ANALYTICAL CHEMISTRY
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2022
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IF 8.008
Ke Min,Yong Li,Yue Lin,Xuezhi Yang,Zigu Chen,Bo Chen,Ming Ma,Qian Liu,Guibin Jiang
Soot, mainly derived from incomplete combustion of fossil fuel and biomass, exists ubiquitously in different environmental matrixes. To study the detrimental effects of soot on climate, air quality, and human health, accurate quantification of soot is an important prerequisite. However, until now, quantification of soot in environmental media, especially in carbonaceous media, is still very challenging. Here, we report a matrix-free laser desorption/ionization mass spectrometry (LDI-MS) method for in situ imaging of soot particles in size-segregated aerosol samples collected on filter membranes. A series of round-shaped sample spots in filter membranes were selected and subjected to MS imaging analysis, enabling direct in situ quantification of soot without solvent extraction or separation. Especially, the MS imaging with serial sample spots can overcome the problems of sweet-spot in LDI-MS and inhomogeneous distribution of soot in the filter membrane, thus greatly improving the precision of quantification. The limit of detection of soot was 4 ng/m2 and the recovery was 84.4–126%. By using this method, we found that a higher soot content was present in larger-sized particulate matter than smaller-sized particles, suggesting that aerosol soot was mainly derived from primary emission sources. Furthermore, this method also shows the potential to analyze nitrate and sulfate species in PM2.5. To the best of our knowledge, it is the first method capable of simultaneous analysis of inorganic salts and soot in air samples. It represents a novel strategy for in situ quantification of aerosol soot with the advantages of high specificity, high sensitivity, separation-, solvent- and matrix-free.
研究领域:
环境科学
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分析化学
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产品关联
DOI
PubMed
高影响因子
ANALYST
·
2021
·Vol. 146
·期 11
·3617-3622
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IF 4.616
Wenjie Li,Yinping Miao,Chengwei Fei,Hongmin Zhang,Bin Li,Kailiang Zhang
An enhanced photothermal signal detection method based on graphene oxide (GO) integrated long period fiber grating (LPFG) for on-site sodium copper chlorophyllin (SCC) quantification is proposed. SCC, as a porphyrin compound, can be photonically excited to induce a stronger photothermal effect. GO offers superior molecular adsorption and thermal conductivity properties; depositing it on the LPFG surface significantly improves the sensitivity and detection efficiency of the SCC photothermal signal, when irradiated with a 405 nm laser. The experimental results showed improved performance compared with those from uncoated LPFG, with a sensitivity of 0.0587 dB (mg L−1)−1 and a limit of detection (LOD) of 0.17 mg kg−1, which is also an order of magnitude lower than that of traditional high-performance liquid chromatography. The proposed method has potential applications in the fields of real-time food safety monitoring, environmental pollutant detection, and disease diagnosis.
研究领域:
光学传感
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材料科学
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食品安全
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环境监测
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生物医学诊断
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DOI
PubMed
高影响因子
RSC Advances
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2019
·Vol. 9
·期 40
·23267-23275
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IF 3.049
Jianhua Wang,Lishen Zhang,Xiaochun Li,Xiaoliang Zhang,Hua-Zhong Yu
Nowadays quantitative chemical analysis is usually costly, instrument-dependent, and time-consuming, which limits its implementation for remote locations and resource-limited regions. Inspired by the ancient papercutting art (kirigami), we herein introduce a novel cut-and-paste protocol to fabricate 3D microfluidic paper-based analytical devices (μPADs) that are suitable for on-site quantitative assay applications. The preparation of the device is fast, simple, and independent of any lithographic devices or masks. Particularly designed reaction “channels” were pre-cut from a piece of filter paper, then assembled back to the silanized, superhydrophobic paper pads. The different layers of the device were assembled using a chemically-inert adhesive spray. The fabricated device has high efficiency of liquid handling (up to 60 times faster than conventional methods) and it is particularly inexpensive. Beyond the benchtop fabrication advantage, in conjunction with a custom mobile app developed for colorimetric analysis, we were able to quantify representative environmental contaminants (i.e., the amount of Cr(VI) and nitrite ions) in various water samples with the cut-and-paste μPADs (namely kPADs). Their detection limits (0.7 μg mL−1 for Cr(VI) and 0.4 μg mL−1 for nitrite ions, respectively) are comparable with conventional spectrophotometric methods, which confirm the potential of kPADs for on-site environmental/sanitary monitoring and food toxin pre-screening.
研究领域:
分析化学
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环境科学
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生物医学工程
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DOI
PubMed
高影响因子
ACS Sensors
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2020
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IF 7.333
Meng Xiao,Zhonggang Liu,Ningxia Xu,Lelun Jiang,Mengsu Yang,Changqing Yi
The development of cost-effective and versatile sensing system for simultaneous and rapid quantitation of multiple targets is highly demanded for environmental surveillance, food safety inspection, home healthcare, etc. This work reports on (1) paper-based microarrays relying on fluorescence turn-off of carbon nanodots (CDs) for analyte recognition and (2) a stand-alone smartphone-based portable reader (SBR) installed with a custom-designed APP (SBR-App), which can accurately and reproducibly acquire fluorescence change from the microarray chip, automatically report the results, generate and share the reports via wireless network. Simultaneous detection of Hg2+, Pb2+, and Cu2+ in the Pearl River water samples was achieved with the reported sensing system. End-user operation is limited to pipet samples to the microarray chip, insert the chip to the SBR, and open the SBR-App to acquire an image 5 min after sample introduction. There is no requirement for complicated sample pre-treatment and expensive equipment except for a smartphone. This versatile and cost-effective smartphone-based sensing system featured with reliability and simplicity is ideally suited for user- and eco-friendly point-of-need detection in resource-constrained environments.
