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Acta Pharmaceutica Sinica B 2012年第3期2卷 294-299页

作者： Fei Yang Cuige Liu Yongju Wei College of Chemistry and Material Science Hebei Normal UniversityShijiazhuang 050024China

A novel fluorimetric method for determination of paeonol,an active component of Chinese herbal medicine,is proposed.The method is based on the reaction of paeonol with aluminum ion in pH 4.4 HAc-NaAc buffer to form a fluorescent Al(Ⅲ)-paeonol complex.The maximum excitation wavelength and emission wavelength of the complex were 296 nm and 455 nm,respectively.The fuorescence quantum yield of the complex was determined to be 0.053 at an excitation wavelength of 296 nm.A linear calibration curve covered the concentration range 0.017-1.2μg/mL.The method has been applied to the analysis of paeonol in medicinal crop Cynanchi Paniculati Radix(Xuchangqing),and the results demonstrated that this method can be used for quality evaluation of crude drug Xuchangqing.

关键词： fluorescence analysis Chinese herbal medicine Paeonol Al(Ⅲ)-paeonol complex Cynanchi Paniculati Radix(Xuchangqing) 3D fluorescence spectrum

Ultraviolet humic-like component contributes to riverine dissolved organic matter biodegradation

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Journal of Environmental Sciences 2023年第2期124卷 165-175页

作者： Maofei Ni Siyue Li College of Eco-Environmental Engineering Guizhou Minzu UniversityGuiyang 550025China Research Center for Environmental Ecology and Engineering School of Environmental Ecology and Biological EngineeringWuhan Institute of TechnologyWuhan 430205China The karst environmental geological hazard prevention laboratory of Guizhou Minzu University Guiyang 550025China Key Laboratory of Reservoir Aquatic Environment Research Center for EcohydrologyChongqing Institute of Green and Intelligent TechnologyChinese Academy of SciencesChongqing 400714China

Biological degradation of dissolved organic matter(DOM)regulates its structure and fate in river ecosystems.Previous views suggested that labile components were dominantly consumed by microbial metabolism.Here we provide new observations that a part of recalcitrant compounds largely contribute to riverine DOM biodegradation.The excitationemission matrix fluorescent spectroscopy combined with peak picking and parallel factor analysis are used to explore component variability during DOM incubation.Humic-like and tryptophan-like DOM are the primary components of riverine DOM,with proportion contributions of 39%–82% and 16%–61% for % of the maximumfluorescence intensity,respectively.After 56 days of aerobic incubation in the dark,large amounts of tyrosine-like DOM generation are observed.Elevated temperature enhances the decomposition of ultraviolet humiclike substance and further stimulates labile DOM bio-mineralization into carbon dioxide.Meanwhile,averaged proportions of amino acid compositions(peak B and T)markedly increase(p<0.05)as the humic-like compositions(peak A,M and C)decrease after DOM incubation,suggesting incomplete degradation of refractory DOM from high-molecular to low-molecular weight compounds.The findings support the new notion of the continuous DOM biodegradation in a mode as“steps by steps”,contributing to a new understanding of carbon cycling for the UN Sustainable Development Goal.

关键词： Dissolved organic matter(DOM) Sequential biodegradation Recalcitrant compounds Component and fate fluorescence analysis

Dual Rolling Circle Amplification- Assisted Single-Particle fluorescence Profiling of Exosome Heterogeneity for Discriminating Lung Adenocarcinoma from Pulmonary Nodules

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CCS Chemistry 2023年第4期5卷 947-957页

作者： Yan Zhou Haoxiang Li Min Hou Jianjun He Jian-Hui Jiang Hunan Key Laboratory of Organ Fibrosis Department of Pulmonary and Critical Care MedicineThe Third Xiangya HospitalCentral South UniversityChangsha 410013 State Key Laboratory of Chemo/BioSensing and Chemometrics College of Biomedical SciencesCollege of Chemistry and Chemical EngineeringHunan UniversityChangsha 410082

Exosomes secreted by tumor cells carry abundant molecular biomarkers that reflect the status of their originating cells.These tumor-derived exosomes(TDEs)have emerged as attractive diagnostic targets.However,the identification and characterization of highly heterogeneous TDEs remain practically challenging.Here,we report a dual rolling circle amplification(DRCA)-assisted approach for the selective encapsulation of single TDEs for fluorescence microscopic and flow cytometric analysis.TDEs have been targeted by aptamers that recognized their surface tumor marker and exosomal marker CD63,following DRCA that produced entangling polymeric DNA chains,resulting in facile particle enlargement that allows single-particle fluorescence profiling of exosome heterogeneity.We have demonstrated the use of a dual-marker positive ratio for exosome differentiation and applied division and multiplication operations for normalized andmagnified marker heterogeneity analysis.We further applied this assay to distinguish lung adenocarcinoma and pulmonary nodule patients and found an accuracy of 90%.We anticipate promising transformations of this straightforward assay into clinically implantable diagnostic methods.

关键词： rolling circle amplification exosomes single-particle fluorescence analysis cancer diagnosis

Effects of PEG Molecular Weight on Its Interaction with Albumin

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Chinese Journal of Polymer Science 2015年第10期33卷 1373-1379页

作者： Jing-jing Lai Huai-yu Yan Yan Liu 黄延宾 Key Laboratory of Advanced Materials(MOE) Department of Chemical Engineering Tsinghua University

The fluorescence property of bovine serum albumin was investigated in the presence of PEGs of different molecular weights. Based on our results, we propose that PEGs of different molecular weights bind to albumin in the pH 7.4 aqueous solution, but only when the polymer size is larger than the protein size, one polymer chain may bind to multiple proteins and cause the proteins to aggregate.

