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Pyrrole and Pyrimidine Derivatives as Possible Electron Donors for Colored Charge-Transfer Complexes with a Weakly Electrophilic Energetic Material,FOX-7:A Theoretical Study

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火炸药学报 2023年第5期46卷 390-398,I0002-I0008页

作者： Sergey V.Bondarchuk Department of Chemistry and Nanomaterials Science Bogdan Khmelnitsky Cherkasy National Universityblvd.Shevchenko 8118031 CherkasyUkraine

A number of electron-rich heterocycles are studied as potential reagents for visual colorimetric detection of FOX-7 due to colored charge-transfer complexes formation.The obtained results suggest that pyrrole and pyrimidine derivatives can form such complexes playing the role of electron donors despite a low electrophilicity of FOX-7.Density functional theory calculations,as well as quantum theory of atoms in molecules analysis,suggest stacking binding mode as the most preferable one with the binding energy of about 21-36 kJ/mol.All the complexes demonstrate a clear single charge-transfer absorption band in the visible region and the expected colors of the complexes are varying from violet and blue to red and orange.The calculations of the crystalline state of the studied complexes indicate high lattice energies,which are higher than that of pure FOX-7 and are close to the recently reported hydrogen-bonded complex of FOX-7 with 1,10-phenanthroline.Additional analysis of the studied charge-transfer complexes using properties based on density difference grids clearly suggests the acceptor role of FOX-7 in the complexes.This analysis can be effectively applied to identify the nature of other possible complexes of FOX-7,in which its role is unclear because of the specific reactivity,namely,both weak electrophilic and nucleophilic properties at the same time.

关键词： FOX-7 charge-transfer colorimetric analysis detection of explosives quantum-chemical calculation

A cellphone-based colorimetric multi-channel sensor for water environmental monitoring

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Frontiers of Environmental Science & Engineering 2022年第12期16卷 67-78页

作者： Yunpeng Xing Boyuan Xue Yongshu Lin Xueqi Wu Fang Fang Peishi Qi Jinsong Guo Xiaohong Zhou State Key Laboratory of Urban Water Resource and Environment School of EnvironmentHarbin Institute of TechnologyHarbin150090China State Key Joint Laboratory of ESPC Center for Sensor Technology of Environment and HealthSchool of EnvironmentTsinghua UniversityBeijing100084China Key Laboratory of the Three Gorges Reservoir Region’s Eco-Environments of MOE Chongqing UniversityChongqing400030China

The development of colorimetric analysis technologies for the commercial cellphone platform has attracted great attention in environmental monitoring due to the low cost,high versatility,easy miniaturization,and widespread ownership of cellphones.This work demonstrates a cellphone-based colorimetric multi-channel sensor for quantifying multiple environmental contaminants simultaneously with high sensitivity and stability.To improve the sensitivity of the sensor,a delicate optical path system was created by using a diffraction grating to split six white beams transmitting through the multiple colored samples,which allows the cellphone CMOS camera to capture the diffracted light for image analysis.The proposed sensor is a universal colorimetric detection platform for a variety of environmental contaminants with the colorimetry assay in the range of 400–700 nm.By introducing the diffraction grating for splitting light,the sensitivity was improved by over six folds compared with a system that directly photographed transmitted light.As a successful proof-of-concept,the sensor was used to detect turbidity,orthophosphate,ammonia nitrogen and three heavy metals simultaneously with high sensitivity(turbidity:detection limit of 1.3 NTU,linear range of 5–400 NTU;ammonia nitrogen:0.014 mg/L,0.05–5 mg/L;orthophosphate:0.028 mg/L,0.1–10 mg/L;Cr(VI):0.0069 mg/L,0.01–0.5 mg/L;Fe:0.025 mg/L,0.1–2 mg/L;Zn:0.032 mg/L,0.05–2 mg/L)and reliability(relative standard deviations of six parallel measurements of 0.37%–1.60%and recoveries of 95.5%–106.0%in surface water).The miniature sensor demonstrated in-field sensing ability in environmental monitoring,which can be extended to point-of-care diagnosis and food safety control.

关键词： colorimetric analysis Multi-channel sensor Cellphone Water quality indexes Environmental monitoring

Improved analytical performance of smartphone-based colorimetric analysis using a power-free image box

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Improved analytical performance of smartphone-based colorime...

Identification of Arceuthobium globosum using unmanned aerial vehicle images in a high mountain forest of central Mexico

中国化学会第十三届全国分析化学年会

作者： Gang Chen Ling Yu Institute for Clean Energy ＆ Advanced Materials Faculty of Materials ＆ EnergySouthwest University

Smartphones-based colorimetric analysis systems are favoured for point-of-care testing applications. However, the image quality typically suffers from nonuniform and non-reproducible lighting, which negatively affects the accuracy of analyses. The present work proposed a power-free imaging box to utilize the light source of smartphone. The imaging box effectively eliminated interference arising from ambient light, while a V-shaped optical pipe coupled to the light source of smartphone was adopted to redirect the light to the sides of the box to eliminate the direct reflection of light from the surface of the target. This configuration was verified by numerical simulations. The specular reflection of the microfluidic chip was eliminated by establishing ideal diffuse light conditions. Moreover, the color images of a glucose testing on a paper strip and an enzyme-linked immunosorbent assay（ELISA） on transparent microchannels were captured with the proposed configuration, resulting a reduced assay variation and improved the lowest detection limit. The proposed imaging box improves the detection limit of colorimetric analysis, which highlights the potential of smartphone-based colorimetric analysis systems in point-of-care testing applications.

