS/MS. In addition, a new byproduct in the reaction system was found and identified through continuous Raman detection from the point of sample to the solvent front. This facile TLC-SERS method is quick, easy to handle, low-cost, sensitive, and can be exploited in on-site monitoring the processes of chemical reactions, as well as environmental and biological processes.
研究领域:
分析化学
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材料科学
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化工
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环境科学
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生物技术
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高影响因子
DALTON TRANSACTIONS
·
2024
·Vol. 53
·期 11
·5284-5290
·
IF 3.5
Weiyu Qu,Xinrui Yang,Xiaojin Huang,Weiliang Guo,Zhihui Dai
Herein we report electrochemiluminescence (ECL) generation from three new iridium(III)/ruthenium(II) (Ir(III)/Ru(II)) complexes with naphthyl (nap) tags in solutions and host–guest thin films. In comparison with its parent structure, the addition of a nap tag to [4-(2-naphthalenyl)-1,10-phenanthroline]bis(2,2′-bipyridine)ruthenium(II) results in a 6.1-fold enhancement in the ECL efficiency. Moreover, the nap tag enables the non-covalent immobilization of Ir(III)/Ru(II) complexes via host–guest interactions. Therefore, a molecular thin film was constructed by hydrophobic effects between the cavity of β-cyclodextrin and the nap tags, which emits stable and strong ECL emission in the presence of tri-n-propylamine (TPrA). These results give a mechanistic insight into ECL generation from (Ir(III)/Ru(II)) complexes with host–guest recognition tags and may help in the development of host–guest thin film-based ECL sensors.
研究领域:
分析化学
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材料科学
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PubMed
高影响因子
ANALYTICAL AND BIOANALYTICAL CHEMISTRY
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2025
·
IF 3.8
Xu Heng-Yu,Jiang Zhi-Cai,Lu Cheng-Fei,Li Mao-Song,Chen Zhao-Ding,Liu Li-Lan,Xu Shu-Ting,Liu Bo,Hu Jun
Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous toxic pollutants that pose significant risks to human health. However, because of their intrinsic non-polar properties, only moderate detection sensitivity can be achieved in the mass spectrometric detection of PAHs. In this work, we presented a novel electrochemically assisted derivatization nano-electrospray ionization mass spectrometry (ECAD-nESI-MS) method to permit the rapid and ultrasensitive analysis of PAHs in complicated samples. In ECAD-nESI-MS, the in situ electrochemical derivatization of PAHs with pyridine and the electrospray ionization are simultaneously activated by applying a high voltage onto the Pt electrode. Notably, the derivatization takes advantage of the inherent electrochemical aspect of electrospray ionization, that is, the electrooxidation of substrates in the positive-ion mode, thus requiring no extra electrochemical cell and potentiostat. Through the electrochemical derivatization of PAHs into the corresponding pyridinium ions, the ECAD-nESI-MS method achieved remarkably improved detection sensitivity, where the limit of detection (LOD) is 3~10 times lower than the state-of-the-art atmospheric pressure chemical ionization mass spectrometry (APCI-MS) and gas chromatography mass spectrometry (GC-MS). With advantages in low detection limit, wide linear range, fast analysis speed (< 3 min per sample), and low sample consumption, we anticipate the wide application of the ECAD-nESI-MS method in the rapid and sensitive analysis of PAHs and their analogues. Graphical abstract
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高影响因子
ANALYTICAL CHEMISTRY
·
2015
·
IF 5.636
Chunxiang Li,Hongyang Wang,Jing Shen,Bo Tang
Photoactive material is the most crucial factor which intimately determines analytical performances of the photoelectrochemical sensor. On the basis of the high affinity of dipyrido [3,2-a:2′,3′-c] phenazine (dppz) with DNA helix, a novel photoactive intercalator, [(ppy)2Ir(dppz)]+PF6–(ppy = 2-phenylpyridine and dppz = dipyrido [3,2-a:2′,3′-c] phenazine) was prepared and characterized by UV–vis absorption spectroscopy, fluorescence spectroscopy, and cyclic voltammetry. The photoelectrochemical properties of the as-prepared iridium(III) complex immobilized on the ITO electrode was investigated. Either cathodic or anodic photocurrent generation can be observed when triethanolamine (TEOA) or dissolved O2 is used as a sacrificial electron donor/acceptor, respectively. The probable photocurrent-generation mechanisms are speculated. A highly sensitive iridium(III) complex-based photoelectrochemical sensor was proposed for DNA detection via hybridization chain reaction (HCR) signal amplification. Under optimal conditions, the biosensor was found to be linearly proportional to the logarithm of target DNA concentration in the range from 0.025 to 100 pmol L–1 with a detection limit of 9.0 fmol L–1 (3σ). Moreover, the proposed sensor displayed high selectivity and good reproducibility, demonstrating efficient and stable photoelectric conversion ability of the Ir(III) complex.
