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A new fluorescent quenching method for the determination of phosphoproteins by using calconcarboxylic acid 下载免费PDF全文
Zhongxin Zhu Xinliang Zhu Jiayi Shen Ayi Zhou Maowei Ni Litai Jin Weitao Cong 《Electrophoresis》2015,36(6):924-929
A fluorescent quenching detection method for phosphoproteins in SDS‐PAGE by using calconcarboxylic acid (CCA) was described. In this method, the fluorescence intensity of CCA was greatly increased with the presence of Al3+ in the gel background, while in zones where phosphoproteins are located this intensity was absent because of fluorescence quenching phenomenon through the formation of CCA‐Al3+‐phosphoprotein appended complex. Approximately 4–8 ng of phosphoproteins can be selectively detected within 1 h (1D SDS‐PAGE), which is similar to that of the most commonly used Pro‐Q Diamond stain. The specificity of this novel technique for phosphoproteins was confirmed by dephosphorylation, Western blot, and LC‐MS/MS analysis, respectively. Furthermore, to better understand the newly developed method, the detection mechanism of CCA stain was explored by fluorescent spectrometry. According to the results, it is believed that CCA stain may provide a new choice for selective, economical, MS compatible, and convenient visualization of gel‐separated phosphoproteins. 相似文献
13.
Jet quenching has successfully served as a hard probe to study the properties of Quark-Gluon Plasma (QGP). As a multi-particle system, jets require time to develop from a highly virtual parton to a group of partons close to mass shells. In this study, we present a systematical analysis on the effects of this formation time on jet quenching in relativistic nuclear collisions. Jets from initial hard scatterings were simulated with Pythia, and their interactions with QGP were described using a Linear Boltzmann Transport (LBT) model that incorporates both elastic and inelastic scatterings between jet partons and the thermal medium. Three different estimations of the jet formation time were implemented and compared, including instantaneous formation, formation from single splitting, and formation from sequential splittings, before which no jet-medium interaction was assumed. We found that deferring the jet-medium interaction with a longer formation time not only affects the overall magnitude of the nuclear modification factor of jets but also its dependence on the jet transverse momentum. 相似文献
14.
Dr. Shanyu Han Prof. Antonio G. S. de Oliveira-Filho Dr. Yinan Shu Prof. Donald G. Truhlar Prof. Hua Guo 《Chemphyschem》2022,23(8):e202200039
We present a new full-dimensional diabatic potential energy matrix (DPEM) for electronically nonadiabatic collisions of OH(A 2Σ+) with H2, and we calculate the probabilities of electronically adiabatic inelastic collisions, nonreactive quenching, and reactive quenching to form H2O+H. The DPEM was fitted using a many-body expansion with permutationally invariant polynomials in bond-order functions to represent the many-body part. The dynamics calculations were carried out with the fewest-switches with time uncertainty and stochastic decoherence (FSTU/SD) semiclassical trajectory method. We present results both for head-on collisions (impact parameter b equal to zero) and for a full range of impact parameters. The results are compared to experiment and to earlier FSTU/SD and quantum dynamics calculations with a previously published DPEM. The various theoretical results all agree that nonreactive quenching dominates reactive quenching, but there are quantitative differences between the two DPEMs and between the b=0 results and the all-b results, especially for the probability of reactive quenching. 相似文献
15.
以脯氨酸(Pro)为保护剂,盐酸羟胺为还原剂,通过一步化学还原法制备脯氨酸稳定的铜纳米团簇(Cu NCs)。采用分子荧光仪和紫外可见吸收仪对Cu NCs的光学性质进行分析,通过透射电子显微镜(TEM)、X射线光电子能谱(XPS)和傅里叶变换红外波谱仪(FTIR)对Cu NCs的结构进行表征。TEM图像显示Cu NCs的形貌为球状,平均直径为1.89 nm。Cu NCs溶液在紫外光下呈蓝色,最大激发和发射波长分别为397和458 nm。Cu NCs的荧光可以选择性地被三硝基苯酚(PA)猝灭。该探针对PA的线性响应范围为0.5~15μmol/L和20~70μmol/L,检测限为0.092μmol/L(S/N=3)。可能的检测机理是静态猝灭和内滤效应。此外,该荧光探针已成功应用于实际水样品中PA的测定。 相似文献
16.