关键词： point-of-care testing smartphone-based imaging box chips colorimetric analysis

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Journal of Forestry Research 2020年第5期31卷 1759-1771页

作者： Luis A.Leon-Banuelos Angel R.Endara-Agramont William Gomez-Demetrio Carlos G.Martınez-Garcıa E.Gabino Nava-Bernal 50000 TolucaMexicoMexico

The identification of forests infested by parasitic plants is important for the design of appropriate control and prevention strategies.Satellite images and geographic information systems are commonly used to analyze the presence of pest and parasitic plants in the forests.However there is a need for finer resolution.In the last decade,the use of unmanned aerial vehicles has become increasingly common for capturing aerial images(colorimetric ranges for use in identification of Yellow Dwarf Mistletoe(YDM)(Arceuthobium globosum)in aerial images taken in a forest of central Mexico via a programmed algorithm.Three tonalities of YDM were classified according to its phenological stages,viz.green(young stage),yellow(adult stage),and brown(senescence stage),considering two light intensities,sunny and cloudy.Non-parametric tests were used in statistical analyses.The Spearman test showed significant negative correlation(p<0.001)between phenological stage and colour,indicating that lower RGB values were associated with greater age.The differences between groups were analysed using Kruskal–Wallis(p<0.01)and Mann–Whitney tests(p<0.01).The applied algorithm identified the presence and predominant colours of YDM according to its phenological stage.

关键词： colorimetric analysis RGB Pinus hartweggi Parasitic plants Remote sensing

Influence of Blueberry and Jaboticaba Agroindustrial Residue Particle Size on Color Change of Corn Starch Based Films Submitted to Different pH Values Solutions

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Journal of Renewable Materials 2019年第3期7卷 235-243页

作者： Cláudia Leites Luchese Julia Menegotto Frick Pavoni Jordana Corralo Spada Isabel Cristina Tessaro Laboratory of Packaging Technology and Membrane Development(LATEM) Department of Chemical Engineering-Federal University of Rio Grande do Sul(UFRGS)Street Ramiro Barcelos2777.Porto Alegre/RS-ZC:90035-007-Brazil

Corn starch,glycerol and agroindustrial residues were used to produce films by casting.By-products from juice processing,blueberry and jaboticaba in powder with different particle sizes were added in the filmogenic matrix to evaluate its potential as a colorimetric indicator.Blueberry and jaboticaba peels are commonly discarded although contain high amount of important compounds as anthocyanins.These compounds have the ability to color change after immersion in different pH values,demonstrating its potential for the intelligent packaging development.Analyses were performed in a colorimeter after films immersion in different buffer solutions.Visual color changes were perceived;reddish and bluish color in acidic and basic pH values,respectively.Independently of the particle size,theΔE* values were greater than 5,showing visually perceptible change to the human eye.The results indicate the potential of use of these residues as a pH indicator for the development of renewable and biodegradable sensor of food deterioration.

关键词： Blueberry jaboticaba anthocyanin casting colorimetric analysis

Pyrophosphate-Mediated On-Off-On Oxidase-Like Activity Switching of Nanosized MnFe_(2)O_(4) for Alkaline Phosphatase Sensing

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Journal of analysis and Testing 2019年第3期3卷 228-237页

作者： Xiangheng Niu Kun Ye Zhibo Li Hongli Zhao Linjie Wang Jianming Pan Hongwei Song Minbo Lan Institute of Green Chemistry and Chemical Technology School of Chemistry and Chemical EngineeringJiangsu UniversityZhenjiang 212013China Shanghai Key Laboratory of Functional Materials Chemistry School of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China School of Environmental and Chemical Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China

Developing reliable and facile approaches for alkaline phosphatase(ALP)sensing is important due to its role as a clinical biomarker for many diseases.In this study,we proposed a new and convenient colorimetric assay based on the pyrophosphate(PPi)-mediated oxidase-mimicking activity switching of nanosized MnFe_(2)O_(4) for the detection of ALP.The synthesized MnFe_(2)O_(4) exhibited high oxidase-like activity to catalyze the oxidation of colorless 3,3′,5,5′-tetramethylbenzidine(TMB)to its blue product TMBox in the presence of dissolved O2,leading to a color reaction rapidly and remarkably;PPi could significantly inhibit the activity of the MnFe_(2)O_(4) nanozyme via the strong interaction between PPi and the Fe(III)species in MnFe_(2)O_(4),resulting in the suppression of the TMB color reaction;when ALP was added,it hydrolyzed the PPi substrate to phosphate(Pi)that had no obvious effect on the MnFe_(2)O_(4) activity,and such that the TMB color reaction catalyzed by the nanozyme could be observed again.With the above principle,linear colorimetric determination of ALP in the scope of 0.6-55 U L−1 was achieved,giving the limit of detection down to 0.27 U L−1.Besides,the developed assay could provide selective response toward ALP against other co-existing biological species.Furthermore,reliable detection of ALP in human serum samples was verified by our assay,revealing its great promise as an effective and facile tool for ALP monitoring in clinical practice.

关键词： Oxidase-like nanozyme Activity switching PPi ALP colorimetric analysis

Novel Colorimetry-Based Android Smartphone Application for Detection of Ibuprofen

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Journal of Donghua University(English Edition) 2017年第3期34卷 362-366页

作者：平婧柳建设 State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry College of EnvironmentalScience and Engineering Donghua University Shanghai 201620 China

Sensitive and fast detection of ibuprofen( Ibu) in an aquatic environment often requires costly, time-consuming and sophisticated techniques. To tackle those limitations,a novel android smartphone application was developed based on a colorimetric analysis method using unmodified gold nanoparticles( AuNPs)aptamer probes to quantitatively detect Ibu. Under optimal conditions,it could detect Ibu as low as 0. 25 ng/mL with high selectivity. The determination of Ibu in real water samples was also carried out to confirm the practicability of the application.

关键词： android smartphone application colorimetric analysis ibuprofen(Ibu)