研究领域:
生物化学
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分析化学
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材料科学
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高影响因子
Journal of the American Chemical Society
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2018
·
IF 14.357
Weiliang Guo,Hao Ding,Chaoyue Gu,Yanhuan Liu,Xuecheng Jiang,Bin Su,Yuanhua Shao
Electrochemiluminescence (ECL) is a highly successful technique used in commercial immunoassays for clinical diagnosis. Developing an ECL-based multiplex immunoassay, with the potential to enable high-throughput detection of multiple biomarkers simultaneously, remains a current research interest yet is limited by a narrow choice of ECL luminophores. Herein we report the synthesis, photophysics, electrochemistry, and ECL of several new ruthenium(II) and iridium(III) complexes, three of which are eventually used as signal reporters for multiplex immunoassay. The ECL behaviors of individual luminophores and their mixtures were investigated in multiple modes, including light intensity, spectrum, and image measurements. The spectral peak separation between Ru(bpy)2(dvbpy)2+ (bpy = 2,2′-bipyridine, dvbpy = 4,4′-bis(4-vinylphenyl)-2,2′-bipyridine), and Ir(dFCF3ppy)2(dtbbpy)+ (dFCF3ppy = 3,5-difluoro-2-[5-(trifluoromethyl)-2-pyridinyl]phenyl, dtbbpy = 4,4′-bis(tert-butyl)-2,2′-bipyridine) was up to 145 nm, thus providing the spectrum-resolved possibility of identifying light signals. The potential-resolved ECL signals were achieved for the mixtures of Ir(ppy)3 (ppy = 2-phenylpyridine) with either Ru(bpy)2(dvbpy)2+ or Ir(dFCF3ppy)2(dtbbpy)+, due to the self-annihilation ECL of Ir(ppy)3 at higher potentials, as confirmed by electrochemistry-coupled mass spectrometry. A multiplex immunoassay free of spatial spotting antibodies on plates or substrates was ultimately devised by combining luminophore-loaded polymer beads with the homogeneous sandwich immunoreaction. Using potential and spectrum dual-resolved ECL as the readout signal, simultaneous recognition of three antigens, namely, carcinoembryonic antigen (CEA), alpha-fetoprotein (AFP), and beta-human chorionic gonadotropin (β-HCG), was demonstrated in a single run for a sample volume of 300 μL. These results contribute to the understanding of ECL generation by multiple luminophores and devising spot-free multiplex immunoassays with less sample consumption.