关键词： Polyethylene glycol Bovine serum albumin Protein-polymer interactions fluorescence analysis

An examination of handwritten signatures forged using photosensitive signature stamp

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Forensic Sciences Research 2021年第2期6卷 168-182页

作者： Zhen Li Xinlai Liu Department of Documents examination criminal investigation Police University of chinashenyangChina

Signature examination is the most common examination performed by any document examiner.Determination of the authenticity of a handwritten signature on a questioned document is an important task for forensic document examiners in the forensic science field.As a result of continuous developments in technology,a signature stamp can now be created using a photosensitive seal to enable the reproduction of a handwritten signature.These stamps are commonly used in China and several other countries.In this study,10 types of black photosensitive stamp-pad ink,10 brands of fountain pen ink,15 types of black gel ink and six types of black erasable gel ink found on the Chinese domestic market were collected and 10 photosensitive signature stamps were created using the signatures of 10 people.Microscopic analysis,infrared(IR)and fluorescence analyses and microspectrophotometry(MSP)techniques were used to examine the resulting photosensitive signature stamp impressions when applied to printing papers,writing papers and invoice papers.By comparing the printing and spectral characteristics of the photosensitive signature stamp impressions with those of the signatures executed using the fountain pens,gel pens and erasable gel pens,it was possible to determine whether each signature was written or stamped using a photosensitive signature stamp.To validate these results,a 96.7%absolute accuracy and a 99.3%detection rate were achieved over a total of 150 blind tests conducted by five forensic document examiners,thus demonstrating that a combination of the four analysis methods used in this work can provide a more scientific approach and improve the accuracy and the detection rate of the examination process.

关键词： Forensic sciences questioned document forensic document examination signature examination photosensitive stamp microspectrophotometry IR analysis fluorescence analysis

AN APPROACH TO CUTTINGS FLUOROLOGGING USING HEXANE AS A SUBSTITUTE

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石油勘探与开发 1997年第4期24卷 92-96页

作者： Zhao Juying(Research Institute of Petroleum Exploration and Devempment, CNPC, Beijing, 100083)

It is discovered that carbon tetrachloride is a fluorescence quencher in crude oil detedion with cottings fluorologging. Hexane, which has many advantages as a substitute for carbon tetrachloride, is proposed. In this paper, four typical comparison results of fluorescence spectra of crude oil samples and some of field cores and cuttings are illustrated.The sensitivity of fluorescence analysis is increased by 10 to 35 times when we substitute hexane for carbon tetrachloride as the solvent of crude oil. We also find that the lighter the crude oil,the more Obvious the increase in analysis sensitivity. lt challenges the old concopt that coal-derived oil, condensate and some light oils do not emit fluorescence. The merit of hexane system in eliminating or reducing the fluorescent interference of modified asphalts in drilling fluids for cuttings fluorologging has also been discussed.

关键词： Cuttings logging fluorescence analysis Hexane Carbon tetrachloride Crude oil (fluorescence quench)

Monitoring of Heart Ischemia in Blood Serum

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Spectral analysis Review 2016年第2期4卷 11-22页

作者： Vladimíra Tomečková Vladimír Komanický Mohammad Kakoush Kristína Krajčíková Gabriela Glinská Monika Široká Lýdia Pundová Tomáš Samuely Dominika Hložná Dmytro Lotnyk Department of Medical and Clinical Biochemistry Faculty of Medicine Pavol Jozef Safárik University in Kosice Slovak Republic Institute of Physics Faculty of Science Pavol Jozef Safárik University in Kosice Slovak Republic 1st Department of Internal Medicine Faculty of Medicine Pavol Jozef Safárik University in Kosice Slovak Republic

Our aim was to study the selected cases of the patients with ischemic heart disease and to analyze the structure of blood serum of patients in comparison with control serum of healthy subjects by methods: synchronous fluorescence fingerprint and atomic force microscopy that are still not used in clinical practice. Our results of fluorescence analysis showed that blood serum of all patients with ischemic heart disease decreased intensity of fluorescence in comparison with control blood serum. Endogenous fluorescence of synchronous fluorescence fingerprint of blood serum of patients with unstable angina pectoris state after non ST elevation myocardial infarction;angina pectoris and arterial hypertension 3 was similar, but atomic force microscopy revealed differences in the structure of blood serum of patients with the angina pectoris. Blood serum of patients with angina pectoris exhibited disappearance of fluorescence peak with maximum fluorescence and showed lower fluorescence intensity than control blood serum and blood serum of patients with arterial hypertension 2. Profiles of synchronous fluorescence fingerprint of blood serum of patients with arterial hypertension stage 2 showed formation of the new fluorescent peak with maximum fluorescence, similar shape of synchronous fluorescence fingerprint and higher fluorescence intensity than blood serum of healthy subjects. Blood serum sensitively revealed changes in the body by using untraditional novel techniques which enable the analysis of the mixture of blood serum and might be a new possibility in study of heart ischemia diseases.

关键词： Blood Serum fluorescence analysis Atomic Force Microscopy Ischemic Heart Disease

Design and Quantitative analysis of Fluorescent Immunoassay Detection System

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Design and Quantitative Analysis of Fluorescent Immunoassay ...