Determination of trace glucose and forecast of human diseases by affinity adsorption solid substrate-room temperature phosphorimetry based on triticum vulgaris lectin labeled with dendrimers-porphyrin dual luminescence molecule

In this paper, 3.5-generation polyamidoamine dendrimers (3.5G-D)-porphyrin (P) dual luminescence molecule (3.5G-D-P) was developed as a new phosphorescence-labeling reagent. Meanwhile, the room temperature phosphorescence (RTP) characteristics of 3.5G-D-P and its product of labeling triticum vulgaris lectin (WGA) on the surface of polyamide membrane (PAM) were studied. Results showed that in the presence of heavy atom perturber LiAc, 3.5G-D and P of 3.5G-D-P molecule could emit strong and stable RTP on the PAM. And the Tween-80 would spike thoroughly the phosphorescence signal of 3.5G-D and P; moreover, specific affinity absorption (AA) reaction between the products (Tween-80-3.5G-D-P-WGA) of WGA labeled with Tween-80-3.5G-D-P and glucose (G) was carried out. The products of the AA reaction could keep good RTP characteristics of 3.5G-D and P dual luminescence molecule, and the DeltaI(p) was linear correlation to the content of G. According to the facts above, a new method of affinity adsorption solid substrate-room temperature phosphorimetry (AA-SS-RTP) for the determination of trace G was established, basing on WGA labeled with Tween-80-3.5G-D-P dual luminescence molecule. The detection limit of this method was 0.13fgspot(-1) (1.7x10(-12)moll(-1), 3.5G-D) and 0.14fgspot(-1) (2.2x10(-12)moll(-1), P). Determination of G in human serum using excitation/emission wavelength of either 3.5G-D or P, the result was coincided with enzyme-linked immunosorbent assay (ELISA). Not only the sensitivity and accuracy of this method were higher, but also the flexibility of AA-SS-RTP was obviously improved and the applicability was wider.     

Structures and relative stability of medium- and large-sized silicon clusters. VI. Fullerene cage motifs for low-lying clusters Si(39), Si(40), Si(50), Si(60), Si(70), and Si(80)

We performed a constrained search, combined with density-functional theory optimization, of low-energy geometric structures of silicon clusters Si(39), Si(40), Si(50), Si(60), Si(70), and Si(80). We used fullerene cages as structural motifs to construct initial configurations of endohedral fullerene structures. For Si(39), we examined six endohedral fullerene structures using all six homolog C(34) fullerene isomers as cage motifs. We found that the Si(39) constructed based on the C(34)(C(s):2) cage motif results in a new leading candidate for the lowest-energy structure whose energy is appreciably lower than that of the previously reported leading candidate obtained based on unbiased searches (combined with tight-binding optimization). The C(34)(C(s):2) cage motif also leads to a new candidate for the lowest-energy structure of Si(40) whose energy is notably lower than that of the previously reported leading candidate with outer cage homolog to the C(34)(C(1):1). Low-lying structures of larger silicon clusters Si(50) and Si(60) are also obtained on the basis of preconstructed endohedral fullerene structures. For Si(50), Si(60), and Si(80), the obtained low-energy structures are all notably lower in energy than the lowest-energy silicon structures obtained based on an unbiased search with the empirical Stillinger-Weber potential of silicon. Additionally, we found that the binding energy per atom (or cohesive energy) increases typically >10 meV with addition of every ten Si atoms. This result may be used as an empirical criterion (or the minimal requirement) to identify low-lying silicon clusters with size larger than Si(50).     

Crystallographic evidence of an unusual, pentagon-shaped folding pattern in a circular aromatic pentamer

Introduction of a continuous hydrogen-bonding network suppressed the conformational flexibility of an oligomeric backbone. Cyclization of a rigidified, suitably sized oligomer led to a circular aromatic pentamer. Its crystal structure determined by X-ray crystallography reveals a pseudo five-fold symmetric planarity in the solid state, which is quite unusual among all the previously described shape-persistent macrocycles and synthetic foldamers with biased conformations enforced by noncovalent forces.     

电感耦合等离子体原子发射光谱分析中不同电离电位元素基体效应的比较研究

选择不同电离电位的基体元素K、Na、La、Y和Mg,比较研究了它们对分析元素谱线强度的影响,其影响程度与谱线激发电位及基体元素电离电位有定量的相关关系。碱金属基体(K、Na)和非碱金属基体(La、Y和Mg)对分析元素检出限、背景强度及其相对标准偏差的影响显著不同,后者的记忆效应也大于前者。La的电离电位与Na相差不大。但其基体效应与Y相似,表明墓体效应与基体元素的化学性质有关。     

稀土配合物的时间分辨光谱分析法研究(Ⅰ)TFA-TOPO-农乳-100体系用于测定铕和钐

本文采用自己组装的时间分辨荧光光谱测定装置,研究了铕(钐)-三氟乙酰丙酮-三正辛基膦化氧(Eu(Sm)-TFA-TOPO)在非离子表面活性剂农乳-100存在下的光谱特性、荧光衰减动力学特性和发光机理。提出了能量传递机制和第二配体TOPO在荧光发射过程中的作用,制定出TFA-TOPO-农乳-100体系测定痕量铕和钐的时间分辨荧光光谱分析方法,用于测定高纯氧化钇中的痕量铕和钐,结果令人满意。     

激光诱导荧光光谱分析法研究 Ⅳ.钐-三氟乙酰丙酮-三正辛基膦化氧-浓乳-100的荧光特性研究及应用

采用激光诱导荧光光谱测定装置研究了Sm-三氟乙酰丙酮(TFA)-三正辛基膦化氧(TOPO)体系的激光诱导发光特性和发光机理。根据配合物体系中各组份的光谱特性和光谱能级,提出Sm-TFA-TOPO体系的能量传递机制。拟定了在农乳-100存在下,TFA-TOPO体系测定痕量钐的激光诱导荧光光谱分析新方法。不经分离,用于氧化钇和合成水样中痕量钐的测定,操作简便、快速,结果令人满意     

混合价聚十五钒酸盐[V_(15)O_(36)Cl](NH_4)_3Na_7·30H_2O的合成与晶体结构

以XRD法确定制得的标题晶体属空间群D_(3A)~3,a=13.111,c=11.130。结构由帕特逊-极小函数法结合差值法解出,经精修得一致性因子R_w=0.0344。晶胞中坐落在6m2特殊位置上的是包合1个Cl~-的聚十五钒酸根[V_(15)O_(36)Cl]~(10-),配合键价法确认这是四价钒占主导地位的一类特种混合价同多酸根。