研究领域:
分析化学
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生物医学工程
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临床诊断
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PubMed
高影响因子
Biomimetics
·
2022
·Vol. 7
·期 4
·237
·
IF 3.743
Minglei Gong,Wei Li,Fei Fan,Yu Chen,Bin Zhang
The development of organic memory devices, regarding factors such as structure construction, principle exploration, and material design, has become a powerful supplement to traditional silicon-based information storage. The in-situ growth of materials on substrate surfaces can achieve closer bonding between materials and electrodes. Bio-inspired by mussel chemistry, polydopamine (PDA) was self-assembled on a flexible substrate as a connecting layer, and 2-bromoiso-butyryl bromide (BiBB) was utilized as an initiator for the polymerization of an iridium complex via surface-initiated atom-transfer radical polymerization (SI-ATRP). A device with the structure of Al/PDA-PPy3Ir/ITO was constructed after the deposition of aluminum. The device exhibited a nonvolatile rewritable memory characteristic with a turn-on voltage of −1.0 V and an ON/OFF current ratio of 6.3 × 103. In addition, the memory performance of the Al/PDA-PPy3Ir/ITO device remained stable at bending states due to the intrinsic flexibility of the active layer, which can be expanded into the establishment of flexible memory devices. Spectroscopy and electrochemical characterization suggested that the resistive memory properties of the device stemmed from charge transfer between PDA and iridium polymer in the active layer (PDA-PPy3Ir) under an applied voltage.Keywords:memory device;mussel chemistry;surface modification;SI-ATRP
研究领域:
材料科学
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电子学
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高分子化学
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高影响因子
JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY
·
2022
·
IF 3.262
Qiuyu Lin,Luyun Xue,Jiannan Sun,Yuanchao Wang,Heyong Cheng
Suzuki–Miyaura cross-coupling is one of the most powerful strategies for constructing biaryl compounds. However, classic Suzuki–Miyaura coupling suffers from hour-scale reaction time and competitive protodeboronation. To address these problems, a mild nonaqueous potassium trimethylsilanolate (TMSOK)-assisted Suzuki–Miyaura coupling strategy was designed for the microsynthesis of biaryls in paper spray ionization (PSI). Due to the acceleration power facilitated by microdroplet chemistry in reactive PSI, the microsynthesis of biaryls by reactive PSI was accomplished within minutes with comparable yields to the bulk, showing good substrate applicability from 32 Suzuki–Miyaura reactions of aryl bromides and aryl boronic acid/borates bearing different substituents. Based on the above TMSOK-assisted Suzuki–Miyaura coupling strategy, we further developed a high-sensitivity and selective PSI mass spectrometry (MS) method for quantitative analysis of aryl bromides, a class of environmentally persistent organic pollutants that cannot be directly detected by ambient mass spectrometry due to their low ionization efficiency. In situ derivatization of aryl bromides was achieved with aryl borates bearing quaternary ammonium groups in PSI. The proposed PSI-MS method shows good linearity over the 0.01–10 μmol L–1 range with low detection limits of 1.8–4.8 nmol L–1 as well as good applicability to the rapid determination of six aryl bromides in three environmental water samples. The proposed PSI-MS method also shows good applicability to brominated flame retardants (polybrominated diphenyls/diphenyl esters). Overall, this study provides a simple, rapid, low-cost, high-sensitivity, and high-selectivity strategy for trace aryl bromides and other brominated pollutants in real samples with minimal/no sample pretreatment.
研究领域:
分析化学
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环境科学
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有机化学
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高影响因子
ACS Sustainable Chemistry & Engineering
·
2023
·
IF 8.4
Shuang Chen,Yue Wang,Yifan Huang,Yifan Zhang,Pengyang Deng
A novel photosensitizer hybrid film (Ir(cumr)2(dabpy)+@NWF-g-MAH) has been designed and synthesized by anchoring a coumarin–Ir(III) complex on a polymer substrate. Photocatalytic tests show that Ir(cumr)2(dabpy)+@NWF-g-MAH displays a long lifetime of over 650 h under visible-light irradiation. The hydrogen evolution efficiency of Ir(cumr)2(dabpy)+@NWF-g-MAH is nearly 25 times higher than that of [Ir(ppy)2(dabpy)]+@NWF-g-MAH in 100 h, and optimizing the average concentration of Ir(cumr)2(dabpy)+@NWF-g-MAH in the hydrogen evolution system improves the hydrogen evolution amount to 12 790 μmol m–2. This photocatalytic system achieves the best synergy of hydrogen evolution efficiency and lifetime so far. The high performance is derived from the sterically bulky substrate effectively inhibiting the photodegradation of the photosensitizer and the coumarin group with strong visible-light absorption in the visible region. This work provides a novel direction for developing a durable and efficient Ir(III) complex for photocatalytic application.
