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An insight into the in vivo imaging potential of curcumin analogues as fluorescence probes

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Asian Journal of Pharmaceutical Sciences 2021年第4期16卷 419-431页

作者： Yu Liu Chuang Zhang Hao Pan Li Li Yanjie Yu Bingmi Liu School of Pharmaceutical Sciences Liaoning UniversityShenyang 110036China Judicial Identification Center of Liaoning university Shenyang 110036China Liaoning Key Laboratory of New Drug Research&Development Shenyang 110036China Liaoning Pharmaceutical Engineering Research Center for Natural Medicine Shenyang 110036China

Curcumin and its derivatives have good electrical and optical properties due to the highly symmetric structure of delocalized π electrons. Apart from that, curcumin and its derivatives can interact with numerous molecular targets, thereby exerting less side effects on human body. The fluorescence emission wavelength and fluorescence intensity of curcumin can be enhanced by modifying its π-conjugated system and β-diketone structure. Some curcumin-based fluorescent probes have been utilized to detect soluble/insoluble amyloid-β protein, intracranial reactive oxygen species, cysteine, cancer cells, etc. Based on the binding characteristics of curcumin-based fluorescent probes with various target molecules, the factors affecting the fluorescence intensity and emission wavelength of the probes are analyzed, in order to obtain a curcumin probe with higher sensitivity and selectivity. Such an approach will be greatly applicable to in vivo fluorescence imaging.

关键词： Curcumin Fluorescent probe fluorescence characteristics Structural feature

Dissolved organic carbon fractionation in wet deposition and its potential impact on radiative forcing in the central Tibetan Plateau

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Research in Cold and Arid Regions 2023年第4期15卷 171-178页

作者： ZhaoFu Hu ChaoLiu Li ShiChang Kang XiaoFei Li Chao Zhang Fangping Yan XiaoBo He PengFei Chen State Key Laboratory of Cryospheric Science Northwest Institute of Eco-environment and ResourcesChinese Academy of SciencesLanzhouGansu 730000China School of Environmental Science and Engineering Shaanxi University of Science and TechnologyXi'anShaanxi 710021China University of Chinese Academy of Sciences Beijing 100049China

As an important component of carbonaceous matters,dissolved organic carbon(DOC)can absorb and scatter the solar radiation at ultraviolet and blue *** wet deposition process has great impact on the con-centration and light absorption ability of precipitation DOC,affecting the climatic effect caused by DOC in the *** this study,light absorption and fluorescence characteristics of precipitation DOC was investigated in the central Tibetan Plateau(TP).The results showed that the mean DOC concentration and mass absorption cross-section measured at 365 nm(MAC_(365)) in Tanggula(TGL)station were 0.59±0.42 mg/L and 0.37±0.19 m^(2)/g,respectively,while both values showed much higher volatilities than those of *** concentrations had significant negative correlation with the precipitation amount,while MAC_(365) values increase with the precipitation amount in TGL ***,DOC with high light-absorbing ability was preferred to be retained in the atmosphere during wet *** this study,precipitation DOC contained three fluorescent components(one humic-like component and two tyrosine-like components)mainly from local biomass burning *** concentration showed a negative relationship with MAC_(365) value in TGL *** wet deposition of DOC with low light-absorbing ability can reduce the strong negative radiative forcing caused by secondary organic aerosol due to high proportion of DOC in secondary organic *** phenomenon was also found in Nam Co,Lulang and Everest stations of previous study,which may have a potential impact on radiative forcing in the atmosphere of TP.