采用高温固相法成功制备了Na3Sc2-x-y(PO4)3∶xTm3+,yDy3+荧光粉,利用X射线衍射仪、扫描电子显微镜和荧光光谱仪对荧光粉进行了物相、形貌和发光性能进行了表征。 在Na3Sc2(PO4)3∶0.06Tm3+,yDy3+荧光粉中,物质的量分数6%的Tm3+和6%的Dy3+在360 nm激发下呈现出白光发射,其发射光谱在460~685 nm范围内存在Tm3+位于457 nm的特征发射峰,对应于Tm3+的3H6→1D2跃迁,以及Dy3+位于483、577和672 nm处的3个特征发射峰,分别对应于Dy3+的4F9/2→6H15/2、4F9/2→6H13/2和4F9/2→6H11/2的跃迁。 观测到Na3Sc2(PO4)3∶Tm3+荧光粉的发射光谱与Na3Sc2(PO4)3∶Dy3+的激发光谱有较好的重叠,且Tm3+的荧光寿命随Dy3+浓度的增加逐渐降低,因此在Na3Sc2(PO4)3∶Tm3+,Dy3+荧光粉中存在Tm3+向Dy3+的能量传递。 利用Dexter和Reisfeld近似分析了能量转移机制,发现从Tm3+到Dy3+的能量传递临界距离为1.6 nm,能量传递过程是通过偶极-偶极相互作用进行的。 Na3Sc2(PO4)3∶0.06Tm3+,0.06Dy3+荧光粉具有较好的耐受热猝灭性能,在423、473和523 K时的发射强度分别为298 K时发射强度的97.6%、89.2%和78.6%。 随着Dy3+浓度的增加,Na3Sc2(PO4)3∶0.06Tm3+,yDy3+荧光粉的发光颜色由蓝色转变为白色,再由白色变黄色。 Na3Sc2(PO4)3∶Tm3+,Dy3+荧光粉作为一种可调色或单相白光荧光粉在发光二极管上具有潜在的应用前景。 相似文献
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以氧化铕(Eu_2O_3)、甲基丙烯酸(MAA)、水杨酸(HSal)、肉桂酸(HCA)和菲咯啉(Phen)为原料制备了Eu(MAA)3Phen、Eu(Sal)_3Phen和Eu(CA)_3Phen探针分子,并将不同探针分子分别加到甲基丙烯酸甲酯(MMA)中,在过氧化苯甲酰(BPO)引发下聚合,制得一系列温敏漆样品。采用红外光谱仪、荧光光谱仪和扫描电子显微镜对探针分子的结构、发光性能、形貌和温敏漆的温度猝灭性能进行了表征,研究了不同配体对探针分子发光性能和温敏漆温度猝灭性能的影响。结果表明,探针分子Eu(MAA)3Phen的荧光强度明显高于Eu(Sal)_3Phen和Eu(CA)_3Phen,相应的3种温敏漆Eu(MAA)3Phen/PMMA、Eu(CA)_3Phen/PMMA和Eu(Sal)_3Phen/PMMA均有良好的温度猝灭特性,但是对比发现在55~65℃范围内Eu(MAA)3Phen/PMMA和Eu(CA)_3Phen/PMMA温敏漆的灵敏度较高,而在35~45℃范围内Eu(Sal)_3Phen/PMMA温敏漆的灵敏度较高,可见不同的温敏漆适用于不同的温度范围。 相似文献
19.
合成了5种m-6-m型Gemini双季铵盐表面活性剂,在对产物结构和表面活性进行分析的基础上,分别采用紫外分光光度法和荧光分光光度法考察了m-6-m型Gemini双季铵盐表面活性剂与DNA的相互作用.结果表明,m-6-m型Gemini表面活性剂的CMC随烷基疏水链的增长呈逐渐下降趋势.几种表面活性剂均没有使DNA的紫外吸收峰发生红移或蓝移现象,说明复合物无嵌插作用或氢键形成,表面活性剂与DNA作用后的吸光度随表面活性剂浓度的增大而增强,当表面活性剂的浓度相同时,吸光度随疏水链的增大而逐渐减弱.Gemini表面活性剂浓度增大导致荧光强度降低,表面活性剂与DNA作用时的猝灭为静态猝灭,随着疏水链长度的增长,荧光猝灭常数降低,表面活性剂与DNA之间的作用力减弱. 相似文献
20.
Animesh Roy Maximilian A. Silvestri Robert A. Hall Salvatore D. Lepore 《Tetrahedron letters》2017,58(1):106-108
In the attempt to synthesize substituted allenyl esters through a metathesis coupling of unsubstituted allenyl esters and alkenes using a variety of ruthenium catalysts, it was discovered that allenyl esters themselves cleanly arrested the activity of the catalysts. Further studies suggests possible utility of allene esters as general quenching agents for metathesis reactions. To explore this idea, several representative olefin metathesis reactions, including ring closing, were successfully terminated by the addition of simple allenyl esters for more convenient purification. 相似文献