研究领域:
材料科学
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光催化
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能源材料
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化学工程
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DOI
高影响因子
ANALYTICAL CHEMISTRY
·
2023
·
IF 7.4
Xinrui Yang,Yingying Xu,Xiaojin Huang,Junmeng Hang,Weiliang Guo,Zhihui Dai
Cyclometalated Ir(III) complexes with high electrochemiluminescence (ECL) efficiency and appropriate bioconjugation sites are urgently needed in ECL immunoassays (ECLIA). Herein, we report the synthesis, photophysics, electrochemistry, and ECL of six new Ir(III) complexes bearing naphthyl (nap) or adamantane phenyl (adap) substitutions, four of which emit cyan, green, or red light and display 1.7- to 7.5-fold increases in ECL intensity. In combination with DFT/TDDFT calculations, this enhancement is rationalized to the augmented radiative rate that arises from both the strengthened spin-orbit coupling (SOC) and the increased transition dipole moment. In addition, the adap-based Ir(III) complex shows high binding affinity with β-cyclodextrin (β-CD) due to the strong hydrophobic interaction, which enables us to develop a modular strategy for the labeling of Ir(III) complexes with biomolecules and to use hydrophobic luminophores in the aqueous-phase detection. As demonstrated, a novel ECLIA is built up and exhibits a wide linear range from 1 ng/mL to 10 μg/mL and a detection limit of 72 pg/mL for the determination of C-reactive protein (CRP). These findings provide new insights into the design, synthesis, and bio-labeling of highly emissive Ir(III) complexes and pave the way for the development of novel ECLIA based on host–guest recognition motifs.
研究领域:
分析化学
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材料科学
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生物化学
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纳米技术
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高影响因子
ChemSusChem
·
2023
·
IF 8.4
Pu Zhang,Haihua Zeng,Decai Wen,Xiaoyu Sui,Zhuan Wang,Ying Wang,Hailong Chen,Yuxiang Weng,Jinlin Long
Graphical With the combination of surface organometallic chemistry and post-synthetic ligand exchange or calcination, the coordination environments of Ni sites were precisely manipulated to achieve a splendid improvement in hydrogen evolution reaction (HER) under visible-light irradiation. Thereinto, the 2,2′-bipyridine bonded Ni catalyst showed the optimum HER ability, 260 folds as Ni without ligand and 2.5 folds as 2-phenylpyridine bonded Ni catalyst. Solar hydrogen production at a high efficiency holds the significant importance in the age of energy crisis, while the micro-environment manipulation of active sites on photocatalysts plays a profound role in enhancing the catalytic performance. In this work, a series of well-defined single-site Ni-grafted TiO 2 photocatalysts with unique and specific coordination environments, 2,2′-bipyridine-Ni−O−TiO 2 (T−Ni Bpy) and 2-Phenylpyridine-Ni−O−TiO 2 (T−Ni Phpy), were constructed with the methods of surface organometallic chemistry combined with surface ligand exchange for visible-light-induced photocatalytic hydrogen evolution reaction (HER). A prominent rate of 33.82 μmol ⋅ g −1 ⋅ h −1 and a turnover frequency of 0.451 h −1 for Ni are achieved over the optimal catalyst T−Ni Bpy for HER, 260-fold higher than those of Ni−O−TiO 2 . Fewer electrons trapped oxygen vacancies and a larger portion of long-lived photogenerated electrons (>3 ns, ~52.9 %), which were demonstrated by the electron paramagnetic resonance and femtosecond transient IR absorption, correspond to the photocatalytic HER activity over the T−Ni Bpy. The number of long-lived free electrons injected from the Ni photoabsorber to the conduction band of TiO 2 is one of the determining factors for achieving the excellent HER activity.
研究领域:
材料科学
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催化化学
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能源科学
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PubMed
高影响因子
ANALYTICAL LETTERS
·
2023
·
IF 2
Jiawei Li,Cailin Qiao,Huan Liu,Dong Zhao,Jing Zhang,Laichun Lu,Danqun Huo,Changjun Hou
The discrimination and determination of small organics may be employed for baijiu identification. A single nanoparticle was designed as a fluorescence sensor to address this issue. Via specific host-guest interactions, small organics may significantly disrupt the energy transmission of nanoparticles, resulting in sharp changes in characteristic fluorescence peaks, thus allowing the discrimination of single substances or mixtures by principal component analysis (PCA), hierarchical clustering analysis (HCA), and linear discriminant analysis (LDA). The system was characterized by transmission electron microscopy with energy dispersive spectrometry and fluorescence spectroscopy. 15 small flavor organics in baijiu were successfully discriminated. Moreover, the linear relationship between the concentrations of tryptophan and ethyl butyrate with the corresponding responsiveness demonstrated the capabilities of the sensor. The reported device was successfully applied to distinguish 16 baijiu brands. This simple and rapid method has outstanding potential for the characterization of alcoholic beverages.
研究领域:
分析化学
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食品科学
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纳米技术
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DOI
高影响因子
危险品化学品经营许可证（带存储）