关键词： Tibetan Plateau Wet deposition Dissolved organic carbon Light absorption ability fluorescence characteristics

Chlorophyll fluorescence and Membrane Lipid Peroxidation in the Flag Leaves of Different High Yield Rice Variety at Late Stage of Development Under Natural Condition

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Acta Botanica Sinica 2002年第4期44卷 413-421页

作者：李霞焦德茂刘友良黄雪清南京农业大学农学院南京210095 江苏省农业科学院农业生物遗传生理研究所南京210014

With indica ( Oryza sativa L.) hybrid Shanyou 63 as control, the hybrid rice varieties including Peiai 64S/E32, Peiai 64S/9311, X07S/Zihui 100, Guangyou 881 and japonica 9516 were used to study changes of chlorophyll content, photosynthetic response to light intensity and temperature, chlorophyll fluorescence characteristics and membrane lipid peroxidation in their flag leaves at the late stage of development under natural conditions in Nanjing. The results were as follows:. primary photochemical efficiency of PS II ( F-v / F-m), quantum yield of linear electron transport of PS II (phi(PSII)), electron transfer rate (ETR) in these rice varieties decreased with their decrease of chlorophyll content during this period. This kind of impediment to energy conversion induced the transfer of excessive energy to the reducing side of PS I, hence the accumulation of O-2(radical anion) and peroxidation of membrane lipid, and resulting in the accumulation of malondialdehyde (MDA), that is the destroys of photosynthetic pigments and membranes and the consequent, premature senescence. This phenomenon is variable conspicuously in different rice varieties. Under natural condition in Nanjing, F-v/F-m, phi(PSII), ETR and quenching coefficient ( qP) in japonica 9516 tolerant to photooxidation decreased less and the conversion capacity of light energy was stable, premature senescence was unlikely, and consequently the seed-setting rate was higher. While F-v/F-m, phi(PSII), ETR and photochemical qP in Shanyou 63 sensitive to photooxidation decreased more and therefore premature senescence was easy to happen, thus the seed-setting rate and yield were all reduced. The tolerance to photooxidation and premature senescence in other hybrids derived from typical two line or three line crossing laid in the middle. From the rice breeding for super-high-yield, on the basis of the good plant-type of current rice, considering both hybrid vigor and the prevention premature senescence, it would be a

关键词： premature senescence photooxidation fluorescence characteristics lipid peroxidation rice

Spectroscopic characteristics of two typical soil humic acids in China

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Journal of Environmental Science and Engineering 2007年第1期1卷 29-38页

作者： ZHONG Tong-sheng YIN Zhi-fang LONG Li-ping HUANG Sha-sheng LI Fa-sheng State Key Laboratory of Chemo/Biosensing and Chemometrics College of Chemistry and Chemical Engineering Hunan University Changsha 410082 China . Department of Chemical ＆ Environmental Engineering Hunan City College Yiyang 413000 China College of Life and Environmental Science Shanghai Normal University Shanghai 200234 China Department of Soil Pollution Control Chinese Research Academy of Environmental Sciences Beijing 100012 China

Humic acid （HA） is known to be a complex organic compound with varying structural and functional characteristics. In this study, three-dimensional excitation emission matrix fluorescence spectroscopy （3DEEM）, ultraviolet-visible （UV-Vis） and Fourier-transform infrared （FT-IR） were applied to study the fluorescence characteristics and structure of two typical soil HAs in China. The effects of concentration of HA, pH and ionic strength on the fluorescence behaviors were investigated. The results indicate that ionic strength over the range from 0 to 0.05mol L^-1 NaNO3 did not affect the 3DEEM of HA. The concentration of HA and pH of the test solution had obvious effects on the 3DEEM. When the concentration of soil HA was lower than 10mg L^-1, HA has only one obvious fluorescence peak. However, there were several fluorescence peaks for HA in high concentration （≥50mg L^-1）, and its Ex/Em maximum wavelength shifted towards longer wavelength with increasing the concentration of HA. The fluorescence intensity of HA enhanced with the increase of pH, and achieved maximum at pH 10. The effect of pH on the fluorescence intensity of black soil HA （BHA） was the severest and a polycondensation of BHA existed with the change of pH. At the same condition, the fluorescence intensity of red soil HA （RHA） was stronger than that of BHA. At the excitation wavelength of 340nm, the maximum emission peak positions of RHA and BHA were 474 and 504nm at pH 6.0, and their fluorescence quantum yields （QY） were 2.1-2.5% and 1.5-1.9%, respectively. Based on the maximum emission peak positions and fluorescence quantum yield, RHA and BHA can be distinguished.

关键词： black soil humic acid red soil humic acid 3DEEM fluorescence characteristics