研究领域:
环境科学
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分析化学
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材料科学
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即时检测
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产品关联
DOI
PubMed
高影响因子
ANALYST
·
2019
·Vol. 144
·期 8
·2755-2764
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IF 4.019
Liyong He,Zhipeng Shen,Yuting Cao,Tianhua Li,Dazhen Wu,Youren Dong,Ning Gan
A ratiometric and sensitive microfluidic chip based aptasensor was developed for antibiotic detection with kanamycin (Kana) as a model analyte. A novel stir bar assisted sorptive extraction and rolling circle amplification strategy was designed to largely amplify the signal and overcome complex matrix interference in food samples. The detection mechanism was as follows: firstly, many duplex DNA probes (a single-stranded DNA as a primer hybrid with an aptamer sequence) were modified on a stir bar. In the presence of Kana, the probes on the bar could specifically capture Kana and release the primer to trigger RCA in the presence of a circular DNA template (CDT). As the reaction proceeds, the amount of CDT decreased and the number of RCA products increased. It is worth mentioning that they can be efficiently separated and detected using a microfluidic chip. The signal ratio of RCA products and CDT (IR/IC) can be employed to qualify Kana in a wide linear range from 0.8 pg mL−1 to 10 ng mL−1 with a low detection limit of 0.3 pg mL−1. This method exhibited excellent sensitivity and selectivity and can obviously reduce the matrix interference through a ratiometric strategy combined with stir bar extraction. The aptasensor was successfully tested in milk and fish samples, confirming that it can be applied for on-site quantitation of antibiotic residues in foods.
研究领域:
分析化学
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食品科学
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生物技术
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分子生物学
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DOI
PubMed
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
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2022
·
IF 9.221
Yun Liu,Meng Xiao,Ningxia Xu,Mengsu Yang,Changqing Yi
This study reports a new ratiometric fluorescence probe (referred to as [email protected] @bCDs) and a smartphone-based sensing system for on-site quantitation of Fe 3+ , ascorbic acid (AA), alkaline phosphatase (ALP) and 2,4-dichlorophenoxyacetic acid (2,4-D). [email protected] @bCDs with well-resolved dual emissions is facilely synthesized by covalent conjugation of red-emissive quantum dots (rQDs), the internal standard, with blue-emissive carbon dots (bCDs), the Fe 3+ -specific fluorescent indicator . 2,4-D can specifically inhibit the enzymatic activity of ALP, leading to suppress the production of AA which can reduce Fe 3+ to Fe 2+ and thereafter trigger the fluorescence response of [email protected] @bCDs. Taking advantages of these highly specific cascade catalytic reactions , ratiometric fluorescence schemes are established for sensing Fe 3+ , AA, ALP and 2,4-D both in aqueous solution and on paper-based microarray . The smartphone-based fluorescence detector integrated with the [email protected] @bCDs-based microarray demonstrated good sensing performance with a wide linear range and low detection limit, and is successfully applied to quantitate 2,4-D in cabbage and tap water samples. The reported method which enables point-of-need quantitation in a sample-in-result-out manner and highlights its features of cost-effectiveness and ease-of-use, is ideally for food safety inspection, environment surveillance, health monitoring at point-of-need, especially in low resource settings.
研究领域:
分析化学
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环境科学
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食品安全
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生物技术
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产品关联
DOI
高影响因子
iScience
·
2023
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IF 5.8
Meng Xiao,Ningxia Xu,Aitong He,Zipei Yu,Bo Chen,Baohui Jin,Lelun Jiang,Changqing Yi
Summary Cost-effective and user-friendly quantitation at points-of-need plays an important role in food safety inspection, environmental monitoring, and biomedical analysis. This study reports a stand-alone smartphone-based fluorospectrophotometer (the SBS) installed with a custom-designed application (the SBS-App) for on-site quantitation of pesticide using a ratiometric sensing scheme. The SBS can collect fluorescence emission spectra in the wavelength range of 380-760 nm within 5 s. A ratiometric fluorescence probe is facilely prepared by directly mixing the blue-emissive carbon nanodots (the Fe 3+ -specific fluorometric indicator) and red-emissive quantum dots (the internal standard) at a ratio of 11.6 (w/w). Based on the acetylcholinesterase/choline oxidase dual enzyme-mediated cascade catalytic reactions of Fe 2+ /Fe 3+ transformation, a ratiometric fluorescence sensing scheme is developed. The practicability of the SBS is validated by on-site quantitation of chlorpyrifos in apple and cabbage with a comparable accuracy to the GC-MS method, offering a scalable solution to establish a cost-effective surveillance system for pesticide pollution.
研究领域:
分析化学
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环境科学
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食品安全
·
生物医学工程